Wow, I just happened to come across this video and I found the explaination super helpful with such a complex concept (you can tell that I'm not a science major here). The use of interactive graphics really helps guide the viewers to have a better understanding of the talk. But the real genius is how Mr. Arnold breaks the concept down and use simple languages to clarify the complexities of space-time (I'm still not there yet but may be I will someday). STEM students can truly benefit from this type of education. I'll definitely keep following this and hope my granddaughter will benefit from this someday, should she chooses to go into science/engineering. Thank you.
My favorite concept which I read way back when I was in Junior High school is that "when you travel at any speed you trade space for time." You gain time (time dilation) and you lose space (length contraction).
Good explanation. In my opinion, space does not contract, but rather the travelling object simply viisits less places the faster it goes. If it had to visit all places between the start and end it would have to visit anifinite number of them (because you can always sub divide between two points), which would take forever. Zenos paradox about the movement of an arrow first highlighted the infinite number of points between any two places. Modern maths makes a pathetic attempt, by inventing the concept of limits (where the crux phrase is 'at infinity', which of course can't happen), to show movement is possible if you draw a line of ink on paper, the ink will not be contigous, and the faster you draw the line, the less places the ink will mark the paper. I think it's the same for spacetime. The faster you go, the less places iyou 'visit. It works the other way too. The faster you go the less points of time you vist, so it seems time contracts. Time dialation is (in my opinion) when points in time are skipped over just like the points in space. 🙂
@nswanberg not moving at all isn't the slowest you can go in space, correct? Extreme curvature of the space you're not moving in also plays a role in how "still" you are to outside observers. I propose you are more still relative to the rest of the universe while you are falling into a black hole, despite the presumption that falling is moving. It isn't in this case -- let me explain. When you swap space and time coordinates is when you're most still in my opinion, as falling towards and reaching the singularity is as inevitable as "falling" into the future in any given moment. So movement towards the singularity in a black hole isn't through 3 dimensional space, but through 1 dimensional time. The singularity IS your future, and there's no way to avoid it. You can move out of its way no more than you can move back in time. So I would say the singularity is the slowest you could move, but what do I know
@@RedNomster Good stuff! Also, the more still an object is it seems, the cooler it is. The cooler something is the less engery it has. So perhaps black holes are the coldest places in the unviverse, with the least energy? Just outside the event horizon then (too adhere to the conservation of energy), there should be all the engery of the particles that pass across it, and hence this would be very 'hot'?
I love that you casually gave one of the most intuitive explanations for the twin paradox as an aside for your main subject matter. Your talent and hard work as an educator is so incredibly rare. Thank you.
The video did not cover the twin paradox. It only showed what observer A would see about observer B time. It did not show what observer B would see of observer A time. So it did not show the paradox, that from observer A perspective B time is slower and from observer B perspective A time is slower.
@@Va1demar This is literally the very first thing covered by every single explanation of Special Relativity. Admittedly, some of the explanations suck, but to summarize... actually, I'm just going to go to bed, there are dozens of good videos about this on RUclips that you can watch, here, for free.
@@yziib3578 Both observers agree with each other about the spacetime interval each traveled. If one twin only travels on one side of the triangle, then the other twin *must* travel along the two other sides of the triangle. Spacetime intervals are invariant. Two sides of a triangle are always longer than the third side. Do the Twin (so-called) "Paradox" with triplets or quadruplets and it should make more sense.
@@Va1demar I struggle to understand your point from a theoretical perspective, but please bear in mind we have an incredibly large amount of empirical evidence for a constant speed of light. As in we go out and measure it under many many different scenarios and it comes out the same.
0:08: 🌌 The concept of space-time is essential for the existence of the universe and all physical phenomena. 2:54: 🌐 The concept of combining space and time into a 4-dimensional continuum called spacetime is not intuitive, but can be understood by comparing it to the geometry of space. 5:31: ⏳ Time and space have an inverse relationship, as shown by the equation E^2 = t^2 - x^2. 8:21: ⏳ The concept of time and its relationship with space explained, including the conversion between the two using the speed of light. 11:09: 🌌 The existence of 3 spatial dimensions and 1 temporal dimension is crucial for the existence of life and to avoid paradoxes. 13:53: 📚 Brilliant offers a practical course on Special Relativity with interactive learning tools and monthly new content. Recap by Tammy AI
The bigger question revolves around whether spacetime, the foundation of our current physics models, can still be considered the fundamental layer of reality, or if it instead originates from a more foundational underlying structure. While our current models have thrived on the spacetime framework, recent challenges and breakdowns in certain areas have prompted us to question whether spacetime alone can continue to provide a comprehensive explanation.
That's why so many physicists have spent their lives trying to formulate one equation for the entire universe. Einstein has been the closest with E=mc2. But that only says energy must have mass and vice versa. It doesn't account for time, which is relative to the observer. So easy to understand yet so hard to grasp until you grasp it.
I’m wondering if, and how, fields play into this structure? As he has demonstrated in other videos, space is made up of fields, like the Higgs field, and other boson fields. Is there any connection between these fields and the 4 dimensions that our universe appears to have? Matter cannot exist without these fields, so, can we have three dimensions without these fields? I’m not even sure I’m asking the right question.
@@alphagt62 > Is there any connection between these fields and the 4 dimensions that our universe appears to have? Yes, they're deeply connected. The fields that we describe in the Standard Model only work in 4 dimensions. (Of course you can create fields in other numbers of dimensions, but they would not be the fields of the Standard Model. They would be something completely different.) > Matter cannot exist without these fields Matter _as we know it._ That's a very important caveat to always keep in mind when we're discussing these kind of philosophical topics that we can't prove (or disprove) using any known science. > can we have three dimensions without these fields? Fields are a mathematical model we humans use to describe what we've learned about reality, but they don't define reality. Reality just is what it is. It existed long before we invented the concept of "fields" and it will continue to exist long after we and our knowledge of fields has gone extinct. > I’m not even sure I’m asking the right question You are, you're just asking it in the wrong frame of mind. You need to dissociate what the universe is from how we mere mortals understand the universe (and that's not particularly easy - don't feel bad about it!) One thing to always remember is that these questions cannot be answered (at least not without a view of the universe from outside the universe, which we're unlikely to ever get). They're philosophical questions rather than scientific, and they're questions philosophers have been struggling with for as long as humanity has existed. Each era within the framework of their own knowledge of course - the ancient Greeks for example pondered their "celestial spheres" rather than our current conceptualization of fields within the Standard Model - but the underlying questions are essentially the same. Anyway that's enough rambling from me. I'll say you're off to a good start! Happy philosophizing! :D
@@alphagt62so the fields actually are space time. The 3 physical dimensions are just those fields all stacked on one another and that forms the “fabric” of reality
Considering the longstanding emphasis on spacetime as the foundation of reality, it's worth pondering if we've got it reversed. What if consciousness is the true fundamental layer, from which spacetime and all its intricacies emerge? Challenges in our current models might be pointing us towards such a profound paradigm shift. There are many scientists now seriously considering this. Look up Prof. Donald Hoffman and his work on this.
Hello Arvin. You should be made the education minister for the whole world owing to your exceptional pedagogic skills. Schools in general tend to repress creative questions from children. Someone like you would reverse that and then we will not just be finding new answers, but we will also be finding new questions, both of which are paramount for scientific progress. Excellent video as always. I especially liked you putting a very obvious question 'how can two quantities with different dimensions be equated'. One question: In the video you mentioned that multi dimensional time would allow time loops to exist. How is it then that we humans are trying to invent a time machine in a space-time which has only one dimension for time? Shouldn't it be outrageously impossible?
One of the simplest best presentation of space time. For our future young generation scientist, it is very important to understand the space time concept. It is necessary to extend our understnding of Einstein's Theory of relativity, his EMC² and also the new concepts on Gravitation...is not a force and beyond. As usual, good job from ARVIN.
Well I guess that’s to say time is relative to the perspective of each person because it’s limited by the speed of light? So somebody in another galaxy is existing in our future, but at the same time from their perspective we are existing in their future…I need to watch the video again 🧐
It's because of inertia. Moving at a constant velocity is exactly the same as standing still. Everyone and everything is standing still with respect to itself, and so relative to itself, it emits light at the speed of light.
@@gaopinghu7332, High-energy muons decay slowly because they are not similar to the low-energy muons. It doesn't mean that speed changes the time. Also, photons experience time even if they don't decay faster, and their wavelenth increases with time. Planck time is not relative.
Great video! I find it helpful to think speed is converted from time. We are all moving through time at the speed of light. You hinted at the conversion factor… borrowing just a little time and can give you a lot of extra speed Gravity is constant acceleration so we need speed to overcome that and appear stationary. So we convert some of our time to speed so our time goes a little slower.
No constant speed can "overcome" non-zero acceleration, this part doesn't check out. To compensate for acceleration and appear stationary you need another acceleration, i.e. changing speed, but it would mean changing time dilation.
@ExistenceUniversity yes we are all traveling at the speed of light. Sorry, but you are wrong. Here is the proof: ruclips.net/video/au0QJYISe4c/видео.html From science clic English.
@@Name-js5uq Science clic is wrong. If you were traveling at the speed of light then you'd have no experience of time or space. You wouldn't exist as you do. In fact you can find my 2 year old debunking of his video in that comment section lol
Arvin, this was a wonderful presentation, made beautiful because of your faith. Your love of creation really came out and really makes this video special (not relatively, absolutely). After 23 seconds “space time, the canvas, that the Painter with all the colours needed to create their master piece” And at the end, the fine tuning, If the universe were any different, one dimension more one less, and we wouldn’t exist Finally, you gave thanks along with the loving couple gazing at the stars. You mentioned thanking your lucky stars- but I take this as code word for thanking something else that really does exist. God bless you.
On one hand, this is the closest I've ever come to grasping the concept, so bravo for Arvin. On the other hand, if C is distance/time, then C squared would be distance squared over time squared. Well, I know what a distance squared is (three inches on the sides of a square yields nine square inches), but I can't grasp the meaning of a time squared. What's a square second? This continues to flummox me. Still, it's the clearest demonstration of the concept I've seen so far, and my livelihood doesn't depend on my understanding it, so I'm satisfied for today.
Maybe this won't help you, but a squared second would be something we cannot intuitively understand, as we don't have the practical experience. Said otherwise, in the practical sense, it has no meaning. Like a meter to the fourth, we don't have the practical experience. What we can do is process it analytically, and maybe it's easier to figure out what a fourth dimension of space might be as we already deal with three of them. Other than that, a fourth dimension of space has no practical meaning. Another possible way of looking at it, although again it may not be helpful at all, is to consider acceleration. If velocity is the rate of change of distance per time unit (second) and acceleration is the rate of change of velocity per time unit, then acceleration would be the rate of change of distance per time unit squared (squared second). Or, maybe more properly said, the rate of change, per time unit, of the rate of change, per time unit, of the distance. The analytical meaning(?) here would be that we had to consider twice independent variations in time.
Good explanation. The acceleration example was what occurred to me as well: change in velocity per change in time or change in distance per second per second. Like the gravitational acceleration at MSL on earth, 9.8 m/s^2 for a free falling mass in a vacuum.
You are so smart. I’m an Electrical Engineering Technician and fully understand what time is now. Great Video and excellent special effects. 🤗 Subscribed ✔️
I think the oddest, weirdest, and most significant science discovery was by Maxwell. His differential equations showed the speed of light was constant to all observers. That's told us that the universe was one weird place.
@@APBT3chnoM0nkeyWHAT E=MC2 FUNDAMENTALLY means is that gravity/acceleration involves what is balanced inertia. INDEED, gravity AND ELECTROMAGNETISM/energy are linked AND BALANCED opposites; AS ELECTROMAGNETISM/energy is CLEARLY AND NECESSARILY proven to be gravity (ON/IN BALANCE). Consider TIME AND time dilation ON BALANCE. This CLEARLY proves what is the fourth dimension, AND this CLEARLY solves what is the coronal heating “problem”. I have proven why the rotation of WHAT IS THE MOON matches the revolution, AS I have proven why WHAT IS THE MOON will (and does) move away very, very, very slightly in relation to WHAT IS THE EARTH/ground !!!! By Frank Martin DiMeglio Gravity/acceleration involves what is balanced inertia, as WHAT IS E=MC2 is taken directly from F=ma; AS the rotation of WHAT IS THE MOON matches the revolution. This is CLEARLY consistent with the FOURTH dimension AND conservation of energy, AS the stars AND PLANETS are POINTS in the night sky. (INDEED, gravity AND ELECTROMAGNETISM are linked AND BALANCED opposites.) Consider what is THE EYE ON BALANCE. What is E=MC2 is consistent with TIME AND time dilation ON BALANCE, AS ELECTROMAGNETISM/energy is CLEARLY AND NECESSARILY proven to be gravity (ON/IN BALANCE); AS TIME is NECESSARILY possible/potential AND actual ON/IN BALANCE; AS E=MC2 is taken directly from F=ma; AS the stars AND PLANETS are POINTS in the night sky ON BALANCE; AS c squared CLEARLY does represent a dimension of SPACE (ON BALANCE); AS the rotation of WHAT IS THE MOON matches the revolution. Great. MOREOVER, WHAT IS THE MOON will (and does) move away very, very, very slightly IN RELATION TO what is THE EARTH/ground. Great. I have FUNDAMENTALLY and truly explained the cosmological redshift AND WHAT IS THE FOURTH dimension. (Consider WHAT IS complete combustion AND WHAT IS E=MC2.) GREAT. Again, gravity/acceleration involves what is balanced inertia; AS WHAT IS E=MC2 is taken directly from F=ma; AS I have FUNDAMENTALLY and truly explained the motion of what is THE MOON; AS ELECTROMAGNETISM/energy is CLEARLY (AND NECESSARILY) proven to be gravity (ON/IN BALANCE). Great !!!! Again, consider TIME AND time dilation ON BALANCE. Perfect. Think. Again, I have CLEARLY proven WHAT IS the FOURTH dimension ON BALANCE. “Mass”/ENERGY is CLEARLY electromagnetic/gravitational ON/IN BALANCE. GREAT !!!! By Frank Martin DiMeglio
The beauty of Arvin Ash's video is that after watching it for just a few minutes, I immerse myself in the experience, likening myself to a subatomic particle, and attempt to truly grasp what Arvin is conveying, and that's why it takes a couple of hours to watch the full video.
The explanations in this video as to why there are exactly 3 spatial dimensions and one time dimension in space/time seems to provide an argument against string theory, which requires either 11 or 26 spatial dimensions depending on symmetry considerations.
String theory theorizes dimensions that are small and curled up inside the large 3 spatial dimensions. Such dimensions could exist, but 4 or more large spatial dimensions are essentially ruled out.
If these small “extra” dimensions are curled up to smaller than the Planck length, can we ever perceive them, or are they just a mathematical construct (convenience) to allow string theory to “work”?
