Well really that was more relativistic, you looked like you had negative money, but actually you were just looking at someone else's money which you now had to pay them back but you had zero money, just like negative velocity this is all perspective.
Yes. It's called an overdrawn bank account. It's when You take out more money from You're bank account than what You have in it. Not a good experience at all. Sorry to hear that happened to You Spoiler Alert.
The "stealing negative cookies" example makes me imagine someone actually getting charged with a crime for giving someone a gift. "You're under arrest for stealing negative one cookies from this man" - "I gave him a cookie, I didn't steal anything!" - "that's a confession!"
It often triggers me how in some countries confession counts even close to one bit of 100 bits of evidence. Oh, except taxation, one has to proof taxman is wrong of course. Already proved effect-cause backwards go can ! So, make a tea-party of lawyers, mathematicians and taxmen, they're bound to find way to cheat reality. SEE ? They already did it, now they're semi-respected almost human beings !
@@a-blivvy-yus cookies are a string of text that tells the website "hey, i'm me!". when you steal it, you can post scam videos, get someone banned, steal their money, or even edit their esolang pages!
@@henrytjernlund Well sure, but the point is that just because you can make some assumptions that define a pretty-looking equation that solves your issues doesn't mean it will line up with experimental results. After decades of string theory stagnating, I think it's far more important for a theory to make testable predictions than for it to have elegant looking equations.
@@outlawscar3328 Agreed. But if some work of math results is a structure (Standard Model) which is similar what is in reality then that seems worth looking into deeper. And what about a null result. Such as a theory predicting no new Fermions and experiments failing to find any new Fermions.
@@henrytjernlund isn't there some joke about mathematicians trying to invent some useless maths but every time they do some scientists somewhere finds a use for it?
19:40 A "negative twenty dollar bill" is called a "promissory note". As far as being issued by the federal government, those would be "bonds". T-bills exist.
I thought the same thing exact thing, but then realized those aren't actually negative-Jacksons. A promissory note is a positive bill for negative dollars. Money itself is also imaginary (and mathematically useful) - there is no such physical object as a 'dollar' only 'dollar bills' or 'dollar coins' and so on.
Also the fact that US Federal Reserve Notes are debt. I owe you $20s in REAL goods and services, so I give you a $20 bill representing my debt, the bill itself isn't really worth much besides a bit of denim and cotton. On the Micro level, it's just passing debt (negative value) around in circles while at the Macro level the Fed tries to pay off those same debts with more debt, pushes into existence even more of those near worthless bills devaluing those little debt contracts that already exist and just running this little game around and around. Who or what is actually putting value in this system and paying the debt? Who the hell knows. The entire world economy is built on imaginary numbers. Really, Isaac shouldn't have brought up money as an example of real numbers, if anything it's proof that trying to compound a negative value is nonsensical and doomed to failure.
when you give someone a $20, you have negative $20 in your wallet. Does your wallet have a negative $20 bill? Sure, because it was in your wallet at some time and now it's gone - you can't see the negative $20, but know it's there.
Yes, a negative $20 can be represented as anything, as others said goods and stuff, but it's not a true negative $20 bill. It's a representation. It's like drawing a $20 bill on a board - that's not real - it's a representation that makes you feel the value on that board is $20 when it's not.
@@extropiantranshuman There is no need for a negative $20 bill b/c debt is already a negative value. The bill is the representation of that negative value (called debt) that's exchanged for things of real, positive value (goods and services). If we had such a thing as a -$20 bill, it'd actually be a double negative. We don't think of fiat currency as debt, but it goes back around to the premise of currency in the first place. My days labor could be traded for an ounce of silver, which in of itself is valuable, that I could then in turn trade to the fishmonger for a fresh fish and a baker for a fresh loaf of bread. We replaced that small medium of trade passing hands with something that is not intrinsically valuable in any meaningful way. The 'Federal Reserve Note' is instead backed entirely on 'faith' (fiat) in a quasi-governmental institution. These bills are a debt contract with the US government, they guarantee that my $20 bill will hold the value of $20s. Rather than the transaction simply ending when I trade my silver to the baker or fishmonger, those merchants now take on my contract with the US government and assume the value of the debt they owed me. The bill is a contract owed (but only theoretically payable) to the bearer. Fiat is debt traded around and around. Debt is in of itself negative value. Economics is a really convoluted and counter-intuitive field, I fully empathize with that, lol.
Sometimes people will acknowledge the comment wasn't theirs initially, but I guess there's a big chance you'll get away with the plagiarism - and there's no consequences if you don't
@Portal Opener Time is relative depending on location so if you sent a signal to someone FTL who had a relative time to yours two seconds slower then you, you would infact talking with them in the past breaking causality and creating a paradox therefore it is impossible.
Could the logical problem of FTL making the fermi paradox so much worse in a scifi setting be avoided, if the propolsion method requires some sort of infrastructure at the destination, like both ends of a womhole needing to be constructed at one place and then seperated at sublight speeds?
Five minutes in: "Voids of existence are appearing at random all over the shop from nowhere in particular." Well then. "Tachyons cheat reality by being a particle that exists on the other side of the light-speed barrier" OH SHIT I'M FEELING IT.
@@specter86fl Just remember that a photon can be created out of the blaze of the first star, bounce around for millions of years inside of that star before eventually escaping, then spend billions of years travelling through space and time to reach the earth only to eventually help some weirdo tan their asshole. and in all of that time none passed for them.
@@specter86fl Preferrably, say, an IMDB link or something, or at least a description of "the one directed by this person with this other person as the lead".
Hopefully, one day we are able to create the ability for FTL. For now we'll just have to stick to sci-fi, and its ability to travel at the speed of plot.
but with scientists being used as political pawns nowadays...same with some doctors (looking at you fauchi) i dont see it happening nearly as fast as i would mere years ago.
@@romanplays1 I will give you the benefit of the doubt and assume you are referring to how science was delayed hamstringed and kneecapped by politics and stupidity. Or like the clusterfuck that is SLS, or with scientists being used as pawns to promote stupid shit like lead in the air is fine or climate extremification isn't real.
@@Alex_Barbosa COVID or not, if you think that scientists can't be bought as easily as politicians then you are foolish. Scientists are human and are not infalliable.
@@housetheunstoppablessed4846 a single scientist can, but believe it or not, the scientific field is not the most lucrative. People go into the field because they are passionate and want to learn and use that knowledge to improve humanity. They are not in it for the money because money simply isn't that high or consistent in the field. And scientific research and development is peer reviewed. Meaning no one person or small group of people can make decisions on what is or isn't scientific fact. It takes the entire scientific community to review and test each other for their flaws. Everything is always in question and open to being changed for better results. Basically what I'm saying is you can't buy the entire scientific community because the majority are not in the field for money and taking bribes to lie about their research would be antithetical to their chosen path in life. It's ok to be skeptical, that's what science is, but at some point you have to trust the people who have given their lives to becoming experts in their field, because if we don't, then the entire foundation of all technical fields falls apart. We can't be experts about everything so we have to trust each others word when it comes to topics that they're more proficient in than us.
