@@aidarosullivan5269 Jokes aside. As someone that knows next to nothing about being a nuclear engineer. I assume you realistically don't actually need to understand the atomic physics behind what you do, just the properties of physics at play. A civil engineer doesn't need to necessarily know the atomic properties of water to design a bridge that will be in water, just be able to understand a datasheet with the physics related properties that will impact a bridge. Things like, it will corrode metal at whatever rate if not painted and hoe much pressure it will inflict at whatever depth and whatever speed, and then be able to do the math. So, being a physicist would help to actually understand the deeper physics at play, but is it required? Maybe legally to work in a nuclear power plant? But like, actually required? I can't say I know :D
Yet this guy wants to question if the same thing is true around a blackhole.. we literally have to adjust the clocks on GPS satellites do to the speed they move at. We don't need to observe it at a blackhole as well. He isnt questioning gravity and we have no idea what causes it other than mass when everything else has a particle or wave.
you can technically get into the past relatively to a given object if you could somehow leave its time cone, but you can't interact with it, only observe its past version from the distance and key word: relatively, because our planet is inhabited by the dinosaurs for an observer that's 70m light years away or it's not even present for someone on the other side of the universe, so you could say they're several billion years in the past relatively to our planet and vice versa
light cones are defined by the speed of light, if you could observe something outside of your light cone then that'd mean that light is somehow moving faster than c, which isn't possible
So if the light emanating from earth is an ever expanding sphere in space. (moving at light speed of course) Then in order to see into the past (and/or interact with it) you would have to ascend into the 4th dimension and become what we would consider an omnipotent being. Which, from my very surface level 2 minute read of the light cone wiki, would be the only way to actually leave the light cone right?
@@ShrimpInACoffin either that or find a way to create wormholes Just moving away from any given object faster than light will make it appear to go back in time because you're outside of its present light cone But if you approach the earth at FTL speeds, the time will seem to run faster on it, so in reality you can't get to earth's past when travelling faster than light, you can only observe it Even then if you plug something like 2c speed into time dilation formula, weird things will happen because you'll move in complex time
16:55 ... A little correction regarding heavier than air flight. Within a YEAR of Lord Kelvin's infamous quote - so 1896 - Sir Lawrence Hargraves took flight from Stanwell Park Beach - just a few kilometres from me in southern Sydney, Australia - suspended from one of his boxkite designs. Wright Brothers was POWERED flight ... which is, admittedly, slightly more impressive than hanging from and oversized kite, but Australia doesn't have much historical scientific "clout". The kinda cool thing is that to this day, Hargraves' discovery is honoured by hundreds of hang-gliders and paragliders, etc. taking flight each day (coditions permitting) from the hill above the beach.
like enough order to create the proper conditions required to sustain life? was just watching interstellar and your comment made me think about the scene when they were deciding between edmund's and mann's planet to land on and they discussed how the black hole didnt allow enough events to happen which means a lower chance of the planet being habitable.
@@julius7949yes, entropy can decrease in a system as long as that system is not isolated. Meaning you can have negative entropy as long as entropy increases elsewhere.
I have the same problem with tachyons as I do hawking radiation. The math checks out for both, but there has been zero experimental evidence for either one.
@@Shoomer1988 I agree, black holes are the same way. But we now have direct observations of black holes confirming their existence. Just because something exists on paper doesn't mean it exists in reality. Observations are needed.
I like your line of thought! It isn't _quite_ true, though. The reality is more complicated than either of those simplified concepts. The idea that light is slower in media other than vacuum because it bounces around and takes indirect paths is pretty neatly countered by the fact that transparent materials exist. If that was the reason, then those bounces would be in random directions. Everything would do full random scattering, like paper, and we'd have no windows or mirrors. Depending on how you interpret the concept, no color, either. Clearly we have mirrors and windows _and_ color, so something else is going on. 🤔 And yet, nor does "a photon" actually "slow down" in a medium with a high refractive index. You'll never see that happen, can never measure it to be the case, no matter how much technology you get access too, because it isn't actually happening at all. But... underlying that is the fairly mind-blowing fact that "a photon" isn't _really_ a valid concept in and of itself. At least, not if you think of it as "an object", which it very much is not. It's quantum mechanics, so what's really going on under the hood is wave mechanics of probability functions, where the _wavefront_ is what slows down in a medium. If you could _detect_ an individual photon in one place inside a medium, and then detect the exact same photon in a different place inside that same medium, then yes, it would be shown to have moved at _c._ This makes perfect sense since all materials are still almost entirely vacuum, so on the tiniest quantum scales, all photons are _always_ moving through a vacuum. But you can't measure that. Not even in principle. Not least of all because the photon, as you're thinking about it in _those_ kinds of terms, doesn't exist at all and can't be measured like we're tempted to think in that thought experiment. Instead, you can (and I'm definitely simplifying for concept over full fidelity here) "gather" enough energy to "measure" a photon, but you're "gathering" it from a _wave front_ that is actually moving slower than the speed of light. If you then "gather" another photon from the same wavefront after a short time, you will _genuinely have seen_ that that "source" of photons is moving at less than the speed of light. It's a very tricky, subtle thing, as much of quantum mechanics tends to be, but it _is_ something you can wrap your head around with the right communication techniques and the right foundations of understanding... unlike most physics professors who I think mostly just like to giggle at the confused looks on their students' faces as they explain things the same horribly confusing way _they_ were taught, to propagate the confusion out of little more than tradition.
@@barefootalien great explanation! I can’t say I fully understand, but from what I know of quantum mechanics, that’s kind of par for the course. I’ll just say neither explanation is exactly true, the reality is quantum fuckery.
@@gabor6259 Yeah! I was trying to remember where a good video for that idea was. Hah, never would've guessed 3Blue1Brown. I was trying to think of whether it was Fermilab or the like, but it makes sense with how good he is at illustrating concepts. Thanks for the reminder!
There's another thing about backward time travel: If you travel forward in time (faster than in other reference frames), you don't up end meeting an older version of yourself; as in, the amount of matter or information does not change, you yourself just get there faster from your perspective. Thus applying the same rules, backward time travel should behave the same. You would not change anything, just getting younger and "forgetting" things, not meeting a younger version of yourself. This also neatly solves the grandfather paradox, as it couldn't occur that way.
I semi-recently watched a video where they had a double double slit experiment. I will probably mess the description up but it was something like the activation of the sensors on the last slits were dependant on if what it received was caused as a result of an interference pattern or not. Like I said this is probably a wrong description but the bottom line was that the 2nd measurement was interfering with the earlier measurement. So in that setup causality can work backwards through time.
You are probably talking about delayed quantum eraser. Sabine Hossenfelder explained why it is not a retro causality backwards through time, it is just a wrong interpretation. If we exclude some data post factum we can create an interference pattern based on the results from a second detector and that is it, there is no information travelling backward in time.
Luminal and liminal are different things. Luminal relates to light (lumen) where liminal means to be at the perimeter of an object (example a subliminal message is one that is on the boundary of awareness). As far as I know anyway.
There are two massive problems with time travel that these videos just ignore: conservation of mass, and galactic motion. Virtually everything has mass. If you send a mass back in time, are we adding mass to the universe? Or do the atoms and molecules that make up that mass need to be “re-organized” in the destination timeline to recreate the mass being sent back in time? In the former case it would then seem you could add infinite mass to the Universe, and in the latter could cause a paradox if I travelled within my lifetime (as the matter from me-now would largely come from me-then, killing myself in the past and creating a paradox). And even if we ignored that problem, if I travelling back in time starting from my home considering how fast our planet (and solar system, and galaxy) are moving through the universe, moving _only_ in time would result in being stuck in deep space. Being in the past you’d be _chasing_ the Earth to catch up - so even if you time travelled in some sort of spaceship it could take a long time to actually get to earth to do anything useful.
If you had FTL to travel back in time, im sure getting back to Earth would be a non issue just travel at 99.99999% C until the distance to Earth is short enough from your perspective. Also on the conversation of mass, because these objects would have imaginary mass when sent back surely that evens things out? Not fully sure tho
@@idris4587 - I agree with your first point, except now you need to time travel with a spaceship. That perhaps is not out of the question if you have the technology to get within a nano-percentage of C, but it isn’t how most people tend to conceptualize time travel. Point being, achieving a high enough speed to travel backwards in time likely isn’t sufficient in and of itself, and it may not even be the most difficult problem with time travel. Still, I’ve thought for a while that a sci-fi story about time travel where any matter that travels back in time with you disappears from your destination timeline when you get there - wrecking some havoc in early trips, and requiring a historical analysis of all materials used to travel to ensure you’re not impacting the timeline.