Scientists now believe that empty space is actually filled with Quantum or Vacuum Fluctuations. _"Vacuum fluctuations appear as virtual (i.e. non-material) particles, which are always created in particle-antiparticle pairs. Since they are created spontaneously without a source of energy, vacuum fluctuations and virtual particles are said to violate the conservation of energy. This is theoretically allowable because the particles annihilate each other within a time limit determined by the uncertainty principle so _*_they are not directly observable._*_ "_ (Source: Wikipedia) Despite its name, Virtual “Particles" are *immaterial.*
Wow! Brilliant thanks. Been looking to get the Minkowski graph explained in the sense of shortest/longest distance concept and the C indicator in the vertical time coordinate. Your graphs are excellent as are your explanations. Hard to find teacherswho can word these kind ocomplexities properly.
I am no novice of the subject and I always click on videos that look like it could help me understand a bit more: this was a mistake as I am a little bit confused now. I have to go elsewhere to get some understanding back.
The key is understanding 4:40 and 6:40. In space, the *shortest* route is a straight line. In time, the *quickest* route is anything but a straight line, BECAUSE, moving slows down time relative to the traveler themself. It's only misleading if you're assuming slow velocities like walking (it's mathematically still true, just a negligible difference), or more apparently, that the traveler in greater motion meets the non-moving traveler at a later time. They both meet at the same exact time, but one took a longer path through space, and motion through space slows time for that person relative to a stationary observer. The closer you are to the speed of light, the slower time passes for you, relative to a stationary observer. Light itself experiences no time, because it travels at the fastest possible velocity in the universe. This is special relativity. General relativity on the other hand paints the opposite scenario, depicting the slowest possible velocity in the universe. When falling into a blackhole, the dimensions of time and space flip. Instead of 3 dimensions of space, there is only 1, because no matter how fast you're going in any "direction" you'll always end up falling into the singularity of the black hole. It is physically the only location in 3 dimensional space you can head towards, and there's nothing you can do to stop it, which is synonymous with 1 dimensional time. AKA, the future.
@@RedNomsterSo time is slower the closer you are to the speed of light - what if you’re moving away from each other at the speed of light, would time appear stopped from each person’s perspective when looking back at the other person? But then if you’re travelling towards each other at the speed of light you would collide at twice the speed of light, so speed is relative as well? And because you need light to see, it would be like someone killed you in your past?🧐😅
@@steveco1800 moving at light speed would require you to be massless. Like a photon (light), if you reach lightspeed, you wouldn't see anything, because you would have 0 time to experience during your travels. But, if you're traveling very near the speed of light, according to special relativity, you experience light like ever before. Meaning a person in a car traveling near the speed of light would actually see their headlights shine and illuminate what's in front of them like ever before. Light is the same for all observers, stationary or not. It seems unintuitive, but it's experimentally proven! It would look different, though. As you're traveling near light speed, light coming in your direction, aka the universe and objects you see would be blue shifted. The same way cosmic expansion causes redshift by expanding the space and thereby light waves traveling in space, light waves from behind you would be redshifted. It's called the doppler affect, and is the same as sirens 🚨 sounding louder as they approach, but quieter after they pass you, even if they're the same distance from you at both moments. Faster than light speeds is when you start seeing yourself in the past and such! But that's a theoretically impossible velocity through space.
@@steveco1800It doesn't matter rather you're traveling toward, or away from something, or somebody in regards to how time passes. But it matters how much activity is spent within your travel in time.
It would interesting to understand the notion of spacetime from a LQG perspective or a quantized fields approach, for example the notion of "points in spacetime" would be replaced by what? Traditional Minkowsky spacetime would have any meaning at all in LQG? Or it would it be replaced by a spinfoam where the traditional notion of points in space would cease to have any meaning at all?
General relativity and quantum mechanics will never be combined until we realize that they take place at different moments in time. Because causality has a speed limit (c) every point in space where you observe it from will be the closest to the present moment. When we look out into the universe, we see the past which is made of particles (GR). When we try to look at smaller and smaller sizes and distances, we are actually looking closer and closer to the present moment (QM). The wave property of particles appears when we start looking into the future of that particle. It is a probability wave because the future is probabilistic. Wave function collapse happens when we bring a particle into the present/past. GR is making measurements in the predictable past. QM is trying to make measurements of the probabilistic future.
Whats stopping you using GR to make measurements of the probabilistic future?... Nothing, your statement is wrong. I feel like you're getting hung up on the time aspect when the forces involved are at different magnitudes of strength. A tiny magnet can overcome the gravity of earth etc
A "predictable past" is an oxymoron. Maybe you mean the "observable" past? There is no such thing as "the present moment" because your present is not my present. The differences may be imperceptible but they are nevertheless measurable. Every observer has a unique world-line because of "locality" (two particles may not occupy the same space at the same time). Quantum observations are never "instantaneous" but are measurements of things that already happened.
Time and Space are an illusion humans are wasting their time by studying the observable universe,,the thing is that we cannot imagine and define things that are out of this world similar to computer AI whatever data you give to computer ,it only play and give information within that limit ,computer can give you new insight but within the range of data we provided but can not generate new ideas beyond the scope of data provided ,similarly this world is our box(data) we are only creating new information by combining the information that are within this world ,,we can not define and explain things that we have not seen before.
Time dilation IS the detection of an addition spatial dimension. Here is a great video about it: Chapter 1-4: Rethinking General Relativity as 5 Dimensions of Physics - A Unifying Theory of Gravity
Space time is space and time space is needed for anything to play out within time and time is needed for anything to play out within space. That why there the same thing know as space time. Space never ends but everything that makes up the universe does and the expansion of space is not expanding but is already there and matter is expanding within it.
When we speak of _space curviture_ it seems to me that this implies higher dimensionalty. That is, how can you curve something if you don't have at least one extra dimension to curve it in? One of the seminal books I grew up with was Flatland. Which explored a people constrained to a 2D plane. That plane may very well be curved, but the Flatlanders would never know it. But we, from our 3D perspective, could plainly see that.
A space can be curve, meaning it may have curvature properties, without requiring the existence of further dimensions. However, it may eventually be simpler to describe it if one does consider further dimensions. I mean, what's so special about orthogonal straight lines but their simplicity of use by our minds? The issue is that the concepts we use to describe reality should not be confused with reality itself. In that sense, Earth may very well be the center of the Universe, it's a possible but highly inconvenient description that would only go against the Occam's Razor Principle.
The more and more i see people like you i wonder why can't i explain things like these people.This is how education should be! Everyone should be able to visualize and have curuosity to ehy that happens.You re one great tutor❤
You want your education system to be based on deceptions and BS? Physics already had a canvas to use as a framework it was just 3d space and also time, but now they have invented an impossibility spacetime, and its messed up rational physics. This is of course, on purpose.
I've been having to make various appointments recently, and the point is when you make an appointment, you need four pieces of information: the cross streets, the floor number and the time. So, they must be part of the same thing.
I am so impressed my the way you explained that i hit like button and subscribed spontaneously. Hats off to you sir. You are by far better than many as i keep watching such content. From Pakistan
I've been wondering if divisional algebras which work only in 1, 2, 4, and 8 dimensions has something to do with space time. Also I read something, not sure where, that in hyperbolic geometry that what might be time dimensions have to be smaller in number than space dimensions, that the smallest number of dimensions which works is 4 dimensions. And perhaps why space-time is 3 dimensions of space and 1 dimension of time. Now that might be just the geometry of space-time. But does that still tell us what space-time IS? What it's made out of?
Before watching this video, I thought we need to consider the velocity of the object along with time and distance. So we need time as fourth dimension. But now I clearly understood how it is related and used. Thank you.
I like that you point out that 'time' on the surface of earth is slower compared to an identical clock in unaccelerated space. However, gravity doesnt 'curve' spacetime, it pinches it in to the core of the gravity well (the earth in this case). Any 'curves' or orbits have to do with the other object's speed relative to the earth's gravity well. Light gets bent very little as it races by our dimple of a gravity well. As a contrast, a person standing on the surface has their curved spaacetime starting at the top of their head, out their feet and running straight to the core. Our way there is blocked and that's why we feel 'weight' The way to the center of the core is blocked because matter under acceleration stratifies by density with the heavy dense stuff at the bottom and the light atmosspheric gasses at the top. What would have been a nice touch in the video would be to further the explanation that time is fastest in unaccelerated spacetime, it's slower on the surface of the earth with our meager 9.8m/s2 acceleration and it is most definitely slowest at the core. assumptions of Newtonian weightlessness at the core are not considering this reality. The densest elements migrate to the core, while gasses go up. Acceleration is greatest at the core and time is slowest.
Really great video! There were moments where I felt like I might actually be able to understand some of iat a novice level. Maybe watch a 10 or 20 more times. Not being cheeky here… I’ve been banging my head against this wall for years, just a really hard concept to a simile. May just have to check out that brilliant course.
Wave particle duality. Wave in space, particle in time. The uncertainty principle. Position in space, momentum in time. Or is it the other way around? The amplitude of a quantum wave function is a complex number. Which is the imaginary part? Space or time and when?
Nicely put, although it should be mentioned that c equivales to the speed of massless particles, not especially photons. If would happen that photons have mass, then their speed wouldn't be c.
I do wonder a little about the extra time dimensions sometimes. It seems permissable for string theorists to posit extra spatial dimensions that loop back on themselves on small scales. So why not posit extra time dimensions on very small and/or fast scales? anti particles already kinda look like they go back in time from a certain perspective. I know there is so much I'm missing in this conjecture but would appreciate what avenues to go down to understand why it wouldn't be feasible.
They probably exist on a quantum level, based on string theory. As mentioned in this video, they might be unstable on a large scale. Thus higher dimensional life forms might exist on a quantum level based on particles we haven't discovered yet. Those life forms may not exist as how we know it, they might have a different concept of existence that we yet do not understand
@@GokulRaamthelegend I wouldn't go as far as life forms. All of our current understanding of life necessitates macroscopic structures well beyond the remit of QM.
Having two time-like coordinates will make it so that energy is no longer conserved, and you will never be able to get two things to stand still (be at rest) with respect to each other. There are at least two string theories with multiple time-like dimensions, and they predict things like protons decaying into heavier neutrons and stuff. Also atoms can't form, because you can't get protons and neutrons to stick together (stand still with respect to each other).
@@juliavixen176 we already know from GR energy isn't strictly conserved. E.g. redshift photons. I mean it's still conserved as far as time translation symmetry is upheld, by Noether's theorem, but GR breaks that symmetry routinely. Also AFAIK zero-point energy of the vacuum is still an unsolved problem and potentially linked to the negative pressure required for the spacetime expansions we currently observe.
@@juliavixen176 I mention zero point energy in response to your statement about not being to get two things to stand still w.r.t each other. As in by Heisenberg uncertainty we can't get things to stand still period! And the energy associated with this is somewhat poorly understood atm and leaves room for zany theories such as extra time dimensions. Well I guess people that know more than me can rule it out, but I'd like to be pointed to resources that tell me why. also sorry for the somewhat unclear initial reply, I'm responding on my phone and the app doesn't let me see your comment as I reply
1. Time is a concept only (i.e. what enables us to think efficiently and collectively about the relative movement of any number of objects). 2. An object is at rest relative to it's self (unless it's being squashed in e.g. centrifuge or rocket). 3. Acceleration and gravity are strongly related but gravitational acceleration (of falling object) affects every particle equally whereas centrifuge or rocket acceleration tends to squash an object. 4. The twin returned from a relativistic space journey would be the same age as the twin who stayed home if the home twin had been kept in a freezer down near absolute zero for some fraction of the duration of the space faring twin's journey. What does the fact that the reunited twins would be the same age (i.e. in the same biological condition (assuming technology capable of freezing/thawing bodies without damage)) tell us about what's *going on* in the body of the space faring twin on his journey? Perhaps the total amount of movement of his particles, relative to his other particles, is simply less and this because particles have a limited amount of movement possible for them and some of that movement is 'busy' in the direction of flight?
Another gorgeous and informative video, Arvin, thank you! It is my understanding that the vector cross product, which is key to maxwell's equations, does not work in 4 or more spatial dimensions. No one ever seems to bring this up as an explanation for why we experience 3 dimensions. It's this a valid argument as to why, or is there an out for higher dimensions for electromagnetism?
@@axeman2638 "Spacetime" does not imply that time is a spatial dimension. In fact it explicitly states otherwise, as they have opposite signs in the equations. You can kind of interpret that as stating time is an "imaginary" spatial dimension, but its certainly not stating that "time is a spatial dimension" in any meaningful way. It might behoove you to try understanding concepts before arbitrarily calling them nonsense.
> No one ever seems to bring this up as an explanation for why we experience 3 dimensions Because we don't control the universe. If the universe had chosen to give us 4 spatial dimensions, certainly Maxwell's equations would be meaningless. But intelligent beings in such a universe would simply come up with some other equations that describe their own forces (electromagnetism as we understand it wouldn't exist, but some other force that follows 4D-enabled rules would exist in its place). Of course that's all speculative philosophy. The universe does have three dimensions and our equations do work, so its little more than a thought experiment to imagine higher dimension universes. But the first step to such an exercise is realizing that _everything_ we know would be different - the particles, the forces, and the math we use to describe them. Everything The ones we know of in our 3+1 universe all explicitly require a 3+1 universe and wouldn't work in any other universe. But some other completely different particles and forces (and math) might. People have of course tried to formulate such things, with middling success. There's a general thought that its not possible because we can't make the math work but that in itself is exactly the problem I'm pointing out - just because _we_ can't do it doesn't mean the universe couldn't have. But its very hard for us to separate the idea of a universe that can't exist (based on the fact that it doesn't) from a universe that "can't" exist (based us fallible humans being unable to figure out how to make our equally human mathematics work for it).
@altrag yeah you can stick your condescending smug face where the sun don't shine mate. I know the official story pretty well thanks, perhaps even better than you, it's rubbish, Space does not warp, it has no substance or properties, it's no more or less than the distance between things, it's flat and euclidean. Einstein is bunk. Equations are not reality.
I'd like to point out that Modelling Causality as a Poisson Process (events on a time line w/ exponentially distributed inter arrival times) we are transforming from the Bayesian into an exponential form of causality (np=t*lambda), e^mean*variance and plotting 'open point' on the timeline allows for a least Paths solution to A QM Model of Causality I refer to as the 'Temple Model of the QM of Causality'. The open point on the timeline represents the 'Temple' State Space Model itself. It allows the 'user' to apply the same exponential transform to the 'other parts' of the model. We can manipulate causality even w/ a pair of dice.
The (very simplistic) way I look at spacetime is that space is a computer monitor and time is the ‘refresh’ key which allows more than one thing to happen in any given point on that monitor. Imagine how much bigger the monitor would need to be if we needed a new section of it for each new window we open.