Oh man, I'd love to be newly discovering Isaac! This man has given me many hours of enjoyment, expanded my understanding of the universe, and improved my critical thinking skills.
The best way to explain why math says things and reality says no is that we made math up (and I should note that this is one view of math, there are others). In this view, math is a fiction that happens to be very useful when analyzing reality, but it is just that: Fiction. PBS Idea Channel did a good video about this, but the reason math is this way is the same reason that language is this way - we made both of them up, and they're totally arbitrary. If we had a better way to analyze the nature of reality than mathematics, we would use that instead.
Of course, one of the other major views of math is that it's discovered, not invented. At any rate, math doesn't care if the numbers you plug into an equation that models a phenomenon are physically possible, or even meaningful. You can still crunch the numbers and get a result.
I believe that math is objective. However, all currently known physical equations are approximations, and we do not know if the approximations break down under certain conditions. For example, the equations of Newtonian physics say that any arbitrarily high velocity can be achieved by a applying a sufficient amount of kinetic energy to an object. We know that the current relativity is an approximation because it can not explain quantum effects. Or more generally, we know that all of physics in an approximation because research is still going on in that field.
Your early episodes are superb, Isaac. They are where I started and got me hooked, not only on this channel, but on science and futurism RUclips. Don't hush the early stuff up!
Nothing can exceed the SoL Space can expand faster than the SoL Space is "nothing". Zero mass. So to get to infinity and beyond, Buzz Lightyear needs to go on a diet.
@@singularitysquaredllc.895 Indeed, and that's not what he said. The air quotes and subsequent clarification weren't there for aesthetic, the use of the word nothing, however, was. He chose it for the appeal of symmetry.
mathematically there is no way do define infinity. as its name defines it says no end defined. still its not being defined is not a proof of it doesnt have an end. its just defines the point of end is far beyond reachable limits. but no technical or mathematical definition that it will not end. :D you need infine charge to reach to infinite. wich means you have to charge infinite time. and as you start from 1 :D ...
So then instead of designing our ships to travel at the speed of light, we need to design ships that travel at the speed of SPACE! Brilliant, problem solved, just make an engine that runs on space
I mean, if a ship could delete the space between it and it's destination, that'd technically work. You probably need a PhD to describe what that would look like if it passed next to you though.
@Portal Opener You would be a great techno babel writer as a science fiction author, it's too bad that you waste your potential on being a moron on the internet. go write a Sci Fi book, i'm sure it would be cool if you put this much effort into it.
There was a recent study that found that by using certain geometry we can create a warp bubble with normal matter, it'll take a Jupiter's mass worth of energy so it's still not very plausible but better than negative matter.
I heard something like that as well, but the problem is still accelerating the bubble you created to above the speed of light, which is still impossible.
@@gammarayneutrino8413 But exactly maybe not. Does empty space itself have mass? The bubble may not have a speed limit. The bubble might isolate what's inside to the space outside. When I write my own science fiction I look for plausibility, that's all. If you are going to exclude FTL from all stories then you're going to have a lot of limited freaking boring stories.
In a physics FB group I joined a discussion asking of space-time. can move. Someone said yes. not sure what that would mean or be like but maybe in a super-fluid sort of way the motion might be effectively friction-less. What do we really know about space-time and it's properties. Do we even know if it is Euclidean, spherical, hyperbolic, or something else we haven't figured out yet.
You are very informative and always have excellent visuals. I honestly don't know how you aren't more in the spotlight. More people need to watch you and soak up these information packed videos. Thanks for all the journeys you have taken me on so far Mr. Arthur!
I'd like to mention, the Chronology Protection Conjecture isn't the only response to time travel paradoxes that could be caused by FTL. There are other conjectures as well which I believe stand on the same footing. - Cosmic Censorship: If something reaches into the past it cannot affect it due to being behind an event horizon. No interaction no problem. - Consistency Principle: Same as before but if something goes into the past it cannot alter the course of the events in a way that would prevent the cause from generating the effect even in the case of inverted causality. - Parallel Universe: Similar to the one above but essentially when there is something travelling back in time the universe essentially splits at the quantum level, relegating the altered timeline to another universe, essentially turning the closed timelike curve into a spiral And finally, I'd add that Miguel Alcubierre expressed concern about the CPC however he also mentioned that it wouldn't disallow FTL perse but rather that it would make it impossible to use FTL to make a time machine. What do you think?
Isaac, your early shows are really great. I've been a big fan since you started doing regular episodes and frequently go back to watch some of the earlier videos. I'd hate to see them go or be replaced:( sure the production value is better now, but many of us wouldn't be here if it weren't for those early videos. after all the primary ingredient here is hearing the concepts discussed, elaborated, and expanded upon rather than the eye candy...but the eye candy helps. drink in 1 hand, snack in other:) keep up the great work!
Fair point, and the usual top 3 scifi novels on polls, Fouindation, Dune, and Ender's Game are all critically dependent on 3 massive plotholes but are still great [Psychohistory, water shortages for interstellar empires, children as strategic geniuses for anyone wondering]
If a country created a film studio complex with an excess of plots, then you could run a cable to Hollywood where there are major plot holes and create a giant battery. Such a literary potential difference could power the world!
Well, you go ahead and write a popular SF series where it takes most of a characters life to get to just one place. Each main character of the book/movie may have to be a descendant of the previous and do new world building every time. See how well that goes.
The laser point moving across the surface of Mars "faster than light" is a concept that I'm sure, if I could fully wrap my mind around, would really help me understand this subject. I kind of get it, I think. The point may go from one side of Mars to the other faster than light, but from the perspective of the point, no info goes directly from one local to the other, all info moves through the source of the laser and back to Mars, at the speed of causality. Am I thinking about this correctly?
The photons have a speed, being fast enough to take minutes to get to mars. You can flick the laser to point at different areas of mars very quickly, changing your angle really quickly. Then that gets multiplied over a large distance until your "point" is traveling "ftl" in terms of distance between when it was still and when you moved it. But the effects still only happen at light speed, the laser flies to mars at that speed. One can almost imagine the laser like a water hose, you can flick a water hose to point to a new spot quickly, but the water still takes the normal time to get to the targeted location.
So... A whacky idea here. 1. FTL is not possible because it would break causality. 2. galaxies are moving away from us faster than light and do not interact with us. There is no causality between us and them. 3. How about an FTL drive that goes from here to one of those galaxies that are no longer in a causality loop with us? A drive that works on ridiculous distances but not up close. Doesn't sound like it should break anything.
i feel like i just fell for a trap. i came to this video because i wanted to know more about FTL and how to achieve it one day, but i've left not only convinced that we won't, but that it's good that we can't. Isaac, you cheeky sausage, you.