@YaztromoX Yeah for sure most versions of time travel definitely have this problem. The only other verison I could think of would be reverse entropy time travel like in primer and tenet
You should do a video on the radium girls it's quite a horrific video I don't know if you've ever seen it but it's about women that painted watch faces using radium base paint so that way people in the military could see their watches at night because when radio is exposed to light it will absorb the lights that way when it's dark and they can see their watches. And they were taught to do the lick and dip technique which even though we know that radio is just calcium's evil cousin. Because they were told radium is absolutely safe the women began painting their nails their teeth and some documentaries and article say that when they would leave work at night or go out to a bar or the ball that they would have a light glow to them and they're clothes sometimes. And because radio is so close to the makeup of calcium that it absorbs right into the bones and because they were taught to do the lick and dip technique their jaws would be the first thing to go they would normally break they lose teeth and sometimes in some cases they would swell up so badthat it would just create a huge abscess the size of a softball if not bigger and some women would lose their bottom jaw completely. And if they survived all that then they would become so weak that they couldn't even get up and it's a few women that were able to get up their bones would break just under the weight of their own body.
i had a problem with the video and its mainly the notion of curvature at 1:04 the video in question refers to the Universe as 4D (X,Y,Z,W) and most physic papers and vis math will use the W axis as the fourth vector and not time. I view spacetime as one of those subjective arguments. If the Universe is 4D then its a 3D hypersurface curving into the 4th vector as theres no real difference of a 4D cube with or without time you aren't really changing anything and 9/10 unless its some weird thought experiment time is not considered a vector time is change. if the Universe is 3D we know there is 2D+1D spacetime a 2D plane curving into the 3D and this boils down to a weird situation
It seems people don't really understand what they mean with "going back in time". Going fast through time means you age faster. Going slow means you get to see the world age much faster than you. Going backwards as presented in the video would simply mean that you't get younger while everyone around you would still get older. Either way, this does not mean you'd go into the past. What we call "the past" is the ENVIRONMENT at a certain age, not the observer. If you wanted to visit the past and play with dinosaurs, you would have to make the WORLD go back in time around you, not yourself. So the talk about paradoxes and branching timelines is completely irrelevant. If you could make the world go back in time it would simply be a do-over. If somehow you managed to still move forward, to you it would look like a rewinding video.
While watching this video I got anxienty bc I realise photons are arounds at all the time seemingly "invisible". Traveling from the surface of my Tablet into my eyes, reflecting off my skin into my eyes and everything I see is just because of some particles reflecting into me.😂 😭
You can experience the past if you travel across the universe and look through a powerful telescope at Earth. You'd see the light emitted during the years of the dinosaurs but only when it reached that planet you're on. If you could teleport faster than light than yeah sure, you can turn around and see the light finally catch up
Thanks for educating people about nuclear energy. I want to suggest some videos to watch. 1. "The Soviet Union’s Peaceful Nuclear Explosions" from "Asianometry" channel. It is about Soviet and partly USA peaceful nuclear programs. 2. "Closed nuclear fuel cycle: practically inexhaustible energy is already almost within our reach!" from "Terra Physica" channel. It is about fast sodium reactors and well represents the reasons for the development of fast reactors in general. It also contains interesting information that I haven't seen anywhere else on youtube. 3. "Small Misunderstood Reactors" from "Decouple Media" channel. This is a video about SMR. It lasts 1.5 hours, so it's probably not really your format. But it's very interesting.
It appears there is a misconception regarding the essence of time. Humans have historically utilized comparisons to celestial movements to quantify their daily activities. However, contrary to the assertions presented in this video, the concept of time itself may be merely a fallacy. Time is solely a human construct. Numerous scientific hypotheses analyze the motion of particles, waves, and celestial bodies, attributing constants associated with speed to many of them. Nevertheless, it is imperative to recognize that speed is a measurement of distance relative to time. Given that time is simply a human construct, the argument that its existence can be substantiated by repeatedly stating "Time exists," as children do, is fundamentally flawed. This approach deviates from the principles of the scientific method. [AlphaTwelveThetaTwo]
Another physicist content creator agreed that faster than light travel would travel through negative time. I believe in B-series philosophy of time and generally subscribe to determinism. For me, all of space time exists, and the present is an illusion. There may not be a such thing as the present moment anyway because of how time works. So if something goes back in time, than it can't change the past. Whatever effect it causes on the past much necessarily be part of it's present. There's a popular movie that includes toys as part of it's plot, but you don't know that the effects you see were caused by the future until late in the movie. In my view, free will (in the sense of being independent of physics acting on your brain) doesn't exist.
If we ever find a real tachyon, might I suggest the name “GMO particle”? Basically OMG particle but the OMG part is backwards because for the tachyon, we would be saying “OMG particle” instead.
11:40 that's why they said relative to the universe you could travel far away faster than light, look back, and see yourself before you left you're not actually in the past, but relative to the light spreading throughout the universe you are
1:30 An example of time-reversed-decay? A 0.86-MeV neutrino flies in and hits a neutron in the nucleus of an excited atom of lithium-7. The neutron turns into a proton, and the neutrino turns into the electron occupying the vacancy, thereby creating a ground-state beryllium-7 atom. 11:20 Virtual particle exchange has super-luminous particles. The trajectory is spacelike, and in another frame, one has an antiparticle going in the opposite direction. Two charged particles exchange a photon. The photon is spacelike, and in the CoM frame, the photon takes literally zero time; the emission and absorption points are both at the same time. 13:20 In quantum field theory, a tachyon means that the vacuum is unstable. The closest thing that I am aware of to a tachyon is the Higg's field, which has a tachyonic mass term, but also a phi^4th term to stablize space. 17:00 If Lord Kelvin said that, he must have been unaware of birds.
1:30 I guess it would assimilate material from the environment. 2:40 Odd it's not Pythagoras. 11:50 When do you go backwards sub-luminally? 12:45 I'd tend to think it's the same past, with a different future. 13:00 That, I insist, is less paradoxical than the alternative, though drastically less stable/reliable. 13:30 Not negative? 14:30 Well, preventing your own death is possible in a closed loop (or with forethought). 15:30 Realistically, their expected speed would be... around c if they're cosmic rays, but otherwise a negative "normal" value, or a positive value massively over C.
To be fair: We make a lot of assumptions on things that we assume as true. We assume that causality is a law and that you'd either end up with paradoxes or new time lines. But we really don't know if the Universe even cares about the concept of "time lines" We're just assuming that all states happen and that there are branching time lines. This might be necessary in cases where you're creating a simulation of a universe with a single dimension of time but we really don't know if that actually holds true for the Universe. It's all one huge assumption. As to assuming that some particles might exist and making further assumptions about the Universe without their evidence even being confirmed. I wonder how that search for Dark Matter is going? :D
i think you can argue that because we have yet to witness any time travelers from the future, it simply wont ever be "scienced" into existence. Stephen hawking did an experiment on this by planning a time travel party without telling anyone until after it happened, simplified of course here, and who wouldn't want to meet one of the greatest minds of this era.
It was said most scientists say tachyons don’t exist, but if I remember right there was a time that scientists didn’t like Einstein’s theory of relativity or later on were saying it’s impossible to split an atom. While relatively is generally accepted now, the splitting of the atom was actually physically done. My point being despite what theory might point for or against for tachyons, unless concrete proof is proven against them they could exist. Let’s call their existence contingent for now.
Iv never understood why people keep considering just seeing old light from interstellar distances is suddenly time travel. Yet despite that they seem to get the fact we see old light from other star systems from earth isn’t time travel. Its in a way the equivalent of saying watching a old movie suddenly means you’ve time traveled because it’s old instead of new
On the topic of arrow of time, i'd recommend the YT video "Entropic Time" by A Capella Science, if you haven't seen it before. It's a music video, a parody on Billy Joel, but would also be an entertaining reaction, i think. Incredible concept, lyrics, a capella skill and a mindblowing video.
And this is why you shouldn’t think too much about any FTL drive in sci-fi. Fundamentally all of them break causality. If you add FTL to your setting, you are also adding time travel to it (though depending on the FTL method it could be very limited. Star Trek warp drive allows you to fly to the past, but the FTL radio thing from Avatar only lets you send messages back to when you first built the machine)
12:29 One thing that I never understood is why people still think that once one goes back in time (assuming that's possible, d'uh!), the memories are the same. Plus, where would one "land" in the past? One kids story from "Topolino" (Italian's Mickey Mouse comics) kinda stuck in mind: throughout the years of publication, MM and Goofy teamed up with two scientists in a lab (unknown to everyone else but those four) to be time travelers in several stories; in this lab there's this device that can fit 3-ish people that beams whoever's in it in any era of the past at a specific location, and it beams them back in the present after a fix amount of hours always from the same location; the capsule doesn't go with them, it's stationary at the lab; whoever misses such beaming will be trapped forever in the past. This particular story is, they went back 24 hrs to prevent a disaster from happening (a ceremonial ship launching) as it was allover their newspapers; long story short, MM and Goofy managed to prevent it. Beamed back (front?) in the present, they've exited the capsule and were received by two shocked scientists. MM asked to see the papers and indeed, it has never covered the ceremony as it went fluently, so no news there. The last frame of the story were the two scientists babbling between them about time paradoxes and a confused Goofy asking MM if they actually have ever gone back in time: I found that question silly as of course they have had, but thinking about it kinda makes sense as it depends on which reference. And this quite ties to the idea of keeping the memory thru time traveling: all four at first knew what happened, but only two at the end of the mission kept such memory/knowledge. So could it be that time traveling is actually possible (BIG d'uh, but who knows?) as memory will be altered all the... time?
Couldn't you find at what speed time is slower to find a "0 velocity" by measuring various speeds and comparing them? Also, if you travelled back in time, wouldn't you collide with the yourself of the past?
I tried to explain the details in a clear way, but essential time travel is just time travel by convention of description, so it has tk be defined as a macroscopic category of content more or less, or its just an arrow added on with no real function what so ever.
The *big* simplification they're making to simplify the math is that they're leaving out a minus sign. They're describing and illustrating the concept of moving slower through time as you move faster through space, with a spherical relationship that allows for ordinary vector addition (which is very easy to show graphically). The reality is that it's a _hyperbolic_ relationship, which means normal vector addition and its simple illustrative properties don't apply at all, and you need hyperbolic Lorentz Transformations instead. It doesn't really add much to the intuition at a novice level, though, so it's a common science communication trope to go spherical with it. Even Dr. Lincoln at Fermilab did that, using a car in his simplified mind-experiment. Kurzgesagt simplifies even further by not even _admitting_ this part of their simplification, but... I think it's fairly okay. Though I do wish they'd done a little throat-clearing grumpy aside riiiiight around 7:38 in your video.