@@Jake-rj4dx simulation argument is really an escape clause for those that dont believe in god. Basically confirming that a superior being has created this idealistic program / universe / reality.
Your Minkowski graph of the math of spacetime is a powerful teaching tool. I wonder if space or time can exist at all without each other. If there was no time, how could a place exist? If there was no place, would time have meaning? Are time and space inseparable? 🕳
I always thought about that. I came to the conclusion that no, they can't be separated, but at the same time, space is more important and central than Time. Time is a consequence of energy. To reach that conclusion, I used my naked imagination: Imagine you have a superpower: you can freeze everything to the quantum level. Now I want you to freeze this universe completely, until no electron can move, no virtual particle pops up in the quantum field forever. In this scenario, you'd still have space, wouldn't you? With your mind's eye, you can still see the oceans and forest and planets completely static. But time would be gone because it would literally never be capable of passing. Now, try to begin to imagine anything to conceptualize time without space. You can't even begin. You can't even think or imagine a superpower or anything. A vaccum? That's would be a space. A true vacuum? That would be space again. A black universe devoid of anything? Still a location in the grand scheme of things. So space is the basis and time is the property.
@byamboy It's this type of reasoning that makes me think Roger Penrose's idea of a cyclic universe is the most likely theory (ofc my opinion means little lol.) When true heat death finally happens and all the blackholes evaporate, time will be meaningless. No how matter how unlikely something is, any possibility of it happening will mean it will eventually happen. Even if takes 100^1000^100000 years to happen.
Well you can think of them separately, as you can think about x or y direction in space. Space without time dimension would be just a frozen moment of the universe. Time without space would be a blank and EXTREMALY boring existence with nothing to see or touch or experience.
La elementalidad de las ideas de tiempo y espacio, nos impide o dificulta hablar de ellos. No se pueden definir sin caer en redundancias o círculos viciosos. Así, el tiempo es el intervalo que transcurre entre dos eventos. Espacio es el ámbito que habitamos. Propongo un nuevo término designar tres cosas fundamentales, que no tienen definición, es el término EXTENSIÓN, para esas tres magnitudes fundamentales, o magnitudes dimensionales fundamentales, ya que de la EXTENSIÓN, se derivan, el espacio, el tiempo y la masa. Que son tres cosas extensas. Porque pueden existir en el Universo y podemos referirnos a ellas como existentes. Porque los podemos estudiar porque muestran propiedades diferenciables, de una con respecto de las otras. Porque las podemos medir usando instrumentos diferentes. Porque acceden, de alguna manera a ser percibidas. Porque podemos cuantificarlas y los cálculos.que hacemos son congruentes. Pero que nos intrigan cuando tratamos de verlas individualmente; es decir, darles calidad absoluta de existencia. Porque, aunque no se haya dicho, la masa también es relativa al espacio y al tiempo, ya que incrementa con la velocidad o energía cinética. Incluso, se origina de la velocidad misma, se genera a partir de bosones que corren a la velocidad de la luz. Entonces la EXTENSIÓN, puede asumir el papel arquetípico o primordial, con respecto de esas tres modalidades de entes diferenciados pero relativísticamente asociados.
@@byamboy I can easily imagine a black universe devoided of anything, but I can still suspect there is some kind of time, since even this dark universe devoid of nothing, is something. So Space is the bases and time follows as a property.
Information is everything they say and some say everything is information, the foundation of reality. Space contains all the information and time is reading it.
spacewalks are recorded by professional divers in the NBL. The truth is they are more like waterwalks vs outer spacewalks but where is the magic in that!?!
Your analogy is revealing: we do have Space and Time because we built equipment, to define Lab frames (Buildings, roads etc.) and clocks to define Time (synced with satellites etc.) , allowing to fit a Mathematical Model (R3xR), which needed "stretching time" and compress distance (Lorentz transformations) and adjustment in the presence of the real, Natural "frames": matter (GR). After 70s we started understanding it is a Network (Quantum Computing); it became apparent it is Adaptive (QFT interactions, Chemistry etc.). But Classical Physics still needs it (S-T). Otherwise the building "pixel of Universe", the leggo block for the Universe, is the Hydrogen atom: 3-quark directions (RGB) to define local Space and a spectrum of frequencies, as a metronome to keep the beat (Pythagoras would have liked this). (see Yewbzee too :). Now, due to Gauge Theory, we understand how 3D-Space and Time emerge, and "look as if related" (2x2=3+1: SU(2) "thing").
Here's why there can't be more than one dimension of time: when we talk about time we're actually talking about the 'rate at which causality happens'. And causality is ultimately a "spatial" phenomenon: it's the rate at which events can happen in space - for objects to move and interact in space. So really it doesn't make any sense to think of time as separate from space. Spacetime is the only thing that makes sense. Spacetime is space + causality.
11:40 If I travel in the past and kill my father, then he would not be alive to meet my mother. So now I am never born to go back into the past and kill my father which means now my father lives and does too meet my mother. My mother then goes on to give birth to me, so I grow up and travel the past again and kill my father again. Now I am never born again and I do not go back to kill my father again. So now my father lived again and meets my mother again. Now Ill be born again and the cycle repeats itself forever. This causal paradox is possible, it just means I will forever be stuck in this time loop. Every time I kill my father, the very next moment in my future is me being born again.
@@noidontthinksolol There is nothing else than clock time. The rotation of Earth alone doesn't create time. Time requires the communication of the state of the clock to an external system, i.e. an energy transfer. In case of a rotating planet that's a very, very small loss of energy, which makes rotating planets reasonably good clocks.
I know Chris "The Brain" said in his video on space time, "Chapter 5: What is Time? Special Relativity, Inertia, Wormholes, Anti-Gravity, Time Travel, and FTL" That the relationship between space and time were contridicular, and that there is an absolute zero velocity that we should build a unit to find.
Clocks running slow doesn't mean time is different. There is only one 'now'. Calculating a difference your clock shows doesn't show anything about time.
There is no such thing as "one now" -- the "one now" that someone on Pluto describes would be different than the "one now" you describe because Pluto is moving faster than earth. When you say, my now is "now" - what does that even mean, because there is no way for you to communicate in the very instant that you say the word "now." Even when you are talking to a person across the room, the "nows" are different for the two individuals because it takes a small amount of time for you to see the light reflecting off of them. This does not make any practical difference because the time difference is so small that you do not notice it. But on cosmological scales, this communication speed limit makes a difference in what you can possibly describe as a "now."
@@ArvinAsh Just because you can't perceive every point in space at the same moment doesn't mean it's not currently experiencing the same now as a current observer - heck you don't even get to see 'now' since it takes time to propagate through neurons... At some point in the future you will observe its state that occurred at the time in the past that it experienced the same now as you (again not that you would see that) There's no evidence to support that there is any more than the current instant happening in the universe - observation of that is of course limited by propagation delays of that information. There's certainly nothing that has already happened tomorrow or at any time after 'now'... everything that is perceived is from a time in the past from any observers point of view, but that again doesn't mean it hasn't already had many more interactions already between the time you see it at, and the time it is at when you are seeing it. It's actually observable... light travels about 1 foot in 1 nano second. Computer clocks tick at 1Ghz+... 1Ghz is 1 cycle per nano second... so every N feet of distance is also N nanoseconds in the past from your point of view... When dealing with a hardware device in the 90's I got to learn just how long a nanosecond is... putting the card on 6 inch extender on an ISA bus delays the signal about a nanosecond (since electric signals really only go about half the speed of light maybe more, i've seen more recent approximations that it's 70-80% of the speed of light, but given the amount of capacitance a signal has to fill before a signal can actually be detected 50% is good enough; that short distance started causing it to fail on certain motherboards. But certainly every signal that went 6 inches was perceived from a ( it's not 'now' at that point it's a past now that the signal was generated, before it is observable at a time after it was generated... but still that card is generating signals in the 'now' that will be seen later). There's certainly no evidence that anyone is stuck in the past, any more than that events have already happened after now.
As you said, how the time and space can be the same while the units are different. At the same time you have also said that the concept of time is developed by us humans. In my local context the time is calculated into the distance of the sun's movement in the sky and there are around several units of time within 24 hours. For example the smallest unit of time is 'badany' means a step. Jill means when the sun rises. Pari means when the sun moves up in the sky around an hour after it rises. And papan means the mid day. In this way, the time is just the same as the distance.
Sorry, but I believe that Newton was right and Einstein is wrong. Einstein's THEORY has never definitively been proven! All you are doing is regurgitating unproven rhetoric.
I believe space, and time are relative to each other, but they are experienced differently by different people differently, as well as the past, present, and future are relative. They are part of the same thing but yet separate. Much like when two cars driving down a road each at variable speeds, in opposite directions... As you drive forward looking ahead you perceive another car traveling towards you. Both speeds may be exactly the same, or might be variable. You are looking at the future at that exact moment where you will be as the other driver is looking at the future where they will be. As time progresses the space between you both decrease, and you both travel closer, and closer relative to each other, and at some point you both exist in the same area of space, and time, experiencing the present even if for a very quick moment in time. As both cars go past one another, you each look into your rear view mirrors, to see each other move away at variable speeds, and now you both are looking into the past from that moment of each others present. As time progresses, space appears to expand with each car moving farther, and farther away till you do not see each other no longer. Even tho you no longer experience each others presence in your current state of perception, you still both exist, and are relative to one another. Its like the tree that fell 1000 miles away that you never perceived to have fell, and never heard. Did it truly fall.. Yes of course, since your space, and time are relative to that trees space, and time. The relative of space, and time are both experienced differently based on your perception. In the above examples, time, and space has not changed, or has it? Even tho you seen each other in three different states of existence future, present, and past, you still exist, even after not being able to see one another. It can be argued that does the same space, and time exist in the same present in two different locations of space, and time. Now if both of you were to turn your cars around, and travel back in opposite directions, your path should cross again only to repeat the above. Can it be said that the same space, and time exist, and are of the same thing.. lol. As you both travel towards, and away only to repeat going back towards each other is space expanding or contracting? Is time reversing or continuing? Does time really exist or is time made by a sense of perception. Space can change, and is in constant flux, but does time flux? Time to me is pretty much man made unit, to express ones sense of perception. For example like standing on the edge of a road with cars going by constantly in rush hour traffic.,... As you stand there you experience time on your own level of perception, where as everyone zooming by is experiencing time on their own level of perception. Time may still be relative to everyone in the exact present moment, but it fluctuates over time concurrently. Can it be then said time is the same to everyone even if experienced differently by different people. Now lets take this one step further. Its already proven that when we see it takes approx 2 seconds for the mind to process the information, but with age it takes a bit longer which is why elderly, and young people process thought, and what we see at different speeds, and are much slower or faster to react towards situations while driving differently. So if a person older perceives things slightly longer say 4 seconds where another younger person did so in 2 seconds can it be said space, and time are of the same thing. So when two people are driving of different variable ages, that process information at different speeds, do space, or time change for either of them? Yes it does...... The amount of time taken to process the information of space, on future, present, and past are at differential speeds of time by two different people. Space however remains the same and constant flux.Time is basically an illusion but it is relative to the constant flux space. For example two people as above both traveling by car but each doing something completely different, one person is smoking a cigarette while the other person is flashing the bird. Both see each other but 2 seconds apart, and differently so space, and time are not of the same thing. But are they are relative... Sorry... lol
Thanks for making me to understand to certain extent cause I am just medical professionals, head and neck surgeon, retired Prof, age 76 years ago. I am from Burma (Myanmar). Thanks again. Yours sincerely Dr KMA ENT
Very nice explanation using the speed of light, time and distance equation to show space time. Time Dilation effect: gravity effect is weaker than speed effect. Could that be related to gravity being the much weaker force compared to the weak nuclear force and the strong nuclear force, which is where photons and speed of light come from? The forces are different, so their effect will be different. Is that why gravity has a weaker effect on time than speed has on time Looks like all the things are directly related: forces, time, distance, mass, energy.
Gravity is not a force. It's a measurement. It's like saying temperature is a force. Non-static measurements are measurements of acceleration/motion. The law for determining the amount of force in the system is Newton's Law of Motion F=ma. Mass is static. It's length, width, height, volume. Acceleration is what gives mass force. Gravity is the measurement of the force being applied to accelerate the mass in space. Temperature is the amount of acceleration the mass has in time. For time, you can use E=mc. Atomic energy converts to radiant energy with acceleration. When an atom gets to c, it becomes a photon. It still has mass, radiant mass that is, in the form of length. The photon's wavelength is its mass factor. (c) is the speed of light and E or F is the Force factor. As the photon's wavelength increases, it's force factor decreases since force decreases with distance (longer wavelength).
@@stewiesaidthat if gravity is not a force then why is it measured as F = ma, where you can measure gravity as mass x acceleration due to g (gravity)? I see that Einstein spent 10 years struggling with whether gravity is a force or not, and eventually said it's a result of the effect of 2 body's mass acting upon each other and the amount of space-time they curved. Something like that. It's taught in school as a force. In every day life it's treated as a force. Where do you use it not as a force but as a curvature of space-time?
@@Google_Does_Evil_Now Gravity and Temperature are measurements of acceleration. Gravity is the measurement of how much force is being applied to accelerate the mass in space while Temperature is the measurement of how much acceleration the mass has in Time. F=ma/E=mc. Acceleration in Space/Acceleration in Time. Mass is just stored energy so F=a/E=c or Force equals Acceleration/Energy equals Acceleration. The difference between Atomic energy and radiant energy is its Acceleration factor. Everything in the universe is then defined by its Acceleration factor. Which means the Proper frame of reference is the acceleration factor. The earth spinning on its axis, the frame of reference is the zero acceleration factor or its axis. Because the earth is spinning, it's mass is being accelerated not only outward but also forward causing curved space. As the radius from the center increases, so does the acceleration factor. F=ma. Since the Force (Earth's rotational speed) remains the same, the mass the must decrease in value. This can be observed by the thinning atmosphere with an increase in altitude. The Earth's mass is not being pulled inward but accelerated outward. This has been verified with synchronized clock experiments showing that as the radius increases, so does the acceleration factor. The earth rotating on its axis creates curved space. If mass does no create Acceleration, then what does? If you go back to the big bang, you will see that its an acceleration event. Current theory says its both space and time but logic dictates that it was a Time event. The point that un-accelerated energy transitioned to an accelerated state. Energy can be neither created nor destroyed, only transformed. That means space always was and that the current state of energy (accelerated) was in a different state. What causes planets to orbit stars, stars to orbit black holes, galaxies to move through space? The logical explanation is an energy imbalance. The same energy imbalance that creates hurricanes, tornadoes, typhoons. Space is an ocean of energy. Planets and stars are just clumps of that energy that became attracted by electromagnetism. The laws of physics are the same for all frames of reference. As QM has shown, packets of energy react to differences in electromagnetism. Electromagnetism is the attractive force. Gravity is the result of an object being accelerated on space. An object that accelerates itself does not experience gravity as there is no outside force acting upon it. This was shown by the hammer&feather drop tests. The mass of each object had no influence on the acceleration factor. The object in the air has a +5 acceleration factor than what the ground has. When the hammer is released, it is no longer being accelerated at the +5 Frame of Reference. Since an object in motion stays in motion unless acted upon by an outside force, the ground (moving through curved space) is following behind and Impacts the hammer. The same as when an object falls off the back of the truck and hits the trailing vehicle. Newton was right about the apple falling being a difference in Acceleration factors. What he didn't understand is why. The mass of the earth doesn't curve space, the motion of the earth (spinning on its axis) is what creates curved space. This is something Einstein never understand. If you listen to Sean Carroll's podcast on Einstein, you will see that Einstein didn't really understand physics. His biography is littered with examples of plagiarism. He stole other people's ideas, had no clue how they worked, and cobbled together his Spacetime fantasy universe using relativity as the basis for his physics. If you check, using acceleration as the proper frame of reference, you will see that relativity is 180 degrees from reality.