I'm sure most of us are familiar with the idea that space/time, but this video and the way you reframed the concept so thoroughly and articulately, might very well be the first time the concept really made it 'click' and make sense to me, beyond just being able to repeat the law. Very well done!
I think the hardest clue that “Light Speed” is an unbreakable upper limit is E=MC2. WHY should the energy of mass be a multiple of C??? But somehow it is .. woven right into the fabric.
Not only absence of FTL prevents Earth colonization, but inability to break FTL is actually the main reason why this Universe exists. When only causal Universes can meaningfully exist, it automatically implies at least rudimentary logic for this Universe. That's why logic is the king.
But the presumptive impossibility of FTL will NOT prevent colonization. It will just make it a slower process, in which there is no real-time communication between the frontiers and the original star system. Conceivably, Tellurian (earth-origin) life could spread through a wide region of space, even beyond the Galaxy, without FTL.
@@oldionus Yeah, but it prevents colonization from not only other galaxies, but also from beyond observable Universe. It reduces chance to possibly surrounding star systems, Milky Way or if we stretch it from Andromeda, but prevents basically the rest of the Universe. That's a big reduction.
another thought though this is the sci-fi writer in me spinning something out. speed of causality gave me an interesting idea for a potential limit on minimal distance that can be traveled by FTL, it could be that you can actually arrive before you leave in objective time but you cannot be perceived arriving by an observer at your starting point. the light from your arrival at a distant star has to arrive at the your starting point sometime after you left to maintain causality or be so far away that the starting point cannot observe the end point do to universal expansion. of course that would make it imposable to go a light year away by FTL but easer to go to the edge of the universe where things have already moved beyond where the light can reach us.
Getting to your destination faster than light would mean the light indicating your arrival would by definition arrive after you left, whether you travel 1m or 1lyr. Its you who are traveling faster than light not the light itself.
There's been some suggestion on atomic rockets that quantum effects could destructively interfere with time travel. or at least paradox's. So a drive might work as long as no paradox's where created, and might self destruct if used in a way that would cause one.
@@voteindependentforindepend7181 I was referring to the speed of causality and traveling faster than it would by definition be time travel. Meaning that you arrive before you leave in objective time. Which would violate causality. To preserve causality and prevent paradox, traveling beyond the point where you can be observed could be a solution. If you go ten lightyears as a speed that results in you arriving 20 years before you leave then the light from your arrival would show up ten years before you leave. This is the causal relationship I'm suggesting needs to be avoided. So if you can only go at that speed you have to go to a point beyond 20 light years to maintain perceived causality.
@@spacepiratecaptainrush1237 but you dont arrive before you leave. Even if you're traveling at trillions of times the speed of light(causality, Isaac makes the distinction but they are effectively the same) your trip will just be extremely brief, depending on the distance travelled.
For non time travel related causality issues I am probably wrong because quantum physics is the realm of masochists but if i am on the earth and there is another guy on the moon one light second away and we are sending signals back and forth to for example argue about the laws of reality on youtube comment threads and I use some FTL method to send a signal to the moon in 0.1 seconds 10X faster than a standard speed of light transmission how does that violate causality? I write up my message, then I hit send, then an amount of time passes for both me and the recipient, and then the signal arrives. For it to violate causality wouldn't the recipient have to receive the message before I sent it? that would require it going there in negative time which would be faster than infinite velocity right? like if I have ftl that sends signals to a place one light year away I can send a radio signal and get a reply roughly two years later. if I have FTL radio signals that go 365X the speed of light and I send a signal one light year away on sunday the recipient should get it on monday and ill get a response on tuesday, how would that violate causality? Sure it would be faster than light but why is light necessarily going at the maximum speed of causality? for warp drives where you send a chunk of spacetime to some place else in less time than light would take that still takes time and still shouldn't violate causality. now, if you could send a signal to someone on sunday and they received it on saturday that would violate causality but the other ways I don't see how they violate causality. I personally find it way WAY *W A Y* harder to understand because rather than just "fast thingy gets heavier as you speed it up so it becomes slower thingy requiring more energy to make it a faster thingy each time" it instead relies on relativistic time and local time and time dilation and all that special relativity masochism stuff.
@@atashgallagher5139 I get what you mean, but that’s not how the video explains it. In the video, and if I’m understanding right, it says more or less that lightspeed it the maximum rate at which information can be exchanged. So of course, FTL wouldn’t go against causality as long as the result doesn’t occur before the cause. But once again, that’s not how the video uses the term causality here. “Speed of causality” is thus the maximum speed at which causality CAN occur. In that sense, FTL has some vague meaning but “faster than causality” absolutely doesn’ so it’s easier to see it as a limit.
11:22 Does what we call "spun" take energy that would have been used to go faster? Therefore the SoL is slightly slower than the maximum possible if there was no spin?
9:15 You made a mistake. Potential energy slows time, therefore time slows *near* black holes. The potential energy increases as you move *farther away* from the source of gravity. Thus, the potential energy's time dilation works in the opposite sign from what you said. Time slows near a black hole because of the curvature of spacetime.
It's the curvature of spacetime that slows time, not the potential energy. The potential energy is a result of the curvature as well, not the cause of it.
To be perfectly honest if we can figure out FTL travel it will be 1. Wormholes and/or Warp Drives using gravity or mass manipulation 2. Higher Dimensional Shortcuts like Hyperspace, Slipspace, Subspace, etc Also Mars is not several light years away but a few light minutes away Alpha Centauri is about 4 light years away
It`s such a shame that other educators and speakers don`t posses your skill of explaining difficult, non-intuitive concepts. You have made it easy for anyone to start to understand the concept of relativity. Very high respect from United Kingdom. Chris.
Intelligent and/or Alien Life may very well be common... And advanced Technological Alien Lifeform developing is probably a far rarer event in our Universe and I think most people do not understand the difference! We maybe the only Species to have developed Technology. Besides always remember the old Sci-Fi Movie quote, "To Serve Man, it's... it's a cookbook!"!
for all we know dolphins are smarter than us. but dolphins don't have opposable thumbs and they live under water so they can't develop tools and that makes us the only industrialized civilized species on earth. how do you melt metal to develop smithing to develop guns underwater? you can't, which is why dolphins haven't done shit and humans have a massive society.