Ultimately these distinctions about time travel are about physical content, deriving them from physical law a priori is pseudo-science, because physical law is just a convenient way to characterised correlations lf physical content.
who is to say we can only go one direction? Maybe we can go back, just all memory of the future is erased of course, as that hasn't happened yet and as we go back in time, everything rewinds.
I hate the idea constantly proposed that traveling faster than light lets you move backward in time. According to this theory, you would time travel by exceeding the speed of light, then traveling exactly the speed of light (or a marginal fraction off of it) back to your point of origin to enjoy that time travel because you would not change your timeframe. In reality, to me at least, it seems like it would be more like you see light which had been cast off from Earth from those years ago. You aren't actually traveling backward in time, just seeing it. Then traveling back to Earth, you'd get a light speed fast forward to "now". People have brought up the atomic clock factor, how this time travel via speed/gravity has been proven in orbit, etc. There are still too many variables to account for that inaccuracy. Energy is added to the clock's mechanism during launch and orbit which can account for a time difference. Vibrations can ruin calibration. Etc. You could only convince me if two clocks were calibrated in space, then sent in different directions; one probe sent out to the outer edges of our solar system off of our planetary plane, the other sent to orbit our sun in a long and lazy orbit where it gets to experience gravitational hijinx over several years/decades. Only when the probes start reporting time differentials that aren't accounted for by red shift/blue shift would I agree. Otherwise, we're talking theory, and I believe the theory is wrong.
I recently watched terminator zero the animated series there apporach to time travel was intriguing. Its explained that everytime someone goes back in time they create another universe as their presence in the past changes the timeline. However what they do in the last does not change the future they are from as they are now in a separate universe. Since its the terminator films the plot being Skynet killing John to save itself even if it succeeded in killing him it would only effect the other universe so skynet would still die in its universe so no real point in going back as it wont actually change your reality. Not a physicist or engineer i just thought it was a cool idea for the show
Light is an electromagnetic oscillation. How can you have an oscillation without time? Oscillation is by definition change, change only happens overtime.
tachyons i found to be a interesting theory and especially when it comes to energy given infinite energy and imaginary mass i find to be a cool topic even if its like you know not entirely been proven and that we wouldn't be able to perceive them
could you do a reaction to the video "Breaking Physics Using Math" by MAKiT. its similar to this one, but explores more concepts and breaking them using math. also prevent yourself from dying implies, you have already died... but if were talking time travel what else is possible in that universe
At light-speed, not only would nothing be visible (light cannot move relative to you), but you would also 'immediately' crash into a wall. You are traveling at a finite speed over zero time, you cannot slow down without external help. If you were to travel faster than light somehow, you would crash into the wall before you started moving. We fix the weirdness of this by moving the future self into the past, your endpoint becomes the present when you start moving, clamping velocity to lightspeed through negative time.
Doesn't special relativity mean that c is constant, whether you are stationary or moving at c? Even if you were at c and you measured the time it took light to travel, you would still measure it at 300,000km/s. That's my interpretation of it, though practically it makes no sense but I am not a physicist.
2 месяца назад
What you think when I say "time travel" isn't possible. We can make it look kind of possible with numbers and letters because we have a limited understanding of the universe and physics.
People put WAAAAAY too much emphasis on Einstein's special relativity, wherein the "special" part is that is isn't based in reality. Yet almost no one consistently puts emphasis on his ACTUAL theory of relativity, which is an expression of observable reality. Since we live in reality, SPECIAL relativity is just science fiction, and it always was. Einstein himself was the first to acknowledge this objective fact.
And yet we kinda live in the past all the time, since everything we see, well light takes a bit of time to hit our eyes, and then the signals to move around the body. So we never see things as they are right here and now in this very moment, always a bit in the past
4:05 you should clarify that the photons arent actually slowed down. the medium creates waves but phase shifted these ínterfere with the light making it apparently slower but not actually.
To travel backwards, you need to go faster than light, which somehow is impossible. The universe will stretch space, co tract time, all just so that you're not faster than light from any perspective
@@borttorbbq2556 the universe expands faster than light or rather two points given they're far away enough that light doesn't reach to travel from one to another before the distance increases is a concept I don't understand, but it does make sense to have an observer Al universe, since we can only see stuff light is fast enough to travel from and reach us
The inaccuracies in these videos are astounding. At 3:50, the video shows a photon moving in a flat plane across the space axis (because it's moving at C). That is wholly incorrect. All paths of light in a space/time graph move at 45° angles as that is the only way to equate different inertial reference frames to eachother. "Time" is at a stop for photons because of that 45° angle. It's distance traveled along the space axis is exactly equal to its progression up the time axis. Also, the second law of thermodynamics is so poorly understood by most. It clearly references entropy in a CLOSED system which rarely exists in our universe. Those laws were created through thought experiments to describe outcomes within the parameters outlined. The other law that gets severely misunderstood is the first law, conservation of energy. It was created with very minimal understanding at the time. It only takes in to account the energy that was know of at the time, with no accounting for vacuum energy and quantum fluctuations. There needs to be a concerted event to rewrite these laws to incorporate evolving knowledge instead of pushing these "laws" as hard limits.
You're right if we were talking about a spacetime diagram (which is 2d, space and time dimension), but what they are showing is something strange 3d. I have no idea what they are trying to do here...
Also incorrect the second law of thermodynamics is not talking about a closed system it's talking about an isolated system. A closed system is different from a isolated system, although a lot of people will get it mixed up or just use the terms interchangeably
@ariantes221 in terms of "space and time", 2d is sufficient to quantify the result since the "space" axis incorporates the 3 dimensions of space and the diagram doesn't change regardless of which direction in space the reference frame takes i.e. going up or left or forward or down etc through space won't change the outcome. This same diagram CAN be drawn 3 dimensionally and should actually always be thought of in that sense.
(I think just about all of this is HIGHLY speculative and SC-FI at best) but let’s remember powered flight was science fiction only 124 years ago, traveling to space or the moon the same. Take a cell phone back 200 years that’s well within 2-4 generations with good genetics, and you are a sorcerer or a witch. Which is why physics and the cosmos is so infatuating. I believe will will learn and see stuff at some point that would be to our modern life equal to magic.
3:30 Changing time dimension speed is completely wrong in this context, your velocity away from other spacetime events delays observation of photons coming from the events but speeds up any photons come of from events in front of your geodesic
And yeah, a causal principle is just a way to state the physical content that is independent of representation with regard to what would be real in a world like that proposed by the principle, like any other physical content. Its useful but not objectively true in the same way a fact is, like whether a measurment comes out a certain way, which is independent of representation. A causal structure that by construction picks out a frame for simultaneity is perfectly fine and doesn't conflict witb special relativity at all, and could serve as the definition of what goes forward or backwards conceptually, as an organising piece of contents physically, and our conversations that are important for word only could map naturally onto thst structure in a way that allows no macroscopic time travel, only time travel by convention. Its something like everu degruof freedom having a physical feature that gets bigger with time for example, like the counting of a digital clock or the aging of a person, bssed of physics content alone, then there is an objective fact about time traveluwitb respect to such macroscopic concepts of change, time travel cant be a consequence of something fundamental like trajectory, it would have to be something like ending up with a loop where some stuff changes lile age along tje entire loop, and then its only time travel relationally, fundamentally there are no such coherent concepts, just conventions of description. If you want something approximately like an objective answer to whether time is traversable then its only coherent with respect to such relations, and every oart of a physical theory appart from coordinates or representation must be relationally defined for that to make much sense, only the macroscopic relational concept of time evolution is meaningful like i said a million times in different ways already because i fear i have not made myself quite clear. You are totally right to think about the principle of causality, but that is a relational concept really which needs a mechanism that is more or less macroscopic through and through to avoid the pitfalls of convention beyond tirvial representation. Basically for the concept of time evolution to be something more than a parameterisation of some mathematical functions it must be just macroscopic in a sense, it has to je a pattern without any fundamental description, which means that mathematics strictly speaking cannot account for causation and time evolution in a faithful way. This is somewhat hard to force you to buy into, but its also simple, its still just a pattern, but within it, forward and backwards is just defined by the pattern, tje pattern is defined by itself, and there is no fundamental entities other than the whole, even witj infinite densifuof detail, it is not possible to write down the mathematical forms for this exactly, and it doesn't solve the problem by not needed to be labled with coordinates and given representation, rather it is obvious that any physical content what so ever is encoded in itself we no longer have ti think about what it means fir a function to be a physical law, or a time parameter to be physicsal, time is simply just a pattern of relations that unforlds in the pattern its a tranformer of itself for space and time, just an answer to what exists, plain and simple, independent of space and time any part of it is related in a way where you could do something like analytic continuation from one part, no matter how small a subset to the whole, the only problem is that the mathematics doesn't exist and cannot exist to describe it at uts own level of detail, only abstract properties can be described not the object itself. And the relevance might be confusing to you, it doesn't seem to solve these issues, but the kicker is that any physical theory has these properties as well, its just not enshrined in our representations because treat content differently from law, when that is just a fallacy concocted by the human brain, fir no reason traceable by man other tha mistsken desires for our project to be more coherent than it is, mostly because of a misconception about method, it just because it feels right ti say that theory is predictive only if if doesn't get defined by what happens, like an account of how your day went rather than laws of how a nuclear engineer eats dinner. The reason is that we think its related to how predictive a theory is, but this is wrong, a theory by decree of physical content is more predictive than a physical law that describes the form of correlations within it, this is obvious whennwe out it like that, a physical law is just a way to group many theories by decree by the form of correlation in its content, if the law as defined by tje content in a tjeory like i described then the choices become one, and any such theory is completely unique in content and law, andnthe world could only given its state converge on a unique theory like that as long as we don't run into imperical limits, therefore by virtue of uniqueness of existence as a property, if sucj a theory is true, it is unquiqe innits existence as well, whether we can know what it is or not. Anyway this one was a bit crazier, but still true, and statements such as time is running this way or that by convention in sucj a theory, is a obviously meaningless statement outside just relations in the pattern as a whole, whether time travel exists is simply a question of features existing or not. Things like the grandfather paradox also just a feature of content, if its real, then if you kill your own grandpa it cannot lead bsck to your death stopling your actions, but maybe in a different dimension of time evolution that looks identical to you, that emerges as a copy of part of the pattern inside itself evolving after than point in a different direction even if it looked identical, again this entire thing could be described as only forward time evolution with no fundamental travel. As you said, in a different branch. But at the end of the day just correlated physical content.
wait but if everything is moving through time at the same speed it means that if you went back in time then there would be nothing right ? everything is in the present
Observable time, relative time and Liminal time. Observable time is what we see passing. Relative time is Observable Time from another perspective in space. Liminal Time is the difference between Observable and Relative Time measured.