Kindly let me know the answer for the following HYPOTHESIS please. SCENARIO 1. Only INDIA EXISTS as ISLAND. 2. Other countries are submerged How Is it feasible to have 1. ONLY SPRING season 2. 24X7 Sunlight in INDIA for 2500 years ?
"If it was anything else, the universe would be unstable!" That's such a silly argument. Certainly if it was anything else the universe would not function as we know it with things like inverse square laws. But that doesn't mean there wouldn't be some other type of universe that wouldn't work. It would just need different forces that coupled in different ways. Would certainly be unfathomably different from what we know but that's not really relevant as we wouldn't exist in such a universe to begin with. A more interesting argument (IMO) is "this is the simplest possible configuration", as the universe generally seems to prefer simple structure over complex at the most fundamental level. There is good justification for 2 dimensions of space not being "enough" - things would have a hard time moving passed each other (and in a 1D space it would be impossible) while 3D gives lots of space to move around in well.. space. A 4D space would work (in some manner) if forces dropped off with an inverse cube law rather than an inverse square law (and 5D with an inverse quartic law and so on). But those extra dimensions aren't "needed" in order for objects to move freely in the same way that the third dimension improves over the second. That's all more philosophy than science of course. We have no way to really know why the universe is the way it is. Its all just made-up justifications to satisfy whatever we want to believe. In my case, I don't feel comfortable telling the universe what it can or cannot do. It can do whatever the hell it wants and our only role is to try and understand it after the fact. The argument that the inverse square law would fail in >3 dimensions for example is subtly demanding that the universe "must" use an inverse square law, but there's just as little justification for that demand as there is for directly demanding that it "must" have 3 spatial dimensions. Physically a meaningless distinction (the universe does indeed have 3 spatial dimensions and an inverse square law) but philosophically problematic - again, IMO.
Space and time don’t exist in themselves, but represent the relationships between all that exists in the universe. So it makes sense that they would be connected in some way.
0:20 Spacetime is not just a background. It's not a matter of having painting colors with no canvas, it's really about recognizing that colors and canvas are really the same thing, and neither can exist without the other. At the largest scales, matter tells spacetime how to bend and deform. At the quantum scale, wrinkles in the fabric are what makes matter emerge. Together, the two theories complete the circle, which is the fundamental reason why unification efforts have failed thus far. There's nothing to unify. The two theories are different ways to look at the underlying reality. If we want to understand black holes better, we need to understand what exactly quantum mechanics is telling us, and not just "shut up and calculate". We desperately need an onthological basis for quantum mechanics, just like we have one for GR.
While it's simple to just say "large dimensions" to exclude the compact dimensions of things like string theory, it really raises the question of how spatial dimensions can come in a variety of "sizes".
Easily; they are distinct parts of one and the same concept (in reality). 'Space' is simply the distance between two material objects (what fills that space is another matter). And 'Time' is a particular measurement of these two objects across that space, i.e. generally in so far as they pass each other, or specifically in their mode passing, e.g. trajectory (one may have an oblique course) and distortion (the other may have a turbulent passage). The concept remains the same, but the description differs .. including any wibbles and wobbles as part of the whole, they are the special bits of the specific account. Yey!
13:20 it's not that we happen to live in precisely such universe, but life could have formed in only these 3,1 space time dimension universe only, so if life exists then universe has to be 3,1. Otherwise there would be no life to perceive it. Therefore no life form has ever perceived any universe other than 3space 1 time dimentional universe.
That's essentially a version of the anthropic principle. I'd add, in addition, that life AS WE KNOW IT could only exist in 3,1 because life AS WE KNOW IT evolved through chemical chance within this universe - there's no reason to think that life couldn't, theoretically, come to exist in a 4,1 or even idk a 7,4 universe, it just would not resemble our life at all!
@@MaeveFirstborn yes, true. Universe with different physical laws can sustain life with different biologies. Maybe our own universe can sustain different kind of biological evolution about which we might not aware of.
I view time in 3 dimensions as well, but each point represents a single energetic state of the entire 3D space. This means time not only goes forward and backwards, but also sideways and up/down. Sideways can represent different versions of one dimension, while up/down represent parallel realities. What people assume as time being a single 4th dimension of space is only because of the assumption that there is only 1 real timeline, what one experiences within space. This is why formulas based on a single variable "time" works because the formulas only apply to a single linear point of spacetime. One couldn't easily validate the results outside of this one experienced timeline. But that is an assumption. What people call "string theory" can be encapsulated by the idea of a 2-dimensional representation of time, but it ignores the alternative version concept of each individual timeline as the 3rd dimension of time (the choices not taken by one version, is taken by an alternative version of the same reality). When space "bends" time, all that means is that the rate of change in space is a relationship to the rate of change in time, meaning the 3-dimension of time is itself encapsulated in a higher dimension of something related to time. When you accelerate in space, that means the number of units of time that changes is done quicker in the higher dimension of "experience of time" or "rate of change". From my perspective, that higher dimension above time is consciousness (it encapsulates these dimensions of awareness). The awareness of change, which is a function of time, is why the perceived change in space/time is relative. It depends on the point of view. Without different points of views, there would not be general relativity.
Unified Spacetime decomposes uniquely into 3 spatial dimensions and 1 temporal dimension for every observer. It brings up the interesting problems again of what constitutes an observer, and what constitutes an "event". Intersection of world lines? How does that work in QM? Surely not point-like. An "event" has to be extended in some sense, with dimensions in space and time. And it's hard to imagine a point-like observer. Things seem to get blurry. The way Spacetime decomposes seems to be necessarily blurry. So at some scale the three spatial dimensions are difficult to quantify, and so too for the temporal dimension.
Thank you for taking the time to explain spacetime but there is something that to me as a non-physicist (but a biologist with a PhD and much research experience, so a scientist) seems confusing. Someone travelling in a spaceship and coming back should have aged less than someone on earth according to your description, even though during that time the earth has been turning around itself and around the sun, as the solar system has been travelling around the galaxy, which has been travelling through space. So there is nothing constant and arguably the person on earth has had a more twisted course, possibly with all kinds of acceleration and deceleration added in as the universe is expanding and space is dilating with everything else moving in it in varying speeds in relation to other reference points. So the person on earth is perhaps travelling more and in a more twisted path and within higher gravitation fields than the person in space going in a straight line and back. Additionally, what absolute time on the Y-axis is also makes no sense. Movement on the Y-axis with reference to what? Besides, the space-time cartesian system is some kind of anti-Euclidean geometry where a kind of a reverse of the Pythagoras theorem applies. And in all this non-Euclidean weirdness, the only thing that we can rely on as being constant is the speed of light. In terms of what reference? Are two photons moving in opposite directions moving at the speed of light in relation to each other? C+C=C? That is an impossible concept.
For the first one, lets say that the man on the spaceship managed to escape the gravitational fields of the entire Solar System. While the man on Earth would have traveled around the Sun, and also around the Milky Way during that course, the man on the spaceship would need to catch up to him. He went far away, and now he needs to travel even more to catch the man on Earth. So he doesn't just "go and come back"
@@ningninglvr48 - They are both moving through space, they are both non-stationary and eventually meet up. They both travelled a lot before meeting again. It would be equally arbitrary to say the man in space is stationary and the space and galaxy and our planetary system moves around in a twisted course through the universe until we catch up with him. If we move away from a dstant galaxy, our galaxy should be aging more slowly. But at the same time, the distant galaxy is moving away from us. So the distant galaxy ages more slowly. Can both be right?
Spacetime being one thing makes sense because it takes time to move through space. Conversely it takes space to move through time. Which is why time supposedly stops in a black hole where there are no dimensions.
The simple explanation for the formula "E^2 = t^2 - x^2" is that the factor between time and space is i (imaginary unit) times c (speed of light). Then you can use the Euclidian distance again: (E i c)^2 = (t i c)^2 + x^2
In Einstein‘s paper, on special relativity and a problem with speech he states for one object there is no time or space. For two objects you can take equally like measuring rods. and measure a space between them you can then how to text of the clock and know how long it took you to lay down the rods. Space is a measurement between objects time is a measure between events. Space-time is a metric system to figure out this patient time of events
Time is often conceptualized as a series of cycles, and not strictly as a linear dimension. If you think of a dimension, you're essentially referring to an averaged set of cycles. While many things in the universe might seem to operate on nearly identical cycles or "times", each has its own unique bubble of time. These bubbles might be very similar, but they are distinct. Thus, it might be misleading to label time solely as a dimension. Comparing time to numbers, it's like equating 99.9999999999 with 99.9999999998 - they're incredibly close but not the same. The best we can do is make predictions based on averages, but treating these approximations as absolute truths might be an oversight.
In the realms of science, where wonders abide, A mystery unraveled, where two concepts collide, Space and time, entwined in a cosmic dance, A question that challenges our understanding's stance. Einstein, a visionary, paved the way, With his theory of relativity, night and day, He showed us a truth, both profound and strange, That space and time in nature can surely exchange. Space, the stage where the universe unfurls, Time, the river where existence swirls, But how can they merge, these dimensions so vast? A concept that leaves us in awe, steadfast. In spacetime's fabric, they're woven as one, A fusion of realms, where the cosmos is spun, Gravity's influence, a force to behold, Bends spacetime's fabric, as our tale is told. Black holes, where this fusion is clear, A singularity's pull, both far and near, The bending of time and space, a cosmic ballet, A phenomenon that leaves our minds in dismay. So, let us embrace this intricate weave, Where space and time together, they cleave, In the tapestry of the cosmos, their mingling's sublime, A profound conundrum, standing the test of time.
I've seen countless videos and explanations on this topic. But I always fall back on thinking that time as a dimension is a weird way of interpreting what we see. Hear me out. I don't think time is a dimension at all, but an emergent phenomena from "light speed" particles interacting in space. There is only space, and in space there are particles moving in a constant way (light speed, C) and interacting with each other. These interactions are what time actually is, there is no dimension to it. The reason we see time flow differently when moving relative to something else, is because when a bunch of particles all move in the same direction, there is less particle to particle movement. Because particle speed is constant, C, it leaves less possibility for interacting movement against each other. And that lessened interaction between particles causes time to flow slower. For example: We have 2 pairs of particles (4 particles in total) stationary in space. Every interaction between the particles is one tick of time. Now a pair of particles starts moving away from the other pair at 0.9 C, while the other pair stays stationary. The moving pair now has less possibility of interacting with each other (compared to the stationary pair) because it has already "allocated" 0.9 C to moving away, and therefore not interacting as much. When the particle pair then compare time with each other again, the moving pair will have had way less interactions and therefore time has moved much slower, but the stationary pair has had more interaction so time moved "faster" for that pair. This is also why we consider photons to have "infinite time", because photons are just single particles moving 1 C (light speed), leaving zero room for interaction until it collides with something.
That’s a lot of difficult key concepts packed into one easier to understand video, bravo! 👏
Space and time are relative, the more time I spend with my relatives the more space I need
In fact, the ratio is inverse. Wrong.
That is precisely an inverse ratio.@@richardparker1338
"Actually" kid in the comments. It's a joke, let it be.
@@hooked4215It's a joke. Stop.
I have stopped a long time ago but you have kept moving so you think that I am the moving one.@@ashhole03
Wow, I just happened to come across this video and I found the explaination super helpful with such a complex concept (you can tell that I'm not a science major here). The use of interactive graphics really helps guide the viewers to have a better understanding of the talk. But the real genius is how Mr. Arnold breaks the concept down and use simple languages to clarify the complexities of space-time (I'm still not there yet but may be I will someday). STEM students can truly benefit from this type of education. I'll definitely keep following this and hope my granddaughter will benefit from this someday, should she chooses to go into science/engineering. Thank you.
My favorite concept which I read way back when I was in Junior High school is that "when you travel at any speed you trade space for time." You gain time (time dilation) and you lose space (length contraction).
Continuous acceleration 🤔, as it makes no sense if the graph is constant
Good explanation. In my opinion, space does not contract, but rather the travelling object simply viisits less places the faster it goes. If it had to visit all places between the start and end it would have to visit anifinite number of them (because you can always sub divide between two points), which would take forever. Zenos paradox about the movement of an arrow first highlighted the infinite number of points between any two places. Modern maths makes a pathetic attempt, by inventing the concept of limits (where the crux phrase is 'at infinity', which of course can't happen), to show movement is possible if you draw a line of ink on paper, the ink will not be contigous, and the faster you draw the line, the less places the ink will mark the paper. I think it's the same for spacetime. The faster you go, the less places iyou 'visit. It works the other way too. The faster you go the less points of time you vist, so it seems time contracts. Time dialation is (in my opinion) when points in time are skipped over just like the points in space. 🙂
@nswanberg replying to whom? Please mention
@nswanberg not moving at all isn't the slowest you can go in space, correct? Extreme curvature of the space you're not moving in also plays a role in how "still" you are to outside observers. I propose you are more still relative to the rest of the universe while you are falling into a black hole, despite the presumption that falling is moving. It isn't in this case -- let me explain. When you swap space and time coordinates is when you're most still in my opinion, as falling towards and reaching the singularity is as inevitable as "falling" into the future in any given moment. So movement towards the singularity in a black hole isn't through 3 dimensional space, but through 1 dimensional time. The singularity IS your future, and there's no way to avoid it. You can move out of its way no more than you can move back in time.
So I would say the singularity is the slowest you could move, but what do I know
@@RedNomster Good stuff! Also, the more still an object is it seems, the cooler it is. The cooler something is the less engery it has. So perhaps black holes are the coldest places in the unviverse, with the least energy? Just outside the event horizon then (too adhere to the conservation of energy), there should be all the engery of the particles that pass across it, and hence this would be very 'hot'?
This is EXCELLENT! I have tried to come to terms with spacetime for ages, but Arvin has shed light where no-one else has been able to. Thank you!