21:20 Yes, I love how people say the warp ideas won't ever work because they still don't allow FTL speeds due to massive radiation doses, atomic impacts, or whatever, but even a barely-functional "warp drive" operating at a small percentage of lightspeed would open up the entire solar system to us, reducing the travel time to even the most distant planets and objects to days instead of years.
well we already have drives that can do that. light/beam sails & nuclear drives are the only ones i can think of off the top of my head & they allow speeds of multiple percents of c with the light sail being able to get arbitrarily close
@@virutech32 True... eventually. A light sail could eventually reach some % of c given years or decades of acceleration. Some versions of a nuclear drive could eventually reach that after expending a lot of fuel (nuclear drives are basically steamships, that steam still comes from fuel). An on-off warp drive does the same thing, only instantly. You don't even need to be going very fast at all when you hit the switch. And it solves the deceleration problem that light sails can't and other drives have with a deceleration time (and fuel) equal to their acceleration. Just sit in orbit until you're pointed roughly at Pluto, hit the switch, squish space in front of you so you make 0.01c and reach Pluto in 28 days. Flip the switch, and spend whatever fuel you need to achieve orbit. Granted its an oversimplification, but achieving that 1%c drive would make even our current rockets into interplanetary vehicles.
Theory: actually light speed limit is just enforced in certain areas of the galaxy where aliens has put in the speed limit to help protect primitive civilizations, outside of the Sol sphere of control (around 37 000 AU radius) relativity doesn't apply and linear acceleration is possible on objects up to any speed.
Nebula which is affiliated with curiosity stream which was founded by some of the original founders of discovery channel, so yeah, he basically does have a spot on discovery channel but without the overbearing corporate influence or the corporate budget.
@SoraNezumi 1/8th, but yeah. But going a second layer deeper, it'd be 1/64th you'd need to beat. Six layers in, you'd only need to beat 4118 kph (2559 mph) which is slower than our current jet speed world record, let alone spacecraft. If you had ten layers of phase space that worked on the same ratio as the nether, then you'd be ftl on the surface if you were walking at 1.006 kph (0.625 mph)
I think the universe is two counter rotating hyperdimensional black holes and the one we are in has an escape velocity of the speed of causality. Also the expansion is the pull of each black hole. The great attractor is the other black hole. At the end of time the black holes merge creating a huge burst of energy creating a new universe on the edge of it's event horizon. But really this already happened and it's just our limited perspective from being a part of it that gives us the illusion of time and space. Like how from a humans natural perspective the world is flat and stationary.
Would aliens even go upon the same technological route as us? I believe timing of ideas is very important when it comes to discovery. Would they even have someone who create math or measurement of distances using time? We use time as an measurement factor of reality but what if aliens biology allowed them to see a different perception upon to base their technology on that's probably more advanced then relativity descriptions. This allow factious energies to exist like Sprit Qi or Sources of energy from a folded universe/dimension or particle unseen due to lack measurement technology. It would logically make sense for strong aliens to create technologies based on FTI (Faster than information) we don't know of. Reality itself could simply be a specific type of perception of the change in a geometric dimension. Like Reality could be just a slice on a 10-dimensional cube and going FTI breaks you out that slice into a more variety of possibilities/ movement of energies that's more diverse than we know.
@@vincentcleaver1925 Kinda true, But I mostly enjoy his videos more than I agree with them, I do agree with a lot of his stuff, but I also disagree with other things He says, Plus I never said He is one of the Best Historians on RUclips.
Love the way you're thinking here. I subbed at about 25k subscribers way back in the day. A revisit of this would be awesome. :D You make FTL seem so naturally linked to quantum phenomena and relativity and this video is the first time I've actually understood the requirement of negative mass a requirement for the Alcubierre drive. Positive energy to contract space in front of a ship, negative energy to expand the space behind the ship. Mind blown again, thanks for this.
Outdated: there have been made a warp drive mathematical model that doesn't need negative energy. Regarding Quantum Entanglement - hasn't the "hidden variables" hypothesis have been proven to be wrong?
Imaginary is a bad name for those numbers, they're just as real as "real" numbers, the best way to think of them is not as a single number but a pair of numbers that are just the reverse of each other, so rather than `i5 * 5 = -25` it should be `i5 * i5 = -25` which in programming is equivalent to `r = i[0] * i[1]` or `r = i[r < 0] * i[r < 0]` so always think of imaginary numbers as square root pairs, this also implies an infinite number of number axis, not just "real" & "imaginary" but rather "n", "n[2]", "n[3]", etc, etc.
Honestly I think that in the future people will play full dive true to life quality VR games that are written, produced, and voiced in real time by AI as you play, you can then live in a simulation of a world or game as the story plays out around you with everything impacted by what you do. The flexibility of D&D ran by a human but the quality of a AAA videogame title and the immersion of direct nerve interface VR with the capacity to make decisions that you normally only have in a story when you yourself are the author. In fact you might get people playing games where they have their memories altered or blocked temporarily so that they think that everything is real or that they are someone as a character in the story. If you have some matrioshka brain AI god machine it would be no problem for it to manage writing a story, producing the world, simulating all of it, and basically being an actor for every single NPC in the game giving them all sapience in there quality of interaction but without creating people because it is just an AI controlling them not new synthetic people made just for your game. Then you can finally fulfill your dreams, or get a well written ending to mass effect 3 or an actually well made mass effect andromeda. I bet people will spend decades in single worlds / stories before moving on sometimes, and it will be way better than sitting around doing nothing on your couch in a giant mansion as an AI does every single job better than you ever could. And reality would get boring after the first few thousand years if everyone is trapped in the solar system and maybe the few nearest neighbors. But it is proven mathematically that the Alcubierre warp drive is possible without negative mass only using positive mass which makes it much more likely to be possible and as they work on it the energy needed goes down, so it could very well be that warp drives and FTL are possible just really hard.
Wow these are all basic concepts that I've know for well over a decade, but I feel like I know how they all actually work so much better now, your explanations were incredible.
I am still rooting for mass effect drives which are in a way a modified warp drive so I say someone should go nuke Charon a few times. but the Alcubierre warp drive is possible without negative mass using only positive mass, now how you would actually manage to do it is another question entirely, but theoretically it is possible to make an FTL warp drive using only positive mass.
So what you're really saying is that we should go send some mining equipment to Charon right away to do some exploratory digging and scanning for large metallic structures in the middle that are currently dormant but can be reactivated? That seems to be what is being suggested here.
When you break entanglement, you are still sending information. The "contents" or value are not as important as the fact that it has been broken. Think of "one if by land, two if by sea". The difference between 1 or 2 pairs being broken is information transmission.
@@TiredRoman The point is that the value is irrelevant. All that you need to know is whether the entanglement is broken. Take the letter analogy. You have some number of "entangled" letters on your desk. If you see one letter being "opened" on your end then you know that it was opened on the other. If you see two letters being opened, then again you know they opened two on the other end. The content of the letters is meaningless. You just have a pre-arranged agreement that opening one letter means one thing, and opening two letters means another. It is the number of broken pairs that conveys information.