I do not believe in anything stating that you can go backward in time. There is literally nothing to go back to. The past doesn't exist once time passes. It is gone. Time goes in one singular direction. anything else is nonsense.
actually the speed of light isn t reduce it is defracted making it take alonger joury and its is still in that longer journey gpoing at the speed of light. So its only relatively slower than light. No light is both wave an [article modern physucs has relized this it rue for all objects particles and waves are basiclly defiing diffrent aspects of the same object.
Keep in mind: there is no way to transition from superluminal to subluminal speed, just like there is no way to transition from subluminal to superluminal, so normal matter cannot be sent back in time. Similarly, if tachyons exist, they are detected before they are emitted; if you emit one and it is detected in the past, then it was already detected, and you have not actually altered the past. If a tachyon was never detected, then the one you emit will not have been detected. We have never detected a tachyon, so we know for certain that no message will ever be successfully be sent back in time to 2024, and there will be no paradoxes (yet). This does not necessarily preclude sending information back in time, if tachyons can exist; however, if they do exist, they likely do not interact with particles whose mass does not have an imaginary component. They likely would be created in tachyon-antitachyon pairs with conjugate mass, and only interact with other tachyons or by annihilating with antitachyons.
It goes like this: you go so fast you trip, you are not running anymore, what is the opposite of running? Backwards! So now you are moving backwards in time, the inverse of moving forward, and now you can just go to the past! IS LITERALLY THAT EASY! I DON'T KNOW WHAT ALL THE PHYSICIST ARE COMPLAINING ABOUT!!!
If you say light moves through water at about 2/3c, does that mean nothing can ever go faster through water than 2/3c? Maybe you can go faster than 2/3c through water if you deliver energy from beyond the water to this moving object.
you can go faster than the literal speed at which photons move through some sort of medium like water, the blue radiation picture he showed when he mentioned that is an actual example of this happening. the Speed of Light, c (2.999...*10^8 m/s), is a universal constant, and can never change. Nor can something move faster than c. calling it the speed of light is just a name, it's the speed at which any massless particle moves at.
Would be possible to gain the energy just not within our universe. But that would take heaps of knowledge and for people to figure that out we would be a different evolved species by then probs lol
you would have to restore the state the universe was in... to do that you would have to bring every single atom, every single electron and quantum particle into the state it was in at the time you want to travel to... of course you would need more energy than the universe contains... you just can't move anything without using energy... I mean.... if you want to move all the energy in the universe... where would the energy to move it come from?... bottom line... I would disagree...
@katchou1337 it's a higher demotion problem that we don't understand yet. The answer could be in where gravity works if that's a higher dimension problem. We're not the centre of the universe why would we be the centre of reality? Lol. We've been wrong about alot of things in science and may even be less of the energy of our universe to do it. But you wouldn't need to replace the universe just need it intact still. If you only think within our universe it can be very limiting. There's a new theory of how our universe began like a universe colidding with another and forming the matter we know now
Short story shorter, the moral of the story is, we tesch special relativity in a dumb way, as a result even physics get this stuff completely wrong when discussing FTL travel, coordinates and representation os irrelevant to ordering in time only local causal ordering, what precedes what causally defines ordering in time and therefore time travel is only dedined by a reversal in the local causal ordering that cannlead to loops special relativity or general relativity neither bars such things or predicts it, to any degree stronger than Newtonian mechanic does, read the long comment, but essentially if you want to have it you have to without exception out it into the local dynamically defined causal ordering by hand, and claims to the contrary, are claims that coordinates have physical meaning or that choice of representation have physical meaning and thats simply a misconception about physics. Prominent professors make this mistake because they are quite frankly a bit weak mathematically and doesn't get the point of relational physics, where the dynamical relationships that are independent of coordinates define everything that is real in the physics. This is the original motivation for special and general relativity and they get it wrong, Einstein was also a bit wrong about it, but thats another matter, he was considering a theory of dynamical relations where nothing moves faster than light anyway and so, from that perspective the errors related to abuse of coordinates and time travel just dont come up, because the causal structure that defines the local ordering is the fastest thkng around, that means the local ordering cannot be messed uo by hand by abusing coordinate transformations such that you put it in by hand thinking that its the theory that is doing it for you, while you are just innocently doing positive velocities faster than light in different references frames, but its nonsense, they out it in by hand. Incan do that in newton look, the trajectory of a ball in Newtonian spacetime is a circle that loops back on itself in the time dimensions, i just derives time travel as a consequence of absolute soace and time, well, no i didnt, what i did do is draw a circle in a diagram and point to it, the people who think time travel is a consequence of special relativity and faster than light motion are doing the exact same thing, only doing a bunch of coordinate transformations while doing it, basically drawing a circle on a canvas while deforming it, thats still just putting it in by hand, and the people who think otherwise should go study harder maybe, because they are making trivial errors.
I know you Know this, but as you said, so far they haven't, they already made a huge mistake of saying sum instead of the sum of squares under a square root but okey. Straight out of the gate they said something completely wrong. And i wont even attempt to comment further on this video, because why would i, its just going to be wrong in all sorts of ways, i'm usually in that headspace about professors getting special relativity wrong as well, because they do, and the way it is taught is also mostly wrong, they teach one type representation of the underlying physics in special relativity, as if its a unique theory, when its not, Einstein made the same mistake to be fair, its not like this is new to the literature or anything like that, it was mostly worled it before Einstein was even writing the first special relativity paper, and then he made somw bad choices lets say, but the theory he produced is the simplest to use representation of the physics, but the convention like i told you before on a veratasium video, that he used, is arbitrary and leads to a mistaken view of what the theory says if you thinknthe postulate about the one way speed of light is physical and not a matter if representation. But thats okey, the resulting theory can be used for calculation without error so its not a problem to work with it, but it is like thinking long division is why division works or that long division is a oart of how division is defined, which is just plain nonsense.
Oh, I'm a computer engineer and I was just offered a job with the military working nuclear. Do you think I should consider it or should I just not respond?
welp they did say you'd be angry
And Tyler even tried to break down the door to protest too in that clip :D
But he’s not a physicist. He’s a nuclear engineer.
@@nathanpfirman625can one be a nuclear engineer without being a physicist?🤔
@@aidarosullivan5269 In the USSR I think you could :3
@@aidarosullivan5269 Jokes aside. As someone that knows next to nothing about being a nuclear engineer. I assume you realistically don't actually need to understand the atomic physics behind what you do, just the properties of physics at play. A civil engineer doesn't need to necessarily know the atomic properties of water to design a bridge that will be in water, just be able to understand a datasheet with the physics related properties that will impact a bridge. Things like, it will corrode metal at whatever rate if not painted and hoe much pressure it will inflict at whatever depth and whatever speed, and then be able to do the math.
So, being a physicist would help to actually understand the deeper physics at play, but is it required? Maybe legally to work in a nuclear power plant? But like, actually required? I can't say I know :D
Remember space travelers, if you go back in time don't sleep with your mom.
But you can sleep with this guys mom.
Great Scott! That's heavy!!
I kinda feel that the words "if you go back in time" are superfluous.
But I don't I won't exist! it's a cannon event.
Marty McFly reference
"You could theorize the existence of a ten thousand dimensional object"
I see you've spoken to a String Theorist before
Haha
"The blue glowy thing" I just applied to tour a reactor and really hope I get to see some Cherenkov radiation.
Thanks for the upload!!
843 days of space journeys of a man allowed him to age slower than us in orbit by 0.022 ms
Yet this guy wants to question if the same thing is true around a blackhole.. we literally have to adjust the clocks on GPS satellites do to the speed they move at. We don't need to observe it at a blackhole as well. He isnt questioning gravity and we have no idea what causes it other than mass when everything else has a particle or wave.
@@KeanueAnakoni-Aukai Im pretty sure he meant engineering wise if its possible to travel all that way and back
@@KeanueAnakoni-Aukaidunning Krueger effect spotted! How about you go learn physics from something that isn’t RUclips videos
Can we go back in time? Let's break the laws of physics to break the laws of physics.
Sounds fun. I'm in.
Me too
Time travel is possible but really challenging
That's exactly what a sad and angry engineer would say...
you can technically get into the past relatively to a given object if you could somehow leave its time cone, but you can't interact with it, only observe its past version from the distance
and key word: relatively, because our planet is inhabited by the dinosaurs for an observer that's 70m light years away or it's not even present for someone on the other side of the universe, so you could say they're several billion years in the past relatively to our planet and vice versa
light cones are defined by the speed of light, if you could observe something outside of your light cone then that'd mean that light is somehow moving faster than c, which isn't possible
So if the light emanating from earth is an ever expanding sphere in space. (moving at light speed of course) Then in order to see into the past (and/or interact with it) you would have to ascend into the 4th dimension and become what we would consider an omnipotent being. Which, from my very surface level 2 minute read of the light cone wiki, would be the only way to actually leave the light cone right?