I love that you casually gave one of the most intuitive explanations for the twin paradox as an aside for your main subject matter. Your talent and hard work as an educator is so incredibly rare. Thank you.
The video did not cover the twin paradox. It only showed what observer A would see about observer B time. It did not show what observer B would see of observer A time. So it did not show the paradox, that from observer A perspective B time is slower and from observer B perspective A time is slower.
@@yziib3578 it showed that whomever travels in space and returns to that point is younger. How does this not show the twin paradox?
@@Va1demar This is literally the very first thing covered by every single explanation of Special Relativity. Admittedly, some of the explanations suck, but to summarize... actually, I'm just going to go to bed, there are dozens of good videos about this on RUclips that you can watch, here, for free.
@@yziib3578 Both observers agree with each other about the spacetime interval each traveled. If one twin only travels on one side of the triangle, then the other twin *must* travel along the two other sides of the triangle. Spacetime intervals are invariant. Two sides of a triangle are always longer than the third side.
Do the Twin (so-called) "Paradox" with triplets or quadruplets and it should make more sense.
@@Va1demar I struggle to understand your point from a theoretical perspective, but please bear in mind we have an incredibly large amount of empirical evidence for a constant speed of light. As in we go out and measure it under many many different scenarios and it comes out the same.
0:08: 🌌 The concept of space-time is essential for the existence of the universe and all physical phenomena.
2:54: 🌐 The concept of combining space and time into a 4-dimensional continuum called spacetime is not intuitive, but can be understood by comparing it to the geometry of space.
5:31: ⏳ Time and space have an inverse relationship, as shown by the equation E^2 = t^2 - x^2.
8:21: ⏳ The concept of time and its relationship with space explained, including the conversion between the two using the speed of light.
11:09: 🌌 The existence of 3 spatial dimensions and 1 temporal dimension is crucial for the existence of life and to avoid paradoxes.
13:53: 📚 Brilliant offers a practical course on Special Relativity with interactive learning tools and monthly new content.
Recap by Tammy AI
The bigger question revolves around whether spacetime, the foundation of our current physics models, can still be considered the fundamental layer of reality, or if it instead originates from a more foundational underlying structure. While our current models have thrived on the spacetime framework, recent challenges and breakdowns in certain areas have prompted us to question whether spacetime alone can continue to provide a comprehensive explanation.
That's why so many physicists have spent their lives trying to formulate one equation for the entire universe. Einstein has been the closest with E=mc2. But that only says energy must have mass and vice versa. It doesn't account for time, which is relative to the observer. So easy to understand yet so hard to grasp until you grasp it.
I’m wondering if, and how, fields play into this structure? As he has demonstrated in other videos, space is made up of fields, like the Higgs field, and other boson fields. Is there any connection between these fields and the 4 dimensions that our universe appears to have? Matter cannot exist without these fields, so, can we have three dimensions without these fields? I’m not even sure I’m asking the right question.
@@alphagt62 > Is there any connection between these fields and the 4 dimensions that our universe appears to have?
Yes, they're deeply connected. The fields that we describe in the Standard Model only work in 4 dimensions. (Of course you can create fields in other numbers of dimensions, but they would not be the fields of the Standard Model. They would be something completely different.)
> Matter cannot exist without these fields
Matter _as we know it._ That's a very important caveat to always keep in mind when we're discussing these kind of philosophical topics that we can't prove (or disprove) using any known science.
> can we have three dimensions without these fields?
Fields are a mathematical model we humans use to describe what we've learned about reality, but they don't define reality. Reality just is what it is. It existed long before we invented the concept of "fields" and it will continue to exist long after we and our knowledge of fields has gone extinct.
> I’m not even sure I’m asking the right question
You are, you're just asking it in the wrong frame of mind. You need to dissociate what the universe is from how we mere mortals understand the universe (and that's not particularly easy - don't feel bad about it!)
One thing to always remember is that these questions cannot be answered (at least not without a view of the universe from outside the universe, which we're unlikely to ever get). They're philosophical questions rather than scientific, and they're questions philosophers have been struggling with for as long as humanity has existed. Each era within the framework of their own knowledge of course - the ancient Greeks for example pondered their "celestial spheres" rather than our current conceptualization of fields within the Standard Model - but the underlying questions are essentially the same.
Anyway that's enough rambling from me. I'll say you're off to a good start! Happy philosophizing! :D
@@alphagt62so the fields actually are space time. The 3 physical dimensions are just those fields all stacked on one another and that forms the “fabric” of reality
Considering the longstanding emphasis on spacetime as the foundation of reality, it's worth pondering if we've got it reversed. What if consciousness is the true fundamental layer, from which spacetime and all its intricacies emerge? Challenges in our current models might be pointing us towards such a profound paradigm shift. There are many scientists now seriously considering this. Look up Prof. Donald Hoffman and his work on this.
Hello Arvin. You should be made the education minister for the whole world owing to your exceptional pedagogic skills. Schools in general tend to repress creative questions from children. Someone like you would reverse that and then we will not just be finding new answers, but we will also be finding new questions, both of which are paramount for scientific progress.
Excellent video as always. I especially liked you putting a very obvious question 'how can two quantities with different dimensions be equated'. One question: In the video you mentioned that multi dimensional time would allow time loops to exist. How is it then that we humans are trying to invent a time machine in a space-time which has only one dimension for time? Shouldn't it be outrageously impossible?
Yep time travel is impossible just like bending space is impossible
@@chrisstevens-xq2vb what do you think about the proposed alcubierre drive?
@@shethtejas104 Funny asf. You can’t bend space.
@@chrisstevens-xq2vb Ok chill. I was just asking your thoughts on it. Relax.
@@shethtejas104 it’s called being direct….
One of the simplest best presentation of space time. For our future young generation scientist, it is very important to understand the space time concept. It is necessary to extend our understnding of Einstein's Theory of relativity, his EMC² and also the new concepts on Gravitation...is not a force and beyond. As usual, good job from ARVIN.
I love your commentary; it's so concise and ultra clear. Those two things really help me to grasp these complex ideas.
❤indeed
This is such an amazing encapsulation of a difficult topic. I could have skipped dozens of videos by simply starting here!
So how does space bend?🤣
@chrisstevens-xq2vb
Over backwards.😉
@@leeg8461 People actually believe nothing can bend🤦🏼♂️
@@chrisstevens-xq2vb space isnt ''nothing''
Time adjusts itself for each person to make sure light speed is the same for each person/observer ( whatever that is). Crazy
Well I guess that’s to say time is relative to the perspective of each person because it’s limited by the speed of light? So somebody in another galaxy is existing in our future, but at the same time from their perspective we are existing in their future…I need to watch the video again 🧐
Einstein's relativity didn't prove that time is relative. Relative time is only a principle in it.
It's because of inertia. Moving at a constant velocity is exactly the same as standing still. Everyone and everything is standing still with respect to itself, and so relative to itself, it emits light at the speed of light.
@@smlanka4u you are right. There have been, however, experiments that proved it.
@@gaopinghu7332, High-energy muons decay slowly because they are not similar to the low-energy muons. It doesn't mean that speed changes the time. Also, photons experience time even if they don't decay faster, and their wavelenth increases with time. Planck time is not relative.
Dear Arvin sir, you have simplified complex topic to a great extent. Love you.
absolute amazing video im 35 yrs old and always was wondering about space time since school no one explained it better than this video.
Great video! I find it helpful to think speed is converted from time. We are all moving through time at the speed of light. You hinted at the conversion factor… borrowing just a little time and can give you a lot of extra speed
Gravity is constant acceleration so we need speed to overcome that and appear stationary. So we convert some of our time to speed so our time goes a little slower.
No constant speed can "overcome" non-zero acceleration, this part doesn't check out. To compensate for acceleration and appear stationary you need another acceleration, i.e. changing speed, but it would mean changing time dilation.
Nor are we all travelling at light speed lol
@ExistenceUniversity yes we are all traveling at the speed of light. Sorry, but you are wrong. Here is the proof:
ruclips.net/video/au0QJYISe4c/видео.html
From science clic English.
@@Name-js5uq Science clic is wrong. If you were traveling at the speed of light then you'd have no experience of time or space. You wouldn't exist as you do.
In fact you can find my 2 year old debunking of his video in that comment section lol
The short answer is our world is perfect and balanced in any terms,
Arvin, this was a wonderful presentation, made beautiful because of your faith. Your love of creation really came out and really makes this video special (not relatively, absolutely).
After 23 seconds “space time, the canvas, that the Painter with all the colours needed to create their master piece”
And at the end, the fine tuning,
If the universe were any different, one dimension more one less, and we wouldn’t exist
Finally, you gave thanks along with the loving couple gazing at the stars.
You mentioned thanking your lucky stars- but I take this as code word for thanking something else that really does exist. God bless you.
On one hand, this is the closest I've ever come to grasping the concept, so bravo for Arvin. On the other hand, if C is distance/time, then C squared would be distance squared over time squared. Well, I know what a distance squared is (three inches on the sides of a square yields nine square inches), but I can't grasp the meaning of a time squared. What's a square second? This continues to flummox me.
Still, it's the clearest demonstration of the concept I've seen so far, and my livelihood doesn't depend on my understanding it, so I'm satisfied for today.
Maybe this won't help you, but a squared second would be something we cannot intuitively understand, as we don't have the practical experience. Said otherwise, in the practical sense, it has no meaning. Like a meter to the fourth, we don't have the practical experience. What we can do is process it analytically, and maybe it's easier to figure out what a fourth dimension of space might be as we already deal with three of them. Other than that, a fourth dimension of space has no practical meaning.
Another possible way of looking at it, although again it may not be helpful at all, is to consider acceleration. If velocity is the rate of change of distance per time unit (second) and acceleration is the rate of change of velocity per time unit, then acceleration would be the rate of change of distance per time unit squared (squared second).
Or, maybe more properly said, the rate of change, per time unit, of the rate of change, per time unit, of the distance. The analytical meaning(?) here would be that we had to consider twice independent variations in time.
Good explanation. The acceleration example was what occurred to me as well: change in velocity per change in time or change in distance per second per second. Like the gravitational acceleration at MSL on earth, 9.8 m/s^2 for a free falling mass in a vacuum.
You are so smart.
I’m an Electrical Engineering Technician and fully understand what time is now.
Great Video and excellent special effects. 🤗
Subscribed ✔️
Thanks for watching!
I think the oddest, weirdest, and most significant science discovery was by Maxwell. His differential equations showed the speed of light was constant to all observers. That's told us that the universe was one weird place.
Can you explain this? That sounds super logical to me, but i know little about science
@@APBT3chnoM0nkeyWHAT E=MC2 FUNDAMENTALLY means is that gravity/acceleration involves what is balanced inertia. INDEED, gravity AND ELECTROMAGNETISM/energy are linked AND BALANCED opposites; AS ELECTROMAGNETISM/energy is CLEARLY AND NECESSARILY proven to be gravity (ON/IN BALANCE). Consider TIME AND time dilation ON BALANCE. This CLEARLY proves what is the fourth dimension, AND this CLEARLY solves what is the coronal heating “problem”. I have proven why the rotation of WHAT IS THE MOON matches the revolution, AS I have proven why WHAT IS THE MOON will (and does) move away very, very, very slightly in relation to WHAT IS THE EARTH/ground !!!!
By Frank Martin DiMeglio
Gravity/acceleration involves what is balanced inertia, as WHAT IS E=MC2 is taken directly from F=ma; AS the rotation of WHAT IS THE MOON matches the revolution. This is CLEARLY consistent with the FOURTH dimension AND conservation of energy, AS the stars AND PLANETS are POINTS in the night sky. (INDEED, gravity AND ELECTROMAGNETISM are linked AND BALANCED opposites.) Consider what is THE EYE ON BALANCE. What is E=MC2 is consistent with TIME AND time dilation ON BALANCE, AS ELECTROMAGNETISM/energy is CLEARLY AND NECESSARILY proven to be gravity (ON/IN BALANCE); AS TIME is NECESSARILY possible/potential AND actual ON/IN BALANCE; AS E=MC2 is taken directly from F=ma; AS the stars AND PLANETS are POINTS in the night sky ON BALANCE; AS c squared CLEARLY does represent a dimension of SPACE (ON BALANCE); AS the rotation of WHAT IS THE MOON matches the revolution. Great. MOREOVER, WHAT IS THE MOON will (and does) move away very, very, very slightly IN RELATION TO what is THE EARTH/ground. Great. I have FUNDAMENTALLY and truly explained the cosmological redshift AND WHAT IS THE FOURTH dimension. (Consider WHAT IS complete combustion AND WHAT IS E=MC2.) GREAT. Again, gravity/acceleration involves what is balanced inertia; AS WHAT IS E=MC2 is taken directly from F=ma; AS I have FUNDAMENTALLY and truly explained the motion of what is THE MOON; AS ELECTROMAGNETISM/energy is CLEARLY (AND NECESSARILY) proven to be gravity (ON/IN BALANCE). Great !!!! Again, consider TIME AND time dilation ON BALANCE. Perfect. Think. Again, I have CLEARLY proven WHAT IS the FOURTH dimension ON BALANCE. “Mass”/ENERGY is CLEARLY electromagnetic/gravitational ON/IN BALANCE. GREAT !!!!
By Frank Martin DiMeglio
The beauty of Arvin Ash's video is that after watching it for just a few minutes, I immerse myself in the experience, likening myself to a subatomic particle, and attempt to truly grasp what Arvin is conveying, and that's why it takes a couple of hours to watch the full video.
yess!
The explanations in this video as to why there are exactly 3 spatial dimensions and one time dimension in space/time seems to provide an argument against string theory, which requires either 11 or 26 spatial dimensions depending on symmetry considerations.
String theory theorizes dimensions that are small and curled up inside the large 3 spatial dimensions. Such dimensions could exist, but 4 or more large spatial dimensions are essentially ruled out.
If these small “extra” dimensions are curled up to smaller than the Planck length, can we ever perceive them, or are they just a mathematical construct (convenience) to allow string theory to “work”?
This is why I want to have a joint PhD in Cognitive Neuroscience and Theoretical Physics. Goodness, I adore Physics! Much love! ❤️
That is when your girlfriend says she needs some space and time to think about things.
No, this is when your girlfriend is trying to get rid of you in a nice way.
😂
Scientists now believe that empty space is actually filled with Quantum or Vacuum Fluctuations. _"Vacuum fluctuations appear as virtual (i.e. non-material) particles, which are always created in particle-antiparticle pairs. Since they are created spontaneously without a source of energy, vacuum fluctuations and virtual particles are said to violate the conservation of energy. This is theoretically allowable because the particles annihilate each other within a time limit determined by the uncertainty principle so _*_they are not directly observable._*_ "_ (Source: Wikipedia) Despite its name, Virtual “Particles" are *immaterial.*
As a ML engineer who works with multidimensional tensors all the time , this felt surprisingly easy
Thank you for your clear and simplified version of this topic!