@@TiredRoman Sure there is. The whole point of the entangled particles is that both are in a superpositioned state. As soon as you see that the particle on your side is no longer in a superpositioned state (ie it has some value, and it does not matter what that value is). then you know that the entanglement has been broken on the other side.
@@ravenlord4 if you "see" the particle then you have already broken the entanglement. You won't able to tell the difference between you inciting it breaking vs your partner doing it.
I think these discussions fall short logically, rather than mathematically. I'm no physicist, however I fail every time to understand how time and space are the same thing, and causality is tied to this concept. So I too separate causality from the idea of a speed limit. Say for instance that I live here, on Earth, and Betelgeuse has JUST exploded into a supernova. The speed of light dictates that I'll see that light only once it has reached me. But does that mean that the event hasn't occured? No, it just means that light has a distance to travel towards me. The conflation between time and space is not present here. Likewise, if I travel towards Betelgeuse, even at a lower speed than the speed of light I'll reach that light sooner than if I stayed on Earth. The causality is not violated here. Likewise traversing space over the speed limit does not in any way create a paradox, because the event HAS happened, the LIGHT merely hasn't reached me. It's like arguing that a supersonic jet emits no sound because you can't hear it yet. I just can't wrap my head around it and keep thinking it's solipsism on the part of the scientists. Maybe clearing THAT up will help people understand the underlying problems with FTL, or make the scientists realize they are perhaps talking about another SPACE dimension, not a time one. Lastly I'd like to point out that it is theoretically possible to eliminate the event horizon of a black hole with spin, without breaking lightspeed, which would also break causality (the naked singularity problem), so I guess we have no choice other than kugelblitzing a Black Hole into existance and immediately spinning it to open this pandora's box once and for all. Who knows? Maybe that's the Fermi Paradox explanation right there. Fusion Power > Overpowered Lasers > KugelBlitz > Unlocking the secrets of the cosmos > Death?
@John Smith Energy requirements does increase exponentially the closer you reach c however. Though I still think that is the work of another dimension causing this effect, rather than time itself. Don't have any proof, but it is an avenue I'd research, were I a physicist.
Learning that the speed of light and speed of gravity waves are the same speed of causality and neutrinos just a tad slower still was awe inspiring, and it those were fairly recent discoveries. Go science.
@John Smith Just stating that does not make it true. There was a experiment that confirmed that withing experimental sensitivity both the gravity wave and photon wave arrived at the same time at earth from some explosion far away. Im happy to change my thinking if other better data comes up, until that time Im going with the boring mainstream view. Do I want the speeds to be different ? Yes.
Stuff like this makes me wonder, why do we still measure speed in arbitrary units, like m/s or km/h? (not even mentioning other units. Looking at you, USA) We could measure speed in nc (Nano c) or pc (Piko c). That might remember humanity how irrelevant they are. And it could also shift the way we think from zero speed as absolute towards max speed as absolute.
around 21:20 i had some crazy nostalgia from when the professor (futurama) explains that his ship doesn't move in space but it moves the universe around it
Not having FTL makes stories involving interstellar states and entities boring... If would be impossible to communicate in any 'meaningful' time with others 500 light years away for example.
@@musafawundu6718 Holly hell, the aliens from alpha centauri have fired a missile into the UN headquarters, we must fire a return attack. Humans build a giant missile and launch it at alpha centauri. Ok boys, time to wait ten to twenty years to see if we won the war or if we need to send another return shot. or we get contacted by aliens in alpha centauri asking for us to communicate we send a response, and then then next eight years there is no response as we wait for them to gt ours and send one back. see, that could be interesting if your book took place over thousands or millions of generations.
...and the bartender said "we don't serve hypothetical faster-than-light particles here!"
A tachyon walks into a bar...
is it better to have theoretical bar tab, an imaginary bar tab or a hypothetical bar tab?
!ekoj a su llet , C luaPJ
@@bobologic6849 I'll take the negative bar tab. Everyone drink up!
Tachyon Lives Matter
Who better to raise the bar on speed of light thresholds than a Bartender?
The notion of negative cookies, well that really takes the biscuit.
DOES IT NOW?
I'm just waiting for the Negative cookies diet :)
Space is expanding and i don't think its by nature. Its because the tracking cookies are too delicious.
bruh
If you add a cookie to the jar, you have stolen -1 cookies 😜
Negative numbers do exist. I’ve had a negative balance in my checking account and the effects were very real.
Well really that was more relativistic, you looked like you had negative money, but actually you were just looking at someone else's money which you now had to pay them back but you had zero money, just like negative velocity this is all perspective.
@@atashgallagher5139 you must be fun at parties
Yes. It's called an overdrawn bank account. It's when You take out more money from You're bank account than what You have in it. Not a good experience at all. Sorry to hear that happened to You Spoiler Alert.
For what its worth I found your joke funny.
@@Mike-sp6tt you too
The "stealing negative cookies" example makes me imagine someone actually getting charged with a crime for giving someone a gift. "You're under arrest for stealing negative one cookies from this man" - "I gave him a cookie, I didn't steal anything!" - "that's a confession!"
It often triggers me how in some countries confession counts even close to one bit of 100 bits of evidence. Oh, except taxation, one has to proof taxman is wrong of course.
Already proved effect-cause backwards go can ! So, make a tea-party of lawyers, mathematicians and taxmen, they're bound to find way to cheat reality. SEE ? They already did it, now they're semi-respected almost human beings !
being put on a trial for stealing a cookie
@@official-obama Given how strict EU regulations are getting about them, it might happen sooner than you think!
...wait wrong cookies.
@@a-blivvy-yus cookies are a string of text that tells the website "hey, i'm me!". when you steal it, you can post scam videos, get someone banned, steal their money, or even edit their esolang pages!
@@official-obama That was the "wrong cookie" I was referencing in my reply to you, yes.
The speed of light is basically the universe's maximum refresh rate.
Planck time
Imagine if you could go faster than light - but it would cause lag and possibly freeze/crash reality.
@@jc441-i3q or you start lagging around through your ship and when you trip you might accidentally shoot into space like a buggy game
It does sometimes eerily feel that way
@@isaacarthurSFIA Hi Isaac!
That intro pun just took a few years off my life 🤣
Me too
Funny, it added years to mine.
Lol
Noted😂👌
This is the kind of joke that only works on this audience :)
“And again, just because it works in math doesn’t mean it does in reality.”
Isaac Arthur
I'm starting to suspect the opposite. That things work in reality only because they do work in math. That math made the universe what it is.
@@henrytjernlund I've had my suspicions as well lol. It's just fucked up enough to be true.
@@henrytjernlund Well sure, but the point is that just because you can make some assumptions that define a pretty-looking equation that solves your issues doesn't mean it will line up with experimental results. After decades of string theory stagnating, I think it's far more important for a theory to make testable predictions than for it to have elegant looking equations.