@@ShrimpInACoffin either that or find a way to create wormholes
Just moving away from any given object faster than light will make it appear to go back in time because you're outside of its present light cone
But if you approach the earth at FTL speeds, the time will seem to run faster on it, so in reality you can't get to earth's past when travelling faster than light, you can only observe it
Even then if you plug something like 2c speed into time dilation formula, weird things will happen because you'll move in complex time
16:55 ... A little correction regarding heavier than air flight. Within a YEAR of Lord Kelvin's infamous quote - so 1896 - Sir Lawrence Hargraves took flight from Stanwell Park Beach - just a few kilometres from me in southern Sydney, Australia - suspended from one of his boxkite designs. Wright Brothers was POWERED flight ... which is, admittedly, slightly more impressive than hanging from and oversized kite, but Australia doesn't have much historical scientific "clout". The kinda cool thing is that to this day, Hargraves' discovery is honoured by hundreds of hang-gliders and paragliders, etc. taking flight each day (coditions permitting) from the hill above the beach.
Entropy isn't chaos, entropy can be used to get a more orderly pile.
like enough order to create the proper conditions required to sustain life?
was just watching interstellar and your comment made me think about the scene when they were deciding between edmund's and mann's planet to land on and they discussed how the black hole didnt allow enough events to happen which means a lower chance of the planet being habitable.
@@julius7949yes, entropy can decrease in a system as long as that system is not isolated.
Meaning you can have negative entropy as long as entropy increases elsewhere.
I have the same problem with tachyons as I do hawking radiation. The math checks out for both, but there has been zero experimental evidence for either one.
You never know though. So many things in physics have been "discovered" on paper first.
@@Shoomer1988 I agree, black holes are the same way. But we now have direct observations of black holes confirming their existence. Just because something exists on paper doesn't mean it exists in reality. Observations are needed.
Light isn’t slower in water, it simply can’t take the direct route through it
I like your line of thought! It isn't _quite_ true, though.
The reality is more complicated than either of those simplified concepts. The idea that light is slower in media other than vacuum because it bounces around and takes indirect paths is pretty neatly countered by the fact that transparent materials exist. If that was the reason, then those bounces would be in random directions. Everything would do full random scattering, like paper, and we'd have no windows or mirrors. Depending on how you interpret the concept, no color, either. Clearly we have mirrors and windows _and_ color, so something else is going on. 🤔
And yet, nor does "a photon" actually "slow down" in a medium with a high refractive index. You'll never see that happen, can never measure it to be the case, no matter how much technology you get access too, because it isn't actually happening at all. But... underlying that is the fairly mind-blowing fact that "a photon" isn't _really_ a valid concept in and of itself. At least, not if you think of it as "an object", which it very much is not.
It's quantum mechanics, so what's really going on under the hood is wave mechanics of probability functions, where the _wavefront_ is what slows down in a medium. If you could _detect_ an individual photon in one place inside a medium, and then detect the exact same photon in a different place inside that same medium, then yes, it would be shown to have moved at _c._ This makes perfect sense since all materials are still almost entirely vacuum, so on the tiniest quantum scales, all photons are _always_ moving through a vacuum. But you can't measure that. Not even in principle. Not least of all because the photon, as you're thinking about it in _those_ kinds of terms, doesn't exist at all and can't be measured like we're tempted to think in that thought experiment.
Instead, you can (and I'm definitely simplifying for concept over full fidelity here) "gather" enough energy to "measure" a photon, but you're "gathering" it from a _wave front_ that is actually moving slower than the speed of light. If you then "gather" another photon from the same wavefront after a short time, you will _genuinely have seen_ that that "source" of photons is moving at less than the speed of light.
It's a very tricky, subtle thing, as much of quantum mechanics tends to be, but it _is_ something you can wrap your head around with the right communication techniques and the right foundations of understanding... unlike most physics professors who I think mostly just like to giggle at the confused looks on their students' faces as they explain things the same horribly confusing way _they_ were taught, to propagate the confusion out of little more than tradition.
@@barefootalien great explanation! I can’t say I fully understand, but from what I know of quantum mechanics, that’s kind of par for the course. I’ll just say neither explanation is exactly true, the reality is quantum fuckery.
@@barefootalien 3blue1brown said that a material kicks back the phase of a photon. Do you like that explanation?
@@barefootalien I thought they just averaged the same direction. Interesting.
@@gabor6259 Yeah! I was trying to remember where a good video for that idea was. Hah, never would've guessed 3Blue1Brown. I was trying to think of whether it was Fermilab or the like, but it makes sense with how good he is at illustrating concepts.
Thanks for the reminder!
I like the retrocausality explanation for the 2 slit experiment - which is tiny time travel
Retrocausality in the delayed choice quantum eraser is a nonsense misconception lol
There's another thing about backward time travel: If you travel forward in time (faster than in other reference frames), you don't up end meeting an older version of yourself; as in, the amount of matter or information does not change, you yourself just get there faster from your perspective.
Thus applying the same rules, backward time travel should behave the same. You would not change anything, just getting younger and "forgetting" things, not meeting a younger version of yourself. This also neatly solves the grandfather paradox, as it couldn't occur that way.
I semi-recently watched a video where they had a double double slit experiment. I will probably mess the description up but it was something like the activation of the sensors on the last slits were dependant on if what it received was caused as a result of an interference pattern or not. Like I said this is probably a wrong description but the bottom line was that the 2nd measurement was interfering with the earlier measurement. So in that setup causality can work backwards through time.
You are probably talking about delayed quantum eraser. Sabine Hossenfelder explained why it is not a retro causality backwards through time, it is just a wrong interpretation. If we exclude some data post factum we can create an interference pattern based on the results from a second detector and that is it, there is no information travelling backward in time.
Can we see more videos like this, I thought endorsing getting physicists mad was funny
I am a physicist, and I’m not angry…just insanely curious and confused…it just looks like we’re mad.
It wasn't until the whole liminal space fad that I heard liminal be used in context other than super liminal.
Luminal and liminal are different things. Luminal relates to light (lumen) where liminal means to be at the perimeter of an object (example a subliminal message is one that is on the boundary of awareness). As far as I know anyway.
@@HardwareHarry There was a reply here. I don't know where it went.
There are two massive problems with time travel that these videos just ignore: conservation of mass, and galactic motion.
Virtually everything has mass. If you send a mass back in time, are we adding mass to the universe? Or do the atoms and molecules that make up that mass need to be “re-organized” in the destination timeline to recreate the mass being sent back in time? In the former case it would then seem you could add infinite mass to the Universe, and in the latter could cause a paradox if I travelled within my lifetime (as the matter from me-now would largely come from me-then, killing myself in the past and creating a paradox).
And even if we ignored that problem, if I travelling back in time starting from my home considering how fast our planet (and solar system, and galaxy) are moving through the universe, moving _only_ in time would result in being stuck in deep space. Being in the past you’d be _chasing_ the Earth to catch up - so even if you time travelled in some sort of spaceship it could take a long time to actually get to earth to do anything useful.
If you had FTL to travel back in time, im sure getting back to Earth would be a non issue just travel at 99.99999% C until the distance to Earth is short enough from your perspective.
Also on the conversation of mass, because these objects would have imaginary mass when sent back surely that evens things out? Not fully sure tho
@@idris4587 - I agree with your first point, except now you need to time travel with a spaceship. That perhaps is not out of the question if you have the technology to get within a nano-percentage of C, but it isn’t how most people tend to conceptualize time travel. Point being, achieving a high enough speed to travel backwards in time likely isn’t sufficient in and of itself, and it may not even be the most difficult problem with time travel.
Still, I’ve thought for a while that a sci-fi story about time travel where any matter that travels back in time with you disappears from your destination timeline when you get there - wrecking some havoc in early trips, and requiring a historical analysis of all materials used to travel to ensure you’re not impacting the timeline.
@YaztromoX Yeah for sure most versions of time travel definitely have this problem.
The only other verison I could think of would be reverse entropy time travel like in primer and tenet
To be fair, if you time travel by breaking the light barrier, the hard part is not going too far.
You should do a video on the radium girls it's quite a horrific video I don't know if you've ever seen it but it's about women that painted watch faces using radium base paint so that way people in the military could see their watches at night because when radio is exposed to light it will absorb the lights that way when it's dark and they can see their watches. And they were taught to do the lick and dip technique which even though we know that radio is just calcium's evil cousin. Because they were told radium is absolutely safe the women began painting their nails their teeth and some documentaries and article say that when they would leave work at night or go out to a bar or the ball that they would have a light glow to them and they're clothes sometimes. And because radio is so close to the makeup of calcium that it absorbs right into the bones and because they were taught to do the lick and dip technique their jaws would be the first thing to go they would normally break they lose teeth and sometimes in some cases they would swell up so badthat it would just create a huge abscess the size of a softball if not bigger and some women would lose their bottom jaw completely. And if they survived all that then they would become so weak that they couldn't even get up and it's a few women that were able to get up their bones would break just under the weight of their own body.
i had a problem with the video and its mainly the notion of curvature at 1:04 the video in question refers to the Universe as 4D (X,Y,Z,W) and most physic papers and vis math will use the W axis as the fourth vector and not time. I view spacetime as one of those subjective arguments. If the Universe is 4D then its a 3D hypersurface curving into the 4th vector as theres no real difference of a 4D cube with or without time you aren't really changing anything and 9/10 unless its some weird thought experiment time is not considered a vector time is change. if the Universe is 3D we know there is 2D+1D spacetime a 2D plane curving into the 3D and this boils down to a weird situation
It seems people don't really understand what they mean with "going back in time". Going fast through time means you age faster. Going slow means you get to see the world age much faster than you. Going backwards as presented in the video would simply mean that you't get younger while everyone around you would still get older. Either way, this does not mean you'd go into the past. What we call "the past" is the ENVIRONMENT at a certain age, not the observer. If you wanted to visit the past and play with dinosaurs, you would have to make the WORLD go back in time around you, not yourself. So the talk about paradoxes and branching timelines is completely irrelevant. If you could make the world go back in time it would simply be a do-over. If somehow you managed to still move forward, to you it would look like a rewinding video.