Eagerly awaiting for your the simplest explanations for very difficult problems.❤
Wow! Brilliant thanks. Been looking to get the Minkowski graph explained in the sense of shortest/longest distance concept and the C indicator in the vertical time coordinate. Your graphs are excellent as are your explanations. Hard to find teacherswho can word these kind ocomplexities properly.
Really, I have never seen/heard an explanation less clear and comprehensible than this.
I am no novice of the subject and I always click on videos that look like it could help me understand a bit more: this was a mistake as I am a little bit confused now. I have to go elsewhere to get some understanding back.
The key is understanding 4:40 and 6:40. In space, the *shortest* route is a straight line. In time, the *quickest* route is anything but a straight line, BECAUSE, moving slows down time relative to the traveler themself. It's only misleading if you're assuming slow velocities like walking (it's mathematically still true, just a negligible difference), or more apparently, that the traveler in greater motion meets the non-moving traveler at a later time. They both meet at the same exact time, but one took a longer path through space, and motion through space slows time for that person relative to a stationary observer. The closer you are to the speed of light, the slower time passes for you, relative to a stationary observer. Light itself experiences no time, because it travels at the fastest possible velocity in the universe. This is special relativity. General relativity on the other hand paints the opposite scenario, depicting the slowest possible velocity in the universe. When falling into a blackhole, the dimensions of time and space flip. Instead of 3 dimensions of space, there is only 1, because no matter how fast you're going in any "direction" you'll always end up falling into the singularity of the black hole. It is physically the only location in 3 dimensional space you can head towards, and there's nothing you can do to stop it, which is synonymous with 1 dimensional time. AKA, the future.
@@RedNomsterSo time is slower the closer you are to the speed of light - what if you’re moving away from each other at the speed of light, would time appear stopped from each person’s perspective when looking back at the other person?
But then if you’re travelling towards each other at the speed of light you would collide at twice the speed of light, so speed is relative as well? And because you need light to see, it would be like someone killed you in your past?🧐😅
@@steveco1800 moving at light speed would require you to be massless. Like a photon (light), if you reach lightspeed, you wouldn't see anything, because you would have 0 time to experience during your travels.
But, if you're traveling very near the speed of light, according to special relativity, you experience light like ever before. Meaning a person in a car traveling near the speed of light would actually see their headlights shine and illuminate what's in front of them like ever before. Light is the same for all observers, stationary or not. It seems unintuitive, but it's experimentally proven!
It would look different, though. As you're traveling near light speed, light coming in your direction, aka the universe and objects you see would be blue shifted. The same way cosmic expansion causes redshift by expanding the space and thereby light waves traveling in space, light waves from behind you would be redshifted. It's called the doppler affect, and is the same as sirens 🚨 sounding louder as they approach, but quieter after they pass you, even if they're the same distance from you at both moments.
Faster than light speeds is when you start seeing yourself in the past and such! But that's a theoretically impossible velocity through space.
@@steveco1800It doesn't matter rather you're traveling toward, or away from something, or somebody in regards to how time passes. But it matters how much activity is spent within your travel in time.
It would interesting to understand the notion of spacetime from a LQG perspective or a quantized fields approach, for example the notion of "points in spacetime" would be replaced by what? Traditional Minkowsky spacetime would have any meaning at all in LQG? Or it would it be replaced by a spinfoam where the traditional notion of points in space would cease to have any meaning at all?
What a brilliant video!!! you answered some of my most fundamental questions. Thank you.
I literally have a “Space-Time” playlist … I think I’ll put this on it 😊💜💫
General relativity and quantum mechanics will never be combined until we realize that they take place at different moments in time. Because causality has a speed limit (c) every point in space where you observe it from will be the closest to the present moment. When we look out into the universe, we see the past which is made of particles (GR). When we try to look at smaller and smaller sizes and distances, we are actually looking closer and closer to the present moment (QM). The wave property of particles appears when we start looking into the future of that particle. It is a probability wave because the future is probabilistic. Wave function collapse happens when we bring a particle into the present/past. GR is making measurements in the predictable past. QM is trying to make measurements of the probabilistic future.
I don't understand your second sentence, can you please elaborate?
Whats stopping you using GR to make measurements of the probabilistic future?... Nothing, your statement is wrong. I feel like you're getting hung up on the time aspect when the forces involved are at different magnitudes of strength. A tiny magnet can overcome the gravity of earth etc
A "predictable past" is an oxymoron. Maybe you mean the "observable" past? There is no such thing as "the present moment" because your present is not my present. The differences may be imperceptible but they are nevertheless measurable. Every observer has a unique world-line because of "locality" (two particles may not occupy the same space at the same time). Quantum observations are never "instantaneous" but are measurements of things that already happened.
Time and Space are an illusion humans are wasting their time by studying the observable universe,,the thing is that we cannot imagine and define things that are out of this world similar to computer AI whatever data you give to computer ,it only play and give information within that limit ,computer can give you new insight but within the range of data we provided but can not generate new ideas beyond the scope of data provided ,similarly this world is our box(data) we are only creating new information by combining the information that are within this world ,,we can not define and explain things that we have not seen before.
Time dilation IS the detection of an addition spatial dimension. Here is a great video about it: Chapter 1-4: Rethinking General Relativity as 5 Dimensions of Physics - A Unifying Theory of Gravity
If spacetime can expand and contact, the forces contained in it could also be larger or smaller. Perhaps explaining dark matter and energy
Space time is space and time space is needed for anything to play out within time and time is needed for anything to play out within space. That why there the same thing know as space time. Space never ends but everything that makes up the universe does and the expansion of space is not expanding but is already there and matter is expanding within it.
When we speak of _space curviture_ it seems to me that this implies higher dimensionalty. That is, how can you curve something if you don't have at least one extra dimension to curve it in? One of the seminal books I grew up with was Flatland. Which explored a people constrained to a 2D plane. That plane may very well be curved, but the Flatlanders would never know it. But we, from our 3D perspective, could plainly see that.
A space can be curve, meaning it may have curvature properties, without requiring the existence of further dimensions. However, it may eventually be simpler to describe it if one does consider further dimensions. I mean, what's so special about orthogonal straight lines but their simplicity of use by our minds?
The issue is that the concepts we use to describe reality should not be confused with reality itself. In that sense, Earth may very well be the center of the Universe, it's a possible but highly inconvenient description that would only go against the Occam's Razor Principle.
@@Pedro_MVS_Limawhat a well thought out response. Thank you.
The more and more i see people like you i wonder why can't i explain things like these people.This is how education should be! Everyone should be able to visualize and have curuosity to ehy that happens.You re one great tutor❤
You want your education system to be based on deceptions and BS? Physics already had a canvas to use as a framework it was just 3d space and also time, but now they have invented an impossibility spacetime, and its messed up rational physics. This is of course, on purpose.
I've been having to make various appointments recently, and the point is when you make an appointment, you need four pieces of information: the cross streets, the floor number and the time. So, they must be part of the same thing.
lol the variables of an event, excellent.
I am so impressed my the way you explained that i hit like button and subscribed spontaneously. Hats off to you sir. You are by far better than many as i keep watching such content.
From Pakistan
I've been wondering if divisional algebras which work only in 1, 2, 4, and 8 dimensions has something to do with space time. Also I read something, not sure where, that in hyperbolic geometry that what might be time dimensions have to be smaller in number than space dimensions, that the smallest number of dimensions which works is 4 dimensions. And perhaps why space-time is 3 dimensions of space and 1 dimension of time. Now that might be just the geometry of space-time. But does that still tell us what space-time IS? What it's made out of?
there is NON-EUCLIDIAN GEOMETRY math which answers alot of your questions, also N-DIMENSIONAL GEOMETRY both are upper division class math 700s
Before watching this video, I thought we need to consider the velocity of the object along with time and distance. So we need time as fourth dimension. But now I clearly understood how it is related and used. Thank you.
Thank you very much for your professional insight and helpful advice.
I like that you point out that 'time' on the surface of earth is slower compared to an identical clock in unaccelerated space.
However, gravity doesnt 'curve' spacetime, it pinches it in to the core of the gravity well (the earth in this case). Any 'curves' or orbits have to do with the other object's speed relative to the earth's gravity well.
Light gets bent very little as it races by our dimple of a gravity well. As a contrast, a person standing on the surface has their curved spaacetime starting at the top of their head, out their feet and running straight to the core. Our way there is blocked and that's why we feel 'weight'
The way to the center of the core is blocked because matter under acceleration stratifies by density with the heavy dense stuff at the bottom and the light atmosspheric gasses at the top.
What would have been a nice touch in the video would be to further the explanation that time is fastest in unaccelerated spacetime, it's slower on the surface of the earth with our meager 9.8m/s2 acceleration and it is most definitely slowest at the core.
assumptions of Newtonian weightlessness at the core are not considering this reality. The densest elements migrate to the core, while gasses go up. Acceleration is greatest at the core and time is slowest.
Really great video! There were moments where I felt like I might actually be able to understand some of iat a novice level. Maybe watch a 10 or 20 more times. Not being cheeky here… I’ve been banging my head against this wall for years, just a really hard concept to a simile. May just have to check out that brilliant course.
you can do it!
Wave particle duality. Wave in space, particle in time. The uncertainty principle. Position in space, momentum in time. Or is it the other way around? The amplitude of a quantum wave function is a complex number. Which is the imaginary part? Space or time and when?
Nicely put, although it should be mentioned that c equivales to the speed of massless particles, not especially photons. If would happen that photons have mass, then their speed wouldn't be c.
I do wonder a little about the extra time dimensions sometimes. It seems permissable for string theorists to posit extra spatial dimensions that loop back on themselves on small scales. So why not posit extra time dimensions on very small and/or fast scales? anti particles already kinda look like they go back in time from a certain perspective. I know there is so much I'm missing in this conjecture but would appreciate what avenues to go down to understand why it wouldn't be feasible.
They probably exist on a quantum level, based on string theory. As mentioned in this video, they might be unstable on a large scale. Thus higher dimensional life forms might exist on a quantum level based on particles we haven't discovered yet. Those life forms may not exist as how we know it, they might have a different concept of existence that we yet do not understand
@@GokulRaamthelegend I wouldn't go as far as life forms. All of our current understanding of life necessitates macroscopic structures well beyond the remit of QM.
Having two time-like coordinates will make it so that energy is no longer conserved, and you will never be able to get two things to stand still (be at rest) with respect to each other. There are at least two string theories with multiple time-like dimensions, and they predict things like protons decaying into heavier neutrons and stuff. Also atoms can't form, because you can't get protons and neutrons to stick together (stand still with respect to each other).
@@juliavixen176 we already know from GR energy isn't strictly conserved. E.g. redshift photons. I mean it's still conserved as far as time translation symmetry is upheld, by Noether's theorem, but GR breaks that symmetry routinely.
Also AFAIK zero-point energy of the vacuum is still an unsolved problem and potentially linked to the negative pressure required for the spacetime expansions we currently observe.
@@juliavixen176
I mention zero point energy in response to your statement about not being to get two things to stand still w.r.t each other. As in by Heisenberg uncertainty we can't get things to stand still period! And the energy associated with this is somewhat poorly understood atm and leaves room for zany theories such as extra time dimensions. Well I guess people that know more than me can rule it out, but I'd like to be pointed to resources that tell me why.
also sorry for the somewhat unclear initial reply, I'm responding on my phone and the app doesn't let me see your comment as I reply
1. Time is a concept only
(i.e. what enables us to think efficiently and collectively about
the relative movement of any number of objects).
2. An object is at rest relative to it's self
(unless it's being squashed in e.g. centrifuge or rocket).
3. Acceleration and gravity are strongly related but
gravitational acceleration (of falling object) affects every particle equally
whereas
centrifuge or rocket acceleration tends to squash an object.
4. The twin returned from a relativistic space journey
would be the same age as the twin who stayed home
if the home twin had been kept in a freezer down near absolute zero
for some fraction of the duration of the space faring twin's journey.
What does the fact that the reunited twins would be
the same age (i.e. in the same biological condition
(assuming technology capable of freezing/thawing bodies without damage))
tell us about
what's *going on* in the body of the space faring twin on his journey?
Perhaps the total amount of movement of his particles,
relative to his other particles,
is simply less and
this because particles have a limited amount of
movement possible for them and
some of that movement is 'busy' in the direction of flight?
Another gorgeous and informative video, Arvin, thank you! It is my understanding that the vector cross product, which is key to maxwell's equations, does not work in 4 or more spatial dimensions. No one ever seems to bring this up as an explanation for why we experience 3 dimensions. It's this a valid argument as to why, or is there an out for higher dimensions for electromagnetism?
there are 3 and only 3 spatial dimensions, time is not a spatial dimension, "spacetime" is nonsense.
@@axeman2638 "Spacetime" does not imply that time is a spatial dimension. In fact it explicitly states otherwise, as they have opposite signs in the equations. You can kind of interpret that as stating time is an "imaginary" spatial dimension, but its certainly not stating that "time is a spatial dimension" in any meaningful way. It might behoove you to try understanding concepts before arbitrarily calling them nonsense.
> No one ever seems to bring this up as an explanation for why we experience 3 dimensions
Because we don't control the universe. If the universe had chosen to give us 4 spatial dimensions, certainly Maxwell's equations would be meaningless. But intelligent beings in such a universe would simply come up with some other equations that describe their own forces (electromagnetism as we understand it wouldn't exist, but some other force that follows 4D-enabled rules would exist in its place).
Of course that's all speculative philosophy. The universe does have three dimensions and our equations do work, so its little more than a thought experiment to imagine higher dimension universes. But the first step to such an exercise is realizing that _everything_ we know would be different - the particles, the forces, and the math we use to describe them. Everything The ones we know of in our 3+1 universe all explicitly require a 3+1 universe and wouldn't work in any other universe. But some other completely different particles and forces (and math) might.
People have of course tried to formulate such things, with middling success. There's a general thought that its not possible because we can't make the math work but that in itself is exactly the problem I'm pointing out - just because _we_ can't do it doesn't mean the universe couldn't have. But its very hard for us to separate the idea of a universe that can't exist (based on the fact that it doesn't) from a universe that "can't" exist (based us fallible humans being unable to figure out how to make our equally human mathematics work for it).
@altrag yeah you can stick your condescending smug face where the sun don't shine mate. I know the official story pretty well thanks, perhaps even better than you, it's rubbish, Space does not warp, it has no substance or properties, it's no more or less than the distance between things, it's flat and euclidean. Einstein is bunk.
Equations are not reality.