@@outlawscar3328 Agreed. But if some work of math results is a structure (Standard Model) which is similar what is in reality then that seems worth looking into deeper. And what about a null result. Such as a theory predicting no new Fermions and experiments failing to find any new Fermions.
@@henrytjernlund isn't there some joke about mathematicians trying to invent some useless maths but every time they do some scientists somewhere finds a use for it?
“You cant go faster than the speed of light!”
“Of course not. That's why scientists increased the speed of light in 2208.”
Futurama!!?
indeed they will. But in 2028, not 2208. They'll find a way to reduce permeability to zero, or even make it negative.
Best update patch ever
They probably won't!
Lmao 🤣🤣😆😆😆😆😆
19:40 A "negative twenty dollar bill" is called a "promissory note". As far as being issued by the federal government, those would be "bonds". T-bills exist.
I thought the same thing exact thing, but then realized those aren't actually negative-Jacksons. A promissory note is a positive bill for negative dollars. Money itself is also imaginary (and mathematically useful) - there is no such physical object as a 'dollar' only 'dollar bills' or 'dollar coins' and so on.
Also the fact that US Federal Reserve Notes are debt. I owe you $20s in REAL goods and services, so I give you a $20 bill representing my debt, the bill itself isn't really worth much besides a bit of denim and cotton. On the Micro level, it's just passing debt (negative value) around in circles while at the Macro level the Fed tries to pay off those same debts with more debt, pushes into existence even more of those near worthless bills devaluing those little debt contracts that already exist and just running this little game around and around. Who or what is actually putting value in this system and paying the debt? Who the hell knows. The entire world economy is built on imaginary numbers. Really, Isaac shouldn't have brought up money as an example of real numbers, if anything it's proof that trying to compound a negative value is nonsensical and doomed to failure.
when you give someone a $20, you have negative $20 in your wallet. Does your wallet have a negative $20 bill? Sure, because it was in your wallet at some time and now it's gone - you can't see the negative $20, but know it's there.
Yes, a negative $20 can be represented as anything, as others said goods and stuff, but it's not a true negative $20 bill. It's a representation. It's like drawing a $20 bill on a board - that's not real - it's a representation that makes you feel the value on that board is $20 when it's not.
@@extropiantranshuman There is no need for a negative $20 bill b/c debt is already a negative value. The bill is the representation of that negative value (called debt) that's exchanged for things of real, positive value (goods and services). If we had such a thing as a -$20 bill, it'd actually be a double negative. We don't think of fiat currency as debt, but it goes back around to the premise of currency in the first place. My days labor could be traded for an ounce of silver, which in of itself is valuable, that I could then in turn trade to the fishmonger for a fresh fish and a baker for a fresh loaf of bread. We replaced that small medium of trade passing hands with something that is not intrinsically valuable in any meaningful way. The 'Federal Reserve Note' is instead backed entirely on 'faith' (fiat) in a quasi-governmental institution. These bills are a debt contract with the US government, they guarantee that my $20 bill will hold the value of $20s. Rather than the transaction simply ending when I trade my silver to the baker or fishmonger, those merchants now take on my contract with the US government and assume the value of the debt they owed me. The bill is a contract owed (but only theoretically payable) to the bearer. Fiat is debt traded around and around. Debt is in of itself negative value. Economics is a really convoluted and counter-intuitive field, I fully empathize with that, lol.
The bartender said, "We don't serve faster-than-light particles here."
A tachyon walks into a bar.
Oh this is copied, thought it was an original
That must have really hurt, especially at that speed.
Sometimes people will acknowledge the comment wasn't theirs initially, but I guess there's a big chance you'll get away with the plagiarism - and there's no consequences if you don't
@@ctakitimu The other one was copied, this one just arrived later
"Thou shalt not violate causality within my historic light cone ... or else!" -TheBigE
@Portal Opener You really should loosen that tinfoil hat buddy lol.
@Portal Opener Time is relative depending on location so if you sent a signal to someone FTL who had a relative time to yours two seconds slower then you, you would infact talking with them in the past breaking causality and creating a paradox therefore it is impossible.
@Portal Opener yeah, log off the internet pal, looks like you really need It. Go for a walk
Ah the ole Eschaton… lovely memories of singular skies…
Singularity Sky was a good book :)
How the hell did I not see that pun coming.
Because it was traveling toward you at a speed equal to or greater than the speed of the signal with which you perceived it.
“I guess they didn’t see it coming” 😂 that’s a real astrophysicist dad joke… I like it
Could the logical problem of FTL making the fermi paradox so much worse in a scifi setting be avoided, if the propolsion method requires some sort of infrastructure at the destination, like both ends of a womhole needing to be constructed at one place and then seperated at sublight speeds?
You could make a warp drive like this, with a path that puts negative energy behind you and positive in front.
This is mentioned in a previous video as a possible solution.
Good point. Space travel is easy in concept, but extremely hard in reality.
@John Smith You must be an alien posing as a generic human "john smith"
@John Smith cool story bro.
Turns out every idea is made up though....
Five minutes in: "Voids of existence are appearing at random all over the shop from nowhere in particular." Well then.
"Tachyons cheat reality by being a particle that exists on the other side of the light-speed barrier" OH SHIT I'M FEELING IT.
HYUH!!
*TAKYON!!!*
Would be a sad day for that first light speed pilot when he realizes he just travelled to heat death 3 seconds after spooling up his drive.
remember the movie pandora, where they thought they had traveled for so long the stars had went out, yea, fuck that lol
@@specter86fl Just remember that a photon can be created out of the blaze of the first star, bounce around for millions of years inside of that star before eventually escaping, then spend billions of years travelling through space and time to reach the earth only to eventually help some weirdo tan their asshole. and in all of that time none passed for them.
@@specter86fl What movie? Can't find it.
@@specter86fl Can you provide some more info, like Red Forest, I can't seem to find anything about it, and it sounds intriguing!
@@specter86fl Preferrably, say, an IMDB link or something, or at least a description of "the one directed by this person with this other person as the lead".
Hopefully, one day we are able to create the ability for FTL.
For now we'll just have to stick to sci-fi, and its ability to travel at the speed of plot.
but with scientists being used as political pawns nowadays...same with some doctors (looking at you fauchi) i dont see it happening nearly as fast as i would mere years ago.
@@romanplays1 your not a Covid denier are you?
@@romanplays1 I will give you the benefit of the doubt and assume you are referring to how science was delayed hamstringed and kneecapped by politics and stupidity. Or like the clusterfuck that is SLS, or with scientists being used as pawns to promote stupid shit like lead in the air is fine or climate extremification isn't real.
@@Alex_Barbosa COVID or not, if you think that scientists can't be bought as easily as politicians then you are foolish. Scientists are human and are not infalliable.