Also, bananas provide scale.
While watching this video I got anxienty bc I realise photons are arounds at all the time seemingly "invisible". Traveling from the surface of my Tablet into my eyes, reflecting off my skin into my eyes and everything I see is just because of some particles reflecting into me.😂 😭
Dr. Nick Herbert has a great book called “Faster Than Light superluminal loopholes in physics.” It’s a pretty fun book if you ever come across it.
As an engineer, you are correct. Time travel would be very useful for solving problems 😂
You can experience the past if you travel across the universe and look through a powerful telescope at Earth. You'd see the light emitted during the years of the dinosaurs but only when it reached that planet you're on. If you could teleport faster than light than yeah sure, you can turn around and see the light finally catch up
Gravity waves are an information wavefront
Please ask penrose to contact me
Lol 😂
@@sylvann7501 im serious, i solved his puzzle
🤦
Thanks for educating people about nuclear energy. I want to suggest some videos to watch.
1. "The Soviet Union’s Peaceful Nuclear Explosions" from "Asianometry" channel.
It is about Soviet and partly USA peaceful nuclear programs.
2. "Closed nuclear fuel cycle: practically inexhaustible energy is already almost within our reach!" from "Terra Physica" channel.
It is about fast sodium reactors and well represents the reasons for the development of fast reactors in general. It also contains interesting information that I haven't seen anywhere else on youtube.
3. "Small Misunderstood Reactors" from "Decouple Media" channel. This is a video about SMR. It lasts 1.5 hours, so it's probably not really your format. But it's very interesting.
Because the time is relative to you, wouldn't you get younger if you went in negative time
Another amazing video, thanks a lot
It appears there is a misconception regarding the essence of time. Humans have historically utilized comparisons to celestial movements to quantify their daily activities. However, contrary to the assertions presented in this video, the concept of time itself may be merely a fallacy.
Time is solely a human construct. Numerous scientific hypotheses analyze the motion of particles, waves, and celestial bodies, attributing constants associated with speed to many of them. Nevertheless, it is imperative to recognize that speed is a measurement of distance relative to time. Given that time is simply a human construct, the argument that its existence can be substantiated by repeatedly stating "Time exists," as children do, is fundamentally flawed. This approach deviates from the principles of the scientific method. [AlphaTwelveThetaTwo]
Another physicist content creator agreed that faster than light travel would travel through negative time.
I believe in B-series philosophy of time and generally subscribe to determinism. For me, all of space time exists, and the present is an illusion. There may not be a such thing as the present moment anyway because of how time works.
So if something goes back in time, than it can't change the past. Whatever effect it causes on the past much necessarily be part of it's present. There's a popular movie that includes toys as part of it's plot, but you don't know that the effects you see were caused by the future until late in the movie.
In my view, free will (in the sense of being independent of physics acting on your brain) doesn't exist.
If we ever find a real tachyon, might I suggest the name “GMO particle”? Basically OMG particle but the OMG part is backwards because for the tachyon, we would be saying “OMG particle” instead.
genetically modified organism particle
11:40 that's why they said relative to the universe
you could travel far away faster than light, look back, and see yourself before you left
you're not actually in the past, but relative to the light spreading throughout the universe you are
1:30 An example of time-reversed-decay? A 0.86-MeV neutrino flies in and hits a neutron in the nucleus of an excited atom of lithium-7. The neutron turns into a proton, and the neutrino turns into the electron occupying the vacancy, thereby creating a ground-state beryllium-7 atom.
11:20 Virtual particle exchange has super-luminous particles. The trajectory is spacelike, and in another frame, one has an antiparticle going in the opposite direction. Two charged particles exchange a photon. The photon is spacelike, and in the CoM frame, the photon takes literally zero time; the emission and absorption points are both at the same time.
13:20 In quantum field theory, a tachyon means that the vacuum is unstable. The closest thing that I am aware of to a tachyon is the Higg's field, which has a tachyonic mass term, but also a phi^4th term to stablize space.
17:00 If Lord Kelvin said that, he must have been unaware of birds.
1:30 I guess it would assimilate material from the environment.
2:40 Odd it's not Pythagoras.
11:50 When do you go backwards sub-luminally?
12:45 I'd tend to think it's the same past, with a different future.
13:00 That, I insist, is less paradoxical than the alternative, though drastically less stable/reliable.
13:30 Not negative?
14:30 Well, preventing your own death is possible in a closed loop (or with forethought).
15:30 Realistically, their expected speed would be... around c if they're cosmic rays, but otherwise a negative "normal" value, or a positive value massively over C.
To be fair: We make a lot of assumptions on things that we assume as true. We assume that causality is a law and that you'd either end up with paradoxes or new time lines. But we really don't know if the Universe even cares about the concept of "time lines" We're just assuming that all states happen and that there are branching time lines. This might be necessary in cases where you're creating a simulation of a universe with a single dimension of time but we really don't know if that actually holds true for the Universe.
It's all one huge assumption.
As to assuming that some particles might exist and making further assumptions about the Universe without their evidence even being confirmed. I wonder how that search for Dark Matter is going? :D
i think you can argue that because we have yet to witness any time travelers from the future, it simply wont ever be "scienced" into existence. Stephen hawking did an experiment on this by planning a time travel party without telling anyone until after it happened, simplified of course here, and who wouldn't want to meet one of the greatest minds of this era.
It was said most scientists say tachyons don’t exist, but if I remember right there was a time that scientists didn’t like Einstein’s theory of relativity or later on were saying it’s impossible to split an atom. While relatively is generally accepted now, the splitting of the atom was actually physically done. My point being despite what theory might point for or against for tachyons, unless concrete proof is proven against them they could exist. Let’s call their existence contingent for now.
Iv never understood why people keep considering just seeing old light from interstellar distances is suddenly time travel.
Yet despite that they seem to get the fact we see old light from other star systems from earth isn’t time travel.
Its in a way the equivalent of saying watching a old movie suddenly means you’ve time traveled because it’s old instead of new
On the topic of arrow of time, i'd recommend the YT video "Entropic Time" by A Capella Science, if you haven't seen it before. It's a music video, a parody on Billy Joel, but would also be an entertaining reaction, i think.
Incredible concept, lyrics, a capella skill and a mindblowing video.
And this is why you shouldn’t think too much about any FTL drive in sci-fi. Fundamentally all of them break causality. If you add FTL to your setting, you are also adding time travel to it (though depending on the FTL method it could be very limited. Star Trek warp drive allows you to fly to the past, but the FTL radio thing from Avatar only lets you send messages back to when you first built the machine)
Love your stuff😊
12:29 One thing that I never understood is why people still think that once one goes back in time (assuming that's possible, d'uh!), the memories are the same. Plus, where would one "land" in the past?
One kids story from "Topolino" (Italian's Mickey Mouse comics) kinda stuck in mind: throughout the years of publication, MM and Goofy teamed up with two scientists in a lab (unknown to everyone else but those four) to be time travelers in several stories; in this lab there's this device that can fit 3-ish people that beams whoever's in it in any era of the past at a specific location, and it beams them back in the present after a fix amount of hours always from the same location; the capsule doesn't go with them, it's stationary at the lab; whoever misses such beaming will be trapped forever in the past.
This particular story is, they went back 24 hrs to prevent a disaster from happening (a ceremonial ship launching) as it was allover their newspapers; long story short, MM and Goofy managed to prevent it. Beamed back (front?) in the present, they've exited the capsule and were received by two shocked scientists. MM asked to see the papers and indeed, it has never covered the ceremony as it went fluently, so no news there. The last frame of the story were the two scientists babbling between them about time paradoxes and a confused Goofy asking MM if they actually have ever gone back in time: I found that question silly as of course they have had, but thinking about it kinda makes sense as it depends on which reference.
And this quite ties to the idea of keeping the memory thru time traveling: all four at first knew what happened, but only two at the end of the mission kept such memory/knowledge. So could it be that time traveling is actually possible (BIG d'uh, but who knows?) as memory will be altered all the... time?
The reason the black hole thing hasn't happened yet is because it's not possible right now
From one's perspective, time always flows at the speed of c, the entire "time dilation" looks more like optical effect.
Couldn't you find at what speed time is slower to find a "0 velocity" by measuring various speeds and comparing them?
Also, if you travelled back in time, wouldn't you collide with the yourself of the past?
To travel to the past, you just need to reach 88mph
I tried to explain the details in a clear way, but essential time travel is just time travel by convention of description, so it has tk be defined as a macroscopic category of content more or less, or its just an arrow added on with no real function what so ever.
The *big* simplification they're making to simplify the math is that they're leaving out a minus sign.
They're describing and illustrating the concept of moving slower through time as you move faster through space, with a spherical relationship that allows for ordinary vector addition (which is very easy to show graphically).
The reality is that it's a _hyperbolic_ relationship, which means normal vector addition and its simple illustrative properties don't apply at all, and you need hyperbolic Lorentz Transformations instead.