I'd like to point out that Modelling Causality as a Poisson Process (events on a time line w/ exponentially distributed inter arrival times) we are transforming from the Bayesian into an exponential form of causality (np=t*lambda), e^mean*variance and plotting 'open point' on the timeline allows for a least Paths solution to A QM Model of Causality I refer to as the 'Temple Model of the QM of Causality'. The open point on the timeline represents the 'Temple' State Space Model itself. It allows the 'user' to apply the same exponential transform to the 'other parts' of the model. We can manipulate causality even w/ a pair of dice.
The (very simplistic) way I look at spacetime is that space is a computer monitor and time is the ‘refresh’ key which allows more than one thing to happen in any given point on that monitor. Imagine how much bigger the monitor would need to be if we needed a new section of it for each new window we open.
The way I visulise it (if comparing to a computer) is, 1 plank time unit = 1 CPU cycle.
simulation argument is getting waaay strong.
@@Jake-rj4dx simulation argument is really an escape clause for those that dont believe in god. Basically confirming that a superior being has created this idealistic program / universe / reality.
I just stumbled upon your channel and I am blown away by your relatively indepth review
Your Minkowski graph of the math of spacetime is a powerful teaching tool. I wonder if space or time can exist at all without each other. If there was no time, how could a place exist? If there was no place, would time have meaning? Are time and space inseparable? 🕳
I always thought about that. I came to the conclusion that no, they can't be separated, but at the same time, space is more important and central than Time. Time is a consequence of energy. To reach that conclusion, I used my naked imagination: Imagine you have a superpower: you can freeze everything to the quantum level. Now I want you to freeze this universe completely, until no electron can move, no virtual particle pops up in the quantum field forever. In this scenario, you'd still have space, wouldn't you? With your mind's eye, you can still see the oceans and forest and planets completely static. But time would be gone because it would literally never be capable of passing. Now, try to begin to imagine anything to conceptualize time without space. You can't even begin. You can't even think or imagine a superpower or anything. A vaccum? That's would be a space. A true vacuum? That would be space again. A black universe devoid of anything? Still a location in the grand scheme of things. So space is the basis and time is the property.
@byamboy It's this type of reasoning that makes me think Roger Penrose's idea of a cyclic universe is the most likely theory (ofc my opinion means little lol.)
When true heat death finally happens and all the blackholes evaporate, time will be meaningless. No how matter how unlikely something is, any possibility of it happening will mean it will eventually happen. Even if takes 100^1000^100000 years to happen.
Well you can think of them separately, as you can think about x or y direction in space. Space without time dimension would be just a frozen moment of the universe. Time without space would be a blank and EXTREMALY boring existence with nothing to see or touch or experience.
La elementalidad de las ideas de tiempo y espacio, nos impide o dificulta hablar de ellos. No se pueden definir sin caer en redundancias o círculos viciosos. Así, el tiempo es el intervalo que transcurre entre dos eventos. Espacio es el ámbito que habitamos. Propongo un nuevo término designar tres cosas fundamentales, que no tienen definición, es el término EXTENSIÓN, para esas tres magnitudes fundamentales, o magnitudes dimensionales fundamentales, ya que de la EXTENSIÓN, se derivan, el espacio, el tiempo y la masa. Que son tres cosas extensas. Porque pueden existir en el Universo y podemos referirnos a ellas como existentes. Porque los podemos estudiar porque muestran propiedades diferenciables, de una con respecto de las otras. Porque las podemos medir usando instrumentos diferentes. Porque acceden, de alguna manera a ser percibidas. Porque podemos cuantificarlas y los cálculos.que hacemos son congruentes. Pero que nos intrigan cuando tratamos de verlas individualmente; es decir, darles calidad absoluta de existencia. Porque, aunque no se haya dicho, la masa también es relativa al espacio y al tiempo, ya que incrementa con la velocidad o energía cinética. Incluso, se origina de la velocidad misma, se genera a partir de bosones que corren a la velocidad de la luz. Entonces la EXTENSIÓN, puede asumir el papel arquetípico o primordial, con respecto de esas tres modalidades de entes diferenciados pero relativísticamente asociados.
@@byamboy I can easily imagine a black universe devoided of anything, but I can still suspect there is some kind of time, since even this dark universe devoid of nothing, is something. So Space is the bases and time follows as a property.
Information is everything they say and some say everything is information, the foundation of reality. Space contains all the information and time is reading it.
"Space time" is what an astronaut exclaims when he's suiting up for a space walk.
groan... i really wish i hadnt read this lol
spacewalks are recorded by professional divers in the NBL.
The truth is they are more like waterwalks vs outer spacewalks but where is the magic in that!?!
The space is in time time is in space they all are connected in operate together
E = experienced time 😉
Your analogy is revealing: we do have Space and Time because we built equipment, to define Lab frames (Buildings, roads etc.) and clocks to define Time (synced with satellites etc.) , allowing to fit a Mathematical Model (R3xR), which needed "stretching time" and compress distance (Lorentz transformations) and adjustment in the presence of the real, Natural "frames": matter (GR). After 70s we started understanding it is a Network (Quantum Computing); it became apparent it is Adaptive (QFT interactions, Chemistry etc.). But Classical Physics still needs it (S-T). Otherwise the building "pixel of Universe", the leggo block for the Universe, is the Hydrogen atom: 3-quark directions (RGB) to define local Space and a spectrum of frequencies, as a metronome to keep the beat (Pythagoras would have liked this). (see Yewbzee too :). Now, due to Gauge Theory, we understand how 3D-Space and Time emerge, and "look as if related" (2x2=3+1: SU(2) "thing").
Arvin, Magnetars would be very interesting topic to explore. BTW very nice work in this one. 👍
Here's why there can't be more than one dimension of time: when we talk about time we're actually talking about the 'rate at which causality happens'. And causality is ultimately a "spatial" phenomenon: it's the rate at which events can happen in space - for objects to move and interact in space. So really it doesn't make any sense to think of time as separate from space. Spacetime is the only thing that makes sense. Spacetime is space + causality.
Can you please make a video about the leading theories of what there was before the big bang? If there are any notable ones, that is
MgT: Yes, Please!!
As time began with the Big Bang, what's the meaning of "before" in that question?
11:40 If I travel in the past and kill my father, then he would not be alive to meet my mother. So now I am never born to go back into the past and kill my father which means now my father lives and does too meet my mother. My mother then goes on to give birth to me, so I grow up and travel the past again and kill my father again. Now I am never born again and I do not go back to kill my father again. So now my father lived again and meets my mother again. Now Ill be born again and the cycle repeats itself forever. This causal paradox is possible, it just means I will forever be stuck in this time loop. Every time I kill my father, the very next moment in my future is me being born again.
time is movement, which is the simplest way to put it
Motion doesn't create time. Only clocks create time. ;-)
@@schmetterling4477 im not talking about clock time. clock time is just based on earths rotation. it is meaningless in space
@@noidontthinksolol There is nothing else than clock time. The rotation of Earth alone doesn't create time. Time requires the communication of the state of the clock to an external system, i.e. an energy transfer. In case of a rotating planet that's a very, very small loss of energy, which makes rotating planets reasonably good clocks.
I've always wondered why no-one considers the steady state idea for time loops (like analog computers), rather than assuming a paradox would occur.
Space and time are indeed relative, the more time I spend with my relatives, the more space I need
😂😂😂
xD
This joke is just old and over done.
@@ChopperChad time for a new one?
I know Chris "The Brain" said in his video on space time, "Chapter 5: What is Time? Special Relativity, Inertia, Wormholes, Anti-Gravity, Time Travel, and FTL" That the relationship between space and time were contridicular, and that there is an absolute zero velocity that we should build a unit to find.
Clocks running slow doesn't mean time is different. There is only one 'now'. Calculating a difference your clock shows doesn't show anything about time.
There cannot be “only one now” if the twin experiment has them both subjectively experience time the same yet one ages significantly faster.
@@magicmulder clocks and systems ticking ay different rates only require one now. Even on earth clocks in various places drift from one another
There is no such thing as "one now" -- the "one now" that someone on Pluto describes would be different than the "one now" you describe because Pluto is moving faster than earth. When you say, my now is "now" - what does that even mean, because there is no way for you to communicate in the very instant that you say the word "now." Even when you are talking to a person across the room, the "nows" are different for the two individuals because it takes a small amount of time for you to see the light reflecting off of them. This does not make any practical difference because the time difference is so small that you do not notice it. But on cosmological scales, this communication speed limit makes a difference in what you can possibly describe as a "now."
@@ArvinAsh Just because you can't perceive every point in space at the same moment doesn't mean it's not currently experiencing the same now as a current observer - heck you don't even get to see 'now' since it takes time to propagate through neurons...
At some point in the future you will observe its state that occurred at the time in the past that it experienced the same now as you (again not that you would see that) There's no evidence to support that there is any more than the current instant happening in the universe - observation of that is of course limited by propagation delays of that information. There's certainly nothing that has already happened tomorrow or at any time after 'now'... everything that is perceived is from a time in the past from any observers point of view, but that again doesn't mean it hasn't already had many more interactions already between the time you see it at, and the time it is at when you are seeing it.
It's actually observable... light travels about 1 foot in 1 nano second. Computer clocks tick at 1Ghz+... 1Ghz is 1 cycle per nano second... so every N feet of distance is also N nanoseconds in the past from your point of view... When dealing with a hardware device in the 90's I got to learn just how long a nanosecond is... putting the card on 6 inch extender on an ISA bus delays the signal about a nanosecond (since electric signals really only go about half the speed of light maybe more, i've seen more recent approximations that it's 70-80% of the speed of light, but given the amount of capacitance a signal has to fill before a signal can actually be detected 50% is good enough; that short distance started causing it to fail on certain motherboards. But certainly every signal that went 6 inches was perceived from a ( it's not 'now' at that point it's a past now that the signal was generated, before it is observable at a time after it was generated... but still that card is generating signals in the 'now' that will be seen later).
There's certainly no evidence that anyone is stuck in the past, any more than that events have already happened after now.
As you said, how the time and space can be the same while the units are different. At the same time you have also said that the concept of time is developed by us humans.
In my local context the time is calculated into the distance of the sun's movement in the sky and there are around several units of time within 24 hours. For example the smallest unit of time is 'badany' means a step. Jill means when the sun rises. Pari means when the sun moves up in the sky around an hour after it rises. And papan means the mid day.
In this way, the time is just the same as the distance.
Sorry, but I believe that Newton was right and Einstein is wrong. Einstein's THEORY has never definitively been proven! All you are doing is regurgitating unproven rhetoric.
Uh, dude you should review the scientific definition of “theory.”
I believe space, and time are relative to each other, but they are experienced differently by different people differently, as well as the past, present, and future are relative. They are part of the same thing but yet separate. Much like when two cars driving down a road each at variable speeds, in opposite directions... As you drive forward looking ahead you perceive another car traveling towards you. Both speeds may be exactly the same, or might be variable. You are looking at the future at that exact moment where you will be as the other driver is looking at the future where they will be. As time progresses the space between you both decrease, and you both travel closer, and closer relative to each other, and at some point you both exist in the same area of space, and time, experiencing the present even if for a very quick moment in time. As both cars go past one another, you each look into your rear view mirrors, to see each other move away at variable speeds, and now you both are looking into the past from that moment of each others present. As time progresses, space appears to expand with each car moving farther, and farther away till you do not see each other no longer. Even tho you no longer experience each others presence in your current state of perception, you still both exist, and are relative to one another. Its like the tree that fell 1000 miles away that you never perceived to have fell, and never heard. Did it truly fall.. Yes of course, since your space, and time are relative to that trees space, and time. The relative of space, and time are both experienced differently based on your perception. In the above examples, time, and space has not changed, or has it? Even tho you seen each other in three different states of existence future, present, and past, you still exist, even after not being able to see one another. It can be argued that does the same space, and time exist in the same present in two different locations of space, and time. Now if both of you were to turn your cars around, and travel back in opposite directions, your path should cross again only to repeat the above. Can it be said that the same space, and time exist, and are of the same thing.. lol. As you both travel towards, and away only to repeat going back towards each other is space expanding or contracting? Is time reversing or continuing? Does time really exist or is time made by a sense of perception. Space can change, and is in constant flux, but does time flux? Time to me is pretty much man made unit, to express ones sense of perception. For example like standing on the edge of a road with cars going by constantly in rush hour traffic.,... As you stand there you experience time on your own level of perception, where as everyone zooming by is experiencing time on their own level of perception. Time may still be relative to everyone in the exact present moment, but it fluctuates over time concurrently. Can it be then said time is the same to everyone even if experienced differently by different people. Now lets take this one step further. Its already proven that when we see it takes approx 2 seconds for the mind to process the information, but with age it takes a bit longer which is why elderly, and young people process thought, and what we see at different speeds, and are much slower or faster to react towards situations while driving differently. So if a person older perceives things slightly longer say 4 seconds where another younger person did so in 2 seconds can it be said space, and time are of the same thing. So when two people are driving of different variable ages, that process information at different speeds, do space, or time change for either of them? Yes it does...... The amount of time taken to process the information of space, on future, present, and past are at differential speeds of time by two different people. Space however remains the same and constant flux.Time is basically an illusion but it is relative to the constant flux space. For example two people as above both traveling by car but each doing something completely different, one person is smoking a cigarette while the other person is flashing the bird. Both see each other but 2 seconds apart, and differently so space, and time are not of the same thing. But are they are relative... Sorry... lol
You made this complex concept super easy & understandable 👍
Thanks for making me to understand to certain extent cause I am just medical professionals, head and neck surgeon, retired Prof, age 76 years ago. I am from Burma (Myanmar).
Thanks again.
Yours sincerely Dr KMA ENT
The way they function they all do it together and using it in a method through dimensions geometry time and light
No one can make me understand, or believe to understand, complex physics like Arvin.
Very nice explanation using the speed of light, time and distance equation to show space time.
Time Dilation effect: gravity effect is weaker than speed effect. Could that be related to gravity being the much weaker force compared to the weak nuclear force and the strong nuclear force, which is where photons and speed of light come from? The forces are different, so their effect will be different.
Is that why gravity has a weaker effect on time than speed has on time
Looks like all the things are directly related: forces, time, distance, mass, energy.
Gravity is not a force. It's a measurement. It's like saying temperature is a force. Non-static measurements are measurements of acceleration/motion.
The law for determining the amount of force in the system is Newton's Law of Motion F=ma.
Mass is static. It's length, width, height, volume. Acceleration is what gives mass force. Gravity is the measurement of the force being applied to accelerate the mass in space. Temperature is the amount of acceleration the mass has in time. For time, you can use E=mc. Atomic energy converts to radiant energy with acceleration.
When an atom gets to c, it becomes a photon. It still has mass, radiant mass that is, in the form of length. The photon's wavelength is its mass factor. (c) is the speed of light and E or F is the Force factor. As the photon's wavelength increases, it's force factor decreases since force decreases with distance (longer wavelength).
@@stewiesaidthat if gravity is not a force then why is it measured as F = ma, where you can measure gravity as mass x acceleration due to g (gravity)?