@@housetheunstoppablessed4846 a single scientist can, but believe it or not, the scientific field is not the most lucrative. People go into the field because they are passionate and want to learn and use that knowledge to improve humanity. They are not in it for the money because money simply isn't that high or consistent in the field. And scientific research and development is peer reviewed. Meaning no one person or small group of people can make decisions on what is or isn't scientific fact. It takes the entire scientific community to review and test each other for their flaws. Everything is always in question and open to being changed for better results.
Basically what I'm saying is you can't buy the entire scientific community because the majority are not in the field for money and taking bribes to lie about their research would be antithetical to their chosen path in life. It's ok to be skeptical, that's what science is, but at some point you have to trust the people who have given their lives to becoming experts in their field, because if we don't, then the entire foundation of all technical fields falls apart. We can't be experts about everything so we have to trust each others word when it comes to topics that they're more proficient in than us.
"Negative cookies" is the saddest phrase I've ever heard......
Let's just hope they aren't "toxically negative cookies"... 😅
@@saalkz.a.9715 lol
Can we loose weight on negative cookies.
@@vilaintrolltrollinsky8007 ......probably?
Just found your vids a few days ago. I've been binging them ever since! Great explanations of complex topics!
Welcome
Oh man, I'd love to be newly discovering Isaac!
This man has given me many hours of enjoyment, expanded my understanding of the universe, and improved my critical thinking skills.
@@charleswettish8701 me too
Might I suggest Parallax Nick and SEA, both are fantastic channels. Also Event Horizon and John Michael Godier.
Also astrum, cool worlds and kosmo
That opener gave me life, you’re my hero haha
Yes.
Well... I for one will keep hoping that negative mass is a thing, and some nerd will name it 'eezo' while giggling profusely.
I understood that reference.
It’s all fun and games until Charon breaks apart to reveal the biggest tuning fork in the world.
Wait, shouldn't it be "ggzo"
Ah, I see you’re a man of culture as well.
I'd call it "Spice."
Ah, cheating reality. A favorite trick in unsuspecting video games. And a further reason to contemplate reality being a video game.
it is
gg
Graphics are amazing but the story sucks.
doesn't matter, there are many amazing side quests. currently lvl'ing up magic and shadow work. these quests are quite challenging tho 😅
just remember, it's all fun and games until Valve Anti-Cheat gets implemented.
I think most would rather play through than attempt a speed-run though.
The best way to explain why math says things and reality says no is that we made math up (and I should note that this is one view of math, there are others). In this view, math is a fiction that happens to be very useful when analyzing reality, but it is just that: Fiction. PBS Idea Channel did a good video about this, but the reason math is this way is the same reason that language is this way - we made both of them up, and they're totally arbitrary. If we had a better way to analyze the nature of reality than mathematics, we would use that instead.
Of course, one of the other major views of math is that it's discovered, not invented.
At any rate, math doesn't care if the numbers you plug into an equation that models a phenomenon are physically possible, or even meaningful. You can still crunch the numbers and get a result.
I believe that math is objective. However, all currently known physical equations are approximations, and we do not know if the approximations break down under certain conditions. For example, the equations of Newtonian physics say that any arbitrarily high velocity can be achieved by a applying a sufficient amount of kinetic energy to an object.
We know that the current relativity is an approximation because it can not explain quantum effects. Or more generally, we know that all of physics in an approximation because research is still going on in that field.
0:15 - “I guess they just couldn’t see it coming.”
Eddie Murphy - “Laugh or don’t laugh. None of this groaning s**t!”
Your early episodes are superb, Isaac. They are where I started and got me hooked, not only on this channel, but on science and futurism RUclips. Don't hush the early stuff up!
Nothing can exceed the SoL
Space can expand faster than the SoL
Space is "nothing". Zero mass.
So to get to infinity and beyond, Buzz Lightyear needs to go on a diet.
Space is not nothing.
@@singularitysquaredllc.895 Indeed, and that's not what he said. The air quotes and subsequent clarification weren't there for aesthetic, the use of the word nothing, however, was. He chose it for the appeal of symmetry.
mathematically there is no way do define infinity. as its name defines it says no end defined. still its not being defined is not a proof of it doesnt have an end.
its just defines the point of end is far beyond reachable limits. but no technical or mathematical definition that it will not end. :D you need infine charge to reach to infinite. wich means you have to charge infinite time. and as you start from 1 :D ...
So then instead of designing our ships to travel at the speed of light, we need to design ships that travel at the speed of SPACE!
Brilliant, problem solved, just make an engine that runs on space
I mean, if a ship could delete the space between it and it's destination, that'd technically work.
You probably need a PhD to describe what that would look like if it passed next to you though.
"Events happening after their cause, for instance."
As events usually do.
In which Isaac goes on a rant about how negative mass doesn't necessarily exist
@Portal Opener how so?
@Portal Opener That’s a shit ton of reading, I’ll come back to this and give my thoughts in a few hours.
@Portal Opener ookay buddy I think you really spend too much time on the internet.
@Portal Opener You would be a great techno babel writer as a science fiction author, it's too bad that you waste your potential on being a moron on the internet. go write a Sci Fi book, i'm sure it would be cool if you put this much effort into it.
There was a recent study that found that by using certain geometry we can create a warp bubble with normal matter, it'll take a Jupiter's mass worth of energy so it's still not very plausible but better than negative matter.
Is this geometric algebra or something else?
I thought that they got it down to around the mass of the moon or something.
I heard something like that as well, but the problem is still accelerating the bubble you created to above the speed of light, which is still impossible.
@@gammarayneutrino8413 But exactly maybe not. Does empty space itself have mass? The bubble may not have a speed limit. The bubble might isolate what's inside to the space outside. When I write my own science fiction I look for plausibility, that's all. If you are going to exclude FTL from all stories then you're going to have a lot of limited freaking boring stories.
In a physics FB group I joined a discussion asking of space-time. can move. Someone said yes. not sure what that would mean or be like but maybe in a super-fluid sort of way the motion might be effectively friction-less. What do we really know about space-time and it's properties. Do we even know if it is Euclidean, spherical, hyperbolic, or something else we haven't figured out yet.
the opening pun violently murdered me and then brought me back to life to do it again
You are very informative and always have excellent visuals. I honestly don't know how you aren't more in the spotlight. More people need to watch you and soak up these information packed videos.
Thanks for all the journeys you have taken me on so far Mr. Arthur!
I'd like to mention, the Chronology Protection Conjecture isn't the only response to time travel paradoxes that could be caused by FTL. There are other conjectures as well which I believe stand on the same footing.
- Cosmic Censorship: If something reaches into the past it cannot affect it due to being behind an event horizon. No interaction no problem.
- Consistency Principle: Same as before but if something goes into the past it cannot alter the course of the events in a way that would prevent the cause from generating the effect even in the case of inverted causality.