It doesn't really add much to the intuition at a novice level, though, so it's a common science communication trope to go spherical with it. Even Dr. Lincoln at Fermilab did that, using a car in his simplified mind-experiment.
Kurzgesagt simplifies even further by not even _admitting_ this part of their simplification, but... I think it's fairly okay. Though I do wish they'd done a little throat-clearing grumpy aside riiiiight around 7:38 in your video.
Ultimately these distinctions about time travel are about physical content, deriving them from physical law a priori is pseudo-science, because physical law is just a convenient way to characterised correlations lf physical content.
who is to say we can only go one direction? Maybe we can go back, just all memory of the future is erased of course, as that hasn't happened yet and as we go back in time, everything rewinds.
11:10-Even this way is not timetravel into the past.
This is basically just bringing your past self into the present.
Maybe.
10:12 Finally someone who's contrary to the black hole theories.
I hate the idea constantly proposed that traveling faster than light lets you move backward in time. According to this theory, you would time travel by exceeding the speed of light, then traveling exactly the speed of light (or a marginal fraction off of it) back to your point of origin to enjoy that time travel because you would not change your timeframe. In reality, to me at least, it seems like it would be more like you see light which had been cast off from Earth from those years ago. You aren't actually traveling backward in time, just seeing it. Then traveling back to Earth, you'd get a light speed fast forward to "now".
People have brought up the atomic clock factor, how this time travel via speed/gravity has been proven in orbit, etc. There are still too many variables to account for that inaccuracy. Energy is added to the clock's mechanism during launch and orbit which can account for a time difference. Vibrations can ruin calibration. Etc. You could only convince me if two clocks were calibrated in space, then sent in different directions; one probe sent out to the outer edges of our solar system off of our planetary plane, the other sent to orbit our sun in a long and lazy orbit where it gets to experience gravitational hijinx over several years/decades. Only when the probes start reporting time differentials that aren't accounted for by red shift/blue shift would I agree. Otherwise, we're talking theory, and I believe the theory is wrong.
I recently watched terminator zero the animated series there apporach to time travel was intriguing.
Its explained that everytime someone goes back in time they create another universe as their presence in the past changes the timeline.
However what they do in the last does not change the future they are from as they are now in a separate universe.
Since its the terminator films the plot being Skynet killing John to save itself even if it succeeded in killing him it would only effect the other universe so skynet would still die in its universe so no real point in going back as it wont actually change your reality.
Not a physicist or engineer i just thought it was a cool idea for the show
Untrue ! You can see space expanding faster than light! Hubble's law!
Light is an electromagnetic oscillation. How can you have an oscillation without time? Oscillation is by definition change, change only happens overtime.
tachyons i found to be a interesting theory and especially when it comes to energy given infinite energy and imaginary mass i find to be a cool topic even if its like you know not entirely been proven and that we wouldn't be able to perceive them
could you do a reaction to the video "Breaking Physics Using Math" by MAKiT.
its similar to this one, but explores more concepts and breaking them using math.
also prevent yourself from dying implies, you have already died... but if were talking time travel what else is possible in that universe
I suppose Lord Kelvin had never held a bird?
At light-speed, not only would nothing be visible (light cannot move relative to you), but you would also 'immediately' crash into a wall.
You are traveling at a finite speed over zero time, you cannot slow down without external help.
If you were to travel faster than light somehow, you would crash into the wall before you started moving.
We fix the weirdness of this by moving the future self into the past, your endpoint becomes the present when you start moving, clamping velocity to lightspeed through negative time.
Doesn't special relativity mean that c is constant, whether you are stationary or moving at c? Even if you were at c and you measured the time it took light to travel, you would still measure it at 300,000km/s. That's my interpretation of it, though practically it makes no sense but I am not a physicist.
What you think when I say "time travel" isn't possible. We can make it look kind of possible with numbers and letters because we have a limited understanding of the universe and physics.
People put WAAAAAY too much emphasis on Einstein's special relativity, wherein the "special" part is that is isn't based in reality. Yet almost no one consistently puts emphasis on his ACTUAL theory of relativity, which is an expression of observable reality.
Since we live in reality, SPECIAL relativity is just science fiction, and it always was.
Einstein himself was the first to acknowledge this objective fact.
And yet we kinda live in the past all the time, since everything we see, well light takes a bit of time to hit our eyes, and then the signals to move around the body. So we never see things as they are right here and now in this very moment, always a bit in the past
4:05 you should clarify that the photons arent actually slowed down. the medium creates waves but phase shifted these ínterfere with the light making it apparently slower but not actually.
@T. Folse Nuclear Can you also make reaction videos for Rational Animations? That would be awesome!
But what if you could travel forwards in time until you find the people who invented the backwards time machine? (It's my favorite Futurama episode)
To travel backwards, you need to go faster than light, which somehow is impossible. The universe will stretch space, co tract time, all just so that you're not faster than light from any perspective
Yeah but space can move faster than light.
@@borttorbbq2556 the universe expands faster than light or rather two points given they're far away enough that light doesn't reach to travel from one to another before the distance increases is a concept I don't understand, but it does make sense to have an observer Al universe, since we can only see stuff light is fast enough to travel from and reach us
The time reverse of fusion is fission.
If causality isnt correct who is to say going backward through time would even rewind it the same way on that path
4:20 AHHHH 😭😭😭 I HATE THOSE THINGS! nuclear spent fuel tanks are horrifying
This gotta be a troll 😂
The inaccuracies in these videos are astounding.
At 3:50, the video shows a photon moving in a flat plane across the space axis (because it's moving at C). That is wholly incorrect.
All paths of light in a space/time graph move at 45° angles as that is the only way to equate different inertial reference frames to eachother.
"Time" is at a stop for photons because of that 45° angle. It's distance traveled along the space axis is exactly equal to its progression up the time axis.
Also, the second law of thermodynamics is so poorly understood by most.
It clearly references entropy in a CLOSED system which rarely exists in our universe. Those laws were created through thought experiments to describe outcomes within the parameters outlined.
The other law that gets severely misunderstood is the first law, conservation of energy. It was created with very minimal understanding at the time. It only takes in to account the energy that was know of at the time, with no accounting for vacuum energy and quantum fluctuations.
There needs to be a concerted event to rewrite these laws to incorporate evolving knowledge instead of pushing these "laws" as hard limits.
The laws don't have to be rewritten. The problem is lack of communication (or even agreement lol) on what a scientific law actually is.
You're right if we were talking about a spacetime diagram (which is 2d, space and time dimension), but what they are showing is something strange 3d. I have no idea what they are trying to do here...
Also incorrect the second law of thermodynamics is not talking about a closed system it's talking about an isolated system. A closed system is different from a isolated system, although a lot of people will get it mixed up or just use the terms interchangeably
@bsadewitz true, maybe not "rewritten", just a better understanding of the actuality of current knowledge explained.
@ariantes221 in terms of "space and time", 2d is sufficient to quantify the result since the "space" axis incorporates the 3 dimensions of space and the diagram doesn't change regardless of which direction in space the reference frame takes i.e. going up or left or forward or down etc through space won't change the outcome.
This same diagram CAN be drawn 3 dimensionally and should actually always be thought of in that sense.
Well if all this AI turns into Skynet but no time travel I wonder how that will end up.
Marty Mcfly is also mad...
(I think just about all of this is HIGHLY speculative and SC-FI at best) but let’s remember powered flight was science fiction only 124 years ago, traveling to space or the moon the same. Take a cell phone back 200 years that’s well within 2-4 generations with good genetics, and you are a sorcerer or a witch. Which is why physics and the cosmos is so infatuating. I believe will will learn and see stuff at some point that would be to our modern life equal to magic.