I see that Einstein spent 10 years struggling with whether gravity is a force or not, and eventually said it's a result of the effect of 2 body's mass acting upon each other and the amount of space-time they curved. Something like that.
It's taught in school as a force. In every day life it's treated as a force. Where do you use it not as a force but as a curvature of space-time?
@@Google_Does_Evil_Now Gravity and Temperature are measurements of acceleration. Gravity is the measurement of how much force is being applied to accelerate the mass in space while Temperature is the measurement of how much acceleration the mass has in Time.
F=ma/E=mc. Acceleration in Space/Acceleration in Time. Mass is just stored energy so F=a/E=c or Force equals Acceleration/Energy equals Acceleration. The difference between Atomic energy and radiant energy is its Acceleration factor.
Everything in the universe is then defined by its Acceleration factor. Which means the Proper frame of reference is the acceleration factor.
The earth spinning on its axis, the frame of reference is the zero acceleration factor or its axis. Because the earth is spinning, it's mass is being accelerated not only outward but also forward causing curved space. As the radius from the center increases, so does the acceleration factor. F=ma. Since the Force (Earth's rotational speed) remains the same, the mass the must decrease in value. This can be observed by the thinning atmosphere with an increase in altitude. The Earth's mass is not being pulled inward but accelerated outward.
This has been verified with synchronized clock experiments showing that as the radius increases, so does the acceleration factor. The earth rotating on its axis creates curved space.
If mass does no create Acceleration, then what does?
If you go back to the big bang, you will see that its an acceleration event. Current theory says its both space and time but logic dictates that it was a Time event. The point that un-accelerated energy transitioned to an accelerated state. Energy can be neither created nor destroyed, only transformed. That means space always was and that the current state of energy (accelerated) was in a different state.
What causes planets to orbit stars, stars to orbit black holes, galaxies to move through space? The logical explanation is an energy imbalance. The same energy imbalance that creates hurricanes, tornadoes, typhoons. Space is an ocean of energy. Planets and stars are just clumps of that energy that became attracted by electromagnetism.
The laws of physics are the same for all frames of reference. As QM has shown, packets of energy react to differences in electromagnetism. Electromagnetism is the attractive force. Gravity is the result of an object being accelerated on space. An object that accelerates itself does not experience gravity as there is no outside force acting upon it. This was shown by the hammer&feather drop tests. The mass of each object had no influence on the acceleration factor. The object in the air has a +5 acceleration factor than what the ground has. When the hammer is released, it is no longer being accelerated at the +5 Frame of Reference. Since an object in motion stays in motion unless acted upon by an outside force, the ground (moving through curved space) is following behind and Impacts the hammer. The same as when an object falls off the back of the truck and hits the trailing vehicle.
Newton was right about the apple falling being a difference in Acceleration factors. What he didn't understand is why. The mass of the earth doesn't curve space, the motion of the earth (spinning on its axis) is what creates curved space. This is something Einstein never understand. If you listen to Sean Carroll's podcast on Einstein, you will see that Einstein didn't really understand physics. His biography is littered with examples of plagiarism. He stole other people's ideas, had no clue how they worked, and cobbled together his Spacetime fantasy universe using relativity as the basis for his physics.
If you check, using acceleration as the proper frame of reference, you will see that relativity is 180 degrees from reality.
Kindly let me know the answer for the following HYPOTHESIS please.
SCENARIO
1. Only INDIA EXISTS as ISLAND.
2. Other countries are submerged
How Is it feasible to have
1. ONLY SPRING season
2. 24X7 Sunlight
in INDIA for 2500 years ?
This video was very informative and explained so well. Thanks for sharing
Yes, I like to hear about some universe stuff. This is good because it teaches from the beginning.
Spacetime is 4D (3D + TD) array of tensors. [x, y, x; t]. A framebuffer. A movie file (like .AVI) is a very simple example of 2D + TD "spacetime".
"If it was anything else, the universe would be unstable!"
That's such a silly argument. Certainly if it was anything else the universe would not function as we know it with things like inverse square laws. But that doesn't mean there wouldn't be some other type of universe that wouldn't work. It would just need different forces that coupled in different ways. Would certainly be unfathomably different from what we know but that's not really relevant as we wouldn't exist in such a universe to begin with.
A more interesting argument (IMO) is "this is the simplest possible configuration", as the universe generally seems to prefer simple structure over complex at the most fundamental level.
There is good justification for 2 dimensions of space not being "enough" - things would have a hard time moving passed each other (and in a 1D space it would be impossible) while 3D gives lots of space to move around in well.. space.
A 4D space would work (in some manner) if forces dropped off with an inverse cube law rather than an inverse square law (and 5D with an inverse quartic law and so on). But those extra dimensions aren't "needed" in order for objects to move freely in the same way that the third dimension improves over the second.
That's all more philosophy than science of course. We have no way to really know why the universe is the way it is. Its all just made-up justifications to satisfy whatever we want to believe. In my case, I don't feel comfortable telling the universe what it can or cannot do. It can do whatever the hell it wants and our only role is to try and understand it after the fact. The argument that the inverse square law would fail in >3 dimensions for example is subtly demanding that the universe "must" use an inverse square law, but there's just as little justification for that demand as there is for directly demanding that it "must" have 3 spatial dimensions. Physically a meaningless distinction (the universe does indeed have 3 spatial dimensions and an inverse square law) but philosophically problematic - again, IMO.
Space and time don’t exist in themselves, but represent the relationships between all that exists in the universe. So it makes sense that they would be connected in some way.
0:20 Spacetime is not just a background. It's not a matter of having painting colors with no canvas, it's really about recognizing that colors and canvas are really the same thing, and neither can exist without the other.
At the largest scales, matter tells spacetime how to bend and deform. At the quantum scale, wrinkles in the fabric are what makes matter emerge. Together, the two theories complete the circle, which is the fundamental reason why unification efforts have failed thus far. There's nothing to unify. The two theories are different ways to look at the underlying reality. If we want to understand black holes better, we need to understand what exactly quantum mechanics is telling us, and not just "shut up and calculate". We desperately need an onthological basis for quantum mechanics, just like we have one for GR.
well that the fools version of the nonsense called spacetime.
While it's simple to just say "large dimensions" to exclude the compact dimensions of things like string theory, it really raises the question of how spatial dimensions can come in a variety of "sizes".
Easily; they are distinct parts of one and the same concept (in reality). 'Space' is simply the distance between two material objects (what fills that space is another matter). And 'Time' is a particular measurement of these two objects across that space, i.e. generally in so far as they pass each other, or specifically in their mode passing, e.g. trajectory (one may have an oblique course) and distortion (the other may have a turbulent passage). The concept remains the same, but the description differs .. including any wibbles and wobbles as part of the whole, they are the special bits of the specific account.
Yey!
It's the speed of light in *vacuum* that is believed to be the universal constant and maximum speed of information.
13:20 it's not that we happen to live in precisely such universe, but life could have formed in only these 3,1 space time dimension universe only, so if life exists then universe has to be 3,1. Otherwise there would be no life to perceive it. Therefore no life form has ever perceived any universe other than 3space 1 time dimentional universe.
It's like "odds of being born is astronomically low, but yet everyone who exists has beat it"
That's essentially a version of the anthropic principle. I'd add, in addition, that life AS WE KNOW IT could only exist in 3,1 because life AS WE KNOW IT evolved through chemical chance within this universe - there's no reason to think that life couldn't, theoretically, come to exist in a 4,1 or even idk a 7,4 universe, it just would not resemble our life at all!
@@MaeveFirstborn yes, true. Universe with different physical laws can sustain life with different biologies. Maybe our own universe can sustain different kind of biological evolution about which we might not aware of.
I view time in 3 dimensions as well, but each point represents a single energetic state of the entire 3D space. This means time not only goes forward and backwards, but also sideways and up/down. Sideways can represent different versions of one dimension, while up/down represent parallel realities.
What people assume as time being a single 4th dimension of space is only because of the assumption that there is only 1 real timeline, what one experiences within space. This is why formulas based on a single variable "time" works because the formulas only apply to a single linear point of spacetime. One couldn't easily validate the results outside of this one experienced timeline. But that is an assumption. What people call "string theory" can be encapsulated by the idea of a 2-dimensional representation of time, but it ignores the alternative version concept of each individual timeline as the 3rd dimension of time (the choices not taken by one version, is taken by an alternative version of the same reality).
When space "bends" time, all that means is that the rate of change in space is a relationship to the rate of change in time, meaning the 3-dimension of time is itself encapsulated in a higher dimension of something related to time. When you accelerate in space, that means the number of units of time that changes is done quicker in the higher dimension of "experience of time" or "rate of change". From my perspective, that higher dimension above time is consciousness (it encapsulates these dimensions of awareness). The awareness of change, which is a function of time, is why the perceived change in space/time is relative. It depends on the point of view. Without different points of views, there would not be general relativity.
Unified Spacetime decomposes uniquely into 3 spatial dimensions and 1 temporal dimension for every observer. It brings up the interesting problems again of what constitutes an observer, and what constitutes an "event". Intersection of world lines? How does that work in QM? Surely not point-like. An "event" has to be extended in some sense, with dimensions in space and time. And it's hard to imagine a point-like observer. Things seem to get blurry. The way Spacetime decomposes seems to be necessarily blurry. So at some scale the three spatial dimensions are difficult to quantify, and so too for the temporal dimension.
It's one of the best videos on the subject.
Thank you for taking the time to explain spacetime but there is something that to me as a non-physicist (but a biologist with a PhD and much research experience, so a scientist) seems confusing. Someone travelling in a spaceship and coming back should have aged less than someone on earth according to your description, even though during that time the earth has been turning around itself and around the sun, as the solar system has been travelling around the galaxy, which has been travelling through space. So there is nothing constant and arguably the person on earth has had a more twisted course, possibly with all kinds of acceleration and deceleration added in as the universe is expanding and space is dilating with everything else moving in it in varying speeds in relation to other reference points. So the person on earth is perhaps travelling more and in a more twisted path and within higher gravitation fields than the person in space going in a straight line and back. Additionally, what absolute time on the Y-axis is also makes no sense. Movement on the Y-axis with reference to what? Besides, the space-time cartesian system is some kind of anti-Euclidean geometry where a kind of a reverse of the Pythagoras theorem applies. And in all this non-Euclidean weirdness, the only thing that we can rely on as being constant is the speed of light. In terms of what reference? Are two photons moving in opposite directions moving at the speed of light in relation to each other? C+C=C? That is an impossible concept.
For the first one, lets say that the man on the spaceship managed to escape the gravitational fields of the entire Solar System. While the man on Earth would have traveled around the Sun, and also around the Milky Way during that course, the man on the spaceship would need to catch up to him. He went far away, and now he needs to travel even more to catch the man on Earth. So he doesn't just "go and come back"
@@ningninglvr48 - They are both moving through space, they are both non-stationary and eventually meet up. They both travelled a lot before meeting again. It would be equally arbitrary to say the man in space is stationary and the space and galaxy and our planetary system moves around in a twisted course through the universe until we catch up with him.
If we move away from a dstant galaxy, our galaxy should be aging more slowly. But at the same time, the distant galaxy is moving away from us. So the distant galaxy ages more slowly. Can both be right?
Spacetime being one thing makes sense because it takes time to move through space. Conversely it takes space to move through time. Which is why time supposedly stops in a black hole where there are no dimensions.
The simple explanation for the formula "E^2 = t^2 - x^2" is that the factor between time and space is i (imaginary unit) times c (speed of light).
Then you can use the Euclidian distance again: (E i c)^2 = (t i c)^2 + x^2
Or we could use the Quaternion units i, j, k for the space coordinates. The square of each of the Quaternion units is -1.
In Einstein‘s paper, on special relativity and a problem with speech he states for one object there is no time or space. For two objects you can take equally like measuring rods. and measure a space between them you can then how to text of the clock and know how long it took you to lay down the rods. Space is a measurement between objects time is a measure between events. Space-time is a metric system to figure out this patient time of events
Thank you, Dr. Ash...I kind of get it now! The causality example was REALLY helpful...
Time is often conceptualized as a series of cycles, and not strictly as a linear dimension. If you think of a dimension, you're essentially referring to an averaged set of cycles. While many things in the universe might seem to operate on nearly identical cycles or "times", each has its own unique bubble of time. These bubbles might be very similar, but they are distinct. Thus, it might be misleading to label time solely as a dimension. Comparing time to numbers, it's like equating 99.9999999999 with 99.9999999998 - they're incredibly close but not the same. The best we can do is make predictions based on averages, but treating these approximations as absolute truths might be an oversight.
In the realms of science, where wonders abide,
A mystery unraveled, where two concepts collide,
Space and time, entwined in a cosmic dance,
A question that challenges our understanding's stance.
Einstein, a visionary, paved the way,
With his theory of relativity, night and day,
He showed us a truth, both profound and strange,
That space and time in nature can surely exchange.
Space, the stage where the universe unfurls,
Time, the river where existence swirls,
But how can they merge, these dimensions so vast?
A concept that leaves us in awe, steadfast.
In spacetime's fabric, they're woven as one,
A fusion of realms, where the cosmos is spun,
Gravity's influence, a force to behold,
Bends spacetime's fabric, as our tale is told.
Black holes, where this fusion is clear,
A singularity's pull, both far and near,
The bending of time and space, a cosmic ballet,
A phenomenon that leaves our minds in dismay.
So, let us embrace this intricate weave,
Where space and time together, they cleave,
In the tapestry of the cosmos, their mingling's sublime,
A profound conundrum, standing the test of time.
first time in my life really understanding space time , thank you😊
I've seen countless videos and explanations on this topic.
But I always fall back on thinking that time as a dimension is a weird way of interpreting what we see. Hear me out.
I don't think time is a dimension at all, but an emergent phenomena from "light speed" particles interacting in space. There is only space, and in space there are particles moving in a constant way (light speed, C) and interacting with each other. These interactions are what time actually is, there is no dimension to it.
The reason we see time flow differently when moving relative to something else, is because when a bunch of particles all move in the same direction, there is less particle to particle movement. Because particle speed is constant, C, it leaves less possibility for interacting movement against each other. And that lessened interaction between particles causes time to flow slower.
For example:
We have 2 pairs of particles (4 particles in total) stationary in space. Every interaction between the particles is one tick of time.
Now a pair of particles starts moving away from the other pair at 0.9 C, while the other pair stays stationary.
The moving pair now has less possibility of interacting with each other (compared to the stationary pair) because it has already "allocated" 0.9 C to moving away, and therefore not interacting as much.
When the particle pair then compare time with each other again, the moving pair will have had way less interactions and therefore time has moved much slower, but the stationary pair has had more interaction so time moved "faster" for that pair.
This is also why we consider photons to have "infinite time", because photons are just single particles moving 1 C (light speed), leaving zero room for interaction until it collides with something.