9:58 home sour home
3:30 Changing time dimension speed is completely wrong in this context, your velocity away from other spacetime events delays observation of photons coming from the events but speeds up any photons come of from events in front of your geodesic
And yeah, a causal principle is just a way to state the physical content that is independent of representation with regard to what would be real in a world like that proposed by the principle, like any other physical content. Its useful but not objectively true in the same way a fact is, like whether a measurment comes out a certain way, which is independent of representation. A causal structure that by construction picks out a frame for simultaneity is perfectly fine and doesn't conflict witb special relativity at all, and could serve as the definition of what goes forward or backwards conceptually, as an organising piece of contents physically, and our conversations that are important for word only could map naturally onto thst structure in a way that allows no macroscopic time travel, only time travel by convention. Its something like everu degruof freedom having a physical feature that gets bigger with time for example, like the counting of a digital clock or the aging of a person, bssed of physics content alone, then there is an objective fact about time traveluwitb respect to such macroscopic concepts of change, time travel cant be a consequence of something fundamental like trajectory, it would have to be something like ending up with a loop where some stuff changes lile age along tje entire loop, and then its only time travel relationally, fundamentally there are no such coherent concepts, just conventions of description. If you want something approximately like an objective answer to whether time is traversable then its only coherent with respect to such relations, and every oart of a physical theory appart from coordinates or representation must be relationally defined for that to make much sense, only the macroscopic relational concept of time evolution is meaningful like i said a million times in different ways already because i fear i have not made myself quite clear. You are totally right to think about the principle of causality, but that is a relational concept really which needs a mechanism that is more or less macroscopic through and through to avoid the pitfalls of convention beyond tirvial representation. Basically for the concept of time evolution to be something more than a parameterisation of some mathematical functions it must be just macroscopic in a sense, it has to je a pattern without any fundamental description, which means that mathematics strictly speaking cannot account for causation and time evolution in a faithful way. This is somewhat hard to force you to buy into, but its also simple, its still just a pattern, but within it, forward and backwards is just defined by the pattern, tje pattern is defined by itself, and there is no fundamental entities other than the whole, even witj infinite densifuof detail, it is not possible to write down the mathematical forms for this exactly, and it doesn't solve the problem by not needed to be labled with coordinates and given representation, rather it is obvious that any physical content what so ever is encoded in itself we no longer have ti think about what it means fir a function to be a physical law, or a time parameter to be physicsal, time is simply just a pattern of relations that unforlds in the pattern its a tranformer of itself for space and time, just an answer to what exists, plain and simple, independent of space and time any part of it is related in a way where you could do something like analytic continuation from one part, no matter how small a subset to the whole, the only problem is that the mathematics doesn't exist and cannot exist to describe it at uts own level of detail, only abstract properties can be described not the object itself. And the relevance might be confusing to you, it doesn't seem to solve these issues, but the kicker is that any physical theory has these properties as well, its just not enshrined in our representations because treat content differently from law, when that is just a fallacy concocted by the human brain, fir no reason traceable by man other tha mistsken desires for our project to be more coherent than it is, mostly because of a misconception about method, it just because it feels right ti say that theory is predictive only if if doesn't get defined by what happens, like an account of how your day went rather than laws of how a nuclear engineer eats dinner. The reason is that we think its related to how predictive a theory is, but this is wrong, a theory by decree of physical content is more predictive than a physical law that describes the form of correlations within it, this is obvious whennwe out it like that, a physical law is just a way to group many theories by decree by the form of correlation in its content, if the law as defined by tje content in a tjeory like i described then the choices become one, and any such theory is completely unique in content and law, andnthe world could only given its state converge on a unique theory like that as long as we don't run into imperical limits, therefore by virtue of uniqueness of existence as a property, if sucj a theory is true, it is unquiqe innits existence as well, whether we can know what it is or not. Anyway this one was a bit crazier, but still true, and statements such as time is running this way or that by convention in sucj a theory, is a obviously meaningless statement outside just relations in the pattern as a whole, whether time travel exists is simply a question of features existing or not. Things like the grandfather paradox also just a feature of content, if its real, then if you kill your own grandpa it cannot lead bsck to your death stopling your actions, but maybe in a different dimension of time evolution that looks identical to you, that emerges as a copy of part of the pattern inside itself evolving after than point in a different direction even if it looked identical, again this entire thing could be described as only forward time evolution with no fundamental travel. As you said, in a different branch. But at the end of the day just correlated physical content.
wait but if everything is moving through time at the same speed it means that if you went back in time then there would be nothing right ? everything is in the present
@0:09 so thats how u pronounce it.. thank u for that
this sounds so cool and interesting, but my adhd ass brain can't understand anything😭
It'd be super cool if there were 3 dimensions of time like there were 3 of space
Observable time, relative time and Liminal time.
Observable time is what we see passing.
Relative time is Observable Time from another perspective in space.
Liminal Time is the difference between Observable and Relative Time measured.
I do not believe in anything stating that you can go backward in time. There is literally nothing to go back to. The past doesn't exist once time passes. It is gone. Time goes in one singular direction. anything else is nonsense.
actually the speed of light isn
t reduce it is defracted making it take alonger joury and its is still in that longer journey gpoing at the speed of light. So its only relatively slower than light. No light is both wave an [article modern physucs has relized this it rue for all objects particles and waves are basiclly defiing diffrent aspects of the same object.
if you go faster, you reach end of the universe faster, right? so I think if you move "faster" than light, you just crash into the "end". XD
Mr Folse, please react to Kurzgesagt's video about red dwarfs like you did with the white dwarfs before
Sorry for typos. Lol
Funny how you're both making a lot of simplifying assumptions, but the specific simplifications you make don't really overlap very much
Keep in mind: there is no way to transition from superluminal to subluminal speed, just like there is no way to transition from subluminal to superluminal, so normal matter cannot be sent back in time. Similarly, if tachyons exist, they are detected before they are emitted; if you emit one and it is detected in the past, then it was already detected, and you have not actually altered the past. If a tachyon was never detected, then the one you emit will not have been detected. We have never detected a tachyon, so we know for certain that no message will ever be successfully be sent back in time to 2024, and there will be no paradoxes (yet). This does not necessarily preclude sending information back in time, if tachyons can exist; however, if they do exist, they likely do not interact with particles whose mass does not have an imaginary component. They likely would be created in tachyon-antitachyon pairs with conjugate mass, and only interact with other tachyons or by annihilating with antitachyons.
It goes like this: you go so fast you trip, you are not running anymore, what is the opposite of running? Backwards! So now you are moving backwards in time, the inverse of moving forward, and now you can just go to the past!
IS LITERALLY THAT EASY! I DON'T KNOW WHAT ALL THE PHYSICIST ARE COMPLAINING ABOUT!!!
If you say light moves through water at about 2/3c, does that mean nothing can ever go faster through water than 2/3c? Maybe you can go faster than 2/3c through water if you deliver energy from beyond the water to this moving object.
you can go faster than the literal speed at which photons move through some sort of medium like water, the blue radiation picture he showed when he mentioned that is an actual example of this happening.
the Speed of Light, c (2.999...*10^8 m/s), is a universal constant, and can never change. Nor can something move faster than c. calling it the speed of light is just a name, it's the speed at which any massless particle moves at.
it would require more energy, than the whole universe contains, to travel back in time ^^
Would be possible to gain the energy just not within our universe. But that would take heaps of knowledge and for people to figure that out we would be a different evolved species by then probs lol
you would have to restore the state the universe was in... to do that you would have to bring every single atom, every single electron and quantum particle into the state it was in at the time you want to travel to... of course you would need more energy than the universe contains... you just can't move anything without using energy... I mean.... if you want to move all the energy in the universe... where would the energy to move it come from?... bottom line... I would disagree...
@katchou1337 it's a higher demotion problem that we don't understand yet. The answer could be in where gravity works if that's a higher dimension problem. We're not the centre of the universe why would we be the centre of reality? Lol. We've been wrong about alot of things in science and may even be less of the energy of our universe to do it. But you wouldn't need to replace the universe just need it intact still. If you only think within our universe it can be very limiting. There's a new theory of how our universe began like a universe colidding with another and forming the matter we know now
@@486veR ...u missed my point... xD
Short story shorter, the moral of the story is, we tesch special relativity in a dumb way, as a result even physics get this stuff completely wrong when discussing FTL travel, coordinates and representation os irrelevant to ordering in time only local causal ordering, what precedes what causally defines ordering in time and therefore time travel is only dedined by a reversal in the local causal ordering that cannlead to loops special relativity or general relativity neither bars such things or predicts it, to any degree stronger than Newtonian mechanic does, read the long comment, but essentially if you want to have it you have to without exception out it into the local dynamically defined causal ordering by hand, and claims to the contrary, are claims that coordinates have physical meaning or that choice of representation have physical meaning and thats simply a misconception about physics. Prominent professors make this mistake because they are quite frankly a bit weak mathematically and doesn't get the point of relational physics, where the dynamical relationships that are independent of coordinates define everything that is real in the physics. This is the original motivation for special and general relativity and they get it wrong, Einstein was also a bit wrong about it, but thats another matter, he was considering a theory of dynamical relations where nothing moves faster than light anyway and so, from that perspective the errors related to abuse of coordinates and time travel just dont come up, because the causal structure that defines the local ordering is the fastest thkng around, that means the local ordering cannot be messed uo by hand by abusing coordinate transformations such that you put it in by hand thinking that its the theory that is doing it for you, while you are just innocently doing positive velocities faster than light in different references frames, but its nonsense, they out it in by hand. Incan do that in newton look, the trajectory of a ball in Newtonian spacetime is a circle that loops back on itself in the time dimensions, i just derives time travel as a consequence of absolute soace and time, well, no i didnt, what i did do is draw a circle in a diagram and point to it, the people who think time travel is a consequence of special relativity and faster than light motion are doing the exact same thing, only doing a bunch of coordinate transformations while doing it, basically drawing a circle on a canvas while deforming it, thats still just putting it in by hand, and the people who think otherwise should go study harder maybe, because they are making trivial errors.
Welp, engineers only analyze using what they know. Unlike them, Physicists usually think these through. So your engineering opinion is rejected😅
I know you Know this, but as you said, so far they haven't, they already made a huge mistake of saying sum instead of the sum of squares under a square root but okey. Straight out of the gate they said something completely wrong. And i wont even attempt to comment further on this video, because why would i, its just going to be wrong in all sorts of ways, i'm usually in that headspace about professors getting special relativity wrong as well, because they do, and the way it is taught is also mostly wrong, they teach one type representation of the underlying physics in special relativity, as if its a unique theory, when its not, Einstein made the same mistake to be fair, its not like this is new to the literature or anything like that, it was mostly worled it before Einstein was even writing the first special relativity paper, and then he made somw bad choices lets say, but the theory he produced is the simplest to use representation of the physics, but the convention like i told you before on a veratasium video, that he used, is arbitrary and leads to a mistaken view of what the theory says if you thinknthe postulate about the one way speed of light is physical and not a matter if representation. But thats okey, the resulting theory can be used for calculation without error so its not a problem to work with it, but it is like thinking long division is why division works or that long division is a oart of how division is defined, which is just plain nonsense.
react to "World's Only GLASS Nuclear Reactor!" from Kyle Hill please
In this backward to the future paradoxy plain of existing, how woulda coulda it change the opportunity for nuclear science?
Hi
Oh, I'm a computer engineer and I was just offered a job with the military working nuclear. Do you think I should consider it or should I just not respond?
idk
also, speaking as a physicist who studied things like general and special relativity, it shows you're an engineer?
Time can nearly stop, all the rest is just bs.