- Parallel Universe: Similar to the one above but essentially when there is something travelling back in time the universe essentially splits at the quantum level, relegating the altered timeline to another universe, essentially turning the closed timelike curve into a spiral
And finally, I'd add that Miguel Alcubierre expressed concern about the CPC however he also mentioned that it wouldn't disallow FTL perse but rather that it would make it impossible to use FTL to make a time machine.
What do you think?
The Universe really dislikes you changing the past.
Pockets of space emerging randomly are why I'm fat.
XD fukin ded
22:11 Basically a real-world Nether portal. Space in the Nether is 8 times more compressed than in the Overworld.
That was my thought as well, although i haven’t played much Minecraft, but I’ve heard that comparison used in another video on this topic.
Isaac, your early shows are really great. I've been a big fan since you started doing regular episodes and frequently go back to watch some of the earlier videos. I'd hate to see them go or be replaced:(
sure the production value is better now, but many of us wouldn't be here if it weren't for those early videos.
after all the primary ingredient here is hearing the concepts discussed, elaborated, and expanded upon rather than the eye candy...but the eye candy helps. drink in 1 hand, snack in other:)
keep up the great work!
We have a speed of light because the graphics won't load fast enough if you're moving faster than that.
SO what you are saying is that we don't have aliens because the simulator of our univers has a shitty GPU? what an asshole, buy a 6900^8 XT at least.
Most fiction that doesn't contain timetravel is also full of plotholes. Many authors write plot holes.
Plot armor is a thing for the main protagonist.
Fair point, and the usual top 3 scifi novels on polls, Fouindation, Dune, and Ender's Game are all critically dependent on 3 massive plotholes but are still great [Psychohistory, water shortages for interstellar empires, children as strategic geniuses for anyone wondering]
The only space cowboys I've seen who don't leave stray plotholes wandering everywhere are those who stay corralled within one star system.
If a country created a film studio complex with an excess of plots, then you could run a cable to Hollywood where there are major plot holes and create a giant battery. Such a literary potential difference could power the world!
Well, you go ahead and write a popular SF series where it takes most of a characters life to get to just one place. Each main character of the book/movie may have to be a descendant of the previous and do new world building every time. See how well that goes.
The laser point moving across the surface of Mars "faster than light" is a concept that I'm sure, if I could fully wrap my mind around, would really help me understand this subject.
I kind of get it, I think. The point may go from one side of Mars to the other faster than light, but from the perspective of the point, no info goes directly from one local to the other, all info moves through the source of the laser and back to Mars, at the speed of causality.
Am I thinking about this correctly?
The photons have a speed, being fast enough to take minutes to get to mars. You can flick the laser to point at different areas of mars very quickly, changing your angle really quickly. Then that gets multiplied over a large distance until your "point" is traveling "ftl" in terms of distance between when it was still and when you moved it.
But the effects still only happen at light speed, the laser flies to mars at that speed.
One can almost imagine the laser like a water hose, you can flick a water hose to point to a new spot quickly, but the water still takes the normal time to get to the targeted location.
@@Ottriman That analogy of the water hose is perfect!
@@Ottriman Thankyou!
The hose analogy really worked for me!
I have a way of "visualizing" it now. (pun intended) ;)
@John Smith dude why bother repeating that 300 times we get it you are very contrarian congrats
That ship 2 minutes in vaguely reminds me of the BC-304.
*Happy Stargate Noises*
Kree! :D
Cue Carter's elevator humming
I am guessing that's its inspiration, weirdly I always thought the Daedelus was a shout out to the Trek Federation's side nacelle setup
The first 10 minutes of this video is pure gold. The best explanation I’ve ever heard.
So... A whacky idea here.
1. FTL is not possible because it would break causality.
2. galaxies are moving away from us faster than light and do not interact with us. There is no causality between us and them.
3. How about an FTL drive that goes from here to one of those galaxies that are no longer in a causality loop with us? A drive that works on ridiculous distances but not up close.
Doesn't sound like it should break anything.
could be a fun engine idea, one caveat would be that any point in our region would only be able to access a single point in their region.
19:01 I don't know why the Santa imagery was so funny to me.
Oh that intro pun. 😅 Yet another great informative video to watch during lunch.
Isaac: Here's what a universe with FTL would look like
Also Isaac: Spends the entire episode explaining why FTL isn't possible, instead
i feel like i just fell for a trap. i came to this video because i wanted to know more about FTL and how to achieve it one day, but i've left not only convinced that we won't, but that it's good that we can't.
Isaac, you cheeky sausage, you.
2:50 I always like calling the speed of light the speed of causality that's why it's abbreviated as c
I always thought it was 'c' because of it being 'constant'
I'm sure most of us are familiar with the idea that space/time, but this video and the way you reframed the concept so thoroughly and articulately, might very well be the first time the concept really made it 'click' and make sense to me, beyond just being able to repeat the law.
Very well done!
love and respect from india!
I think the hardest clue that “Light Speed” is an unbreakable upper limit is E=MC2.
WHY should the energy of mass be a multiple of C??? But somehow it is .. woven right into the fabric.
Not only absence of FTL prevents Earth colonization, but inability to break FTL is actually the main reason why this Universe exists. When only causal Universes can meaningfully exist, it automatically implies at least rudimentary logic for this Universe. That's why logic is the king.
But the presumptive impossibility of FTL will NOT prevent colonization. It will just make it a slower process, in which there is no real-time communication between the frontiers and the original star system. Conceivably, Tellurian (earth-origin) life could spread through a wide region of space, even beyond the Galaxy, without FTL.
@@oldionus Yeah, but it prevents colonization from not only other galaxies, but also from beyond observable Universe. It reduces chance to possibly surrounding star systems, Milky Way or if we stretch it from Andromeda, but prevents basically the rest of the Universe. That's a big reduction.
This episode has been terribly thought provoking. I never knew that a photon does not experience time. A wonderful lecture, thank you.
another thought though this is the sci-fi writer in me spinning something out. speed of causality gave me an interesting idea for a potential limit on minimal distance that can be traveled by FTL, it could be that you can actually arrive before you leave in objective time but you cannot be perceived arriving by an observer at your starting point. the light from your arrival at a distant star has to arrive at the your starting point sometime after you left to maintain causality or be so far away that the starting point cannot observe the end point do to universal expansion. of course that would make it imposable to go a light year away by FTL but easer to go to the edge of the universe where things have already moved beyond where the light can reach us.
Getting to your destination faster than light would mean the light indicating your arrival would by definition arrive after you left, whether you travel 1m or 1lyr. Its you who are traveling faster than light not the light itself.
There's been some suggestion on atomic rockets that quantum effects could destructively interfere with time travel. or at least paradox's. So a drive might work as long as no paradox's where created, and might self destruct if used in a way that would cause one.
@@voteindependentforindepend7181 I was referring to the speed of causality and traveling faster than it would by definition be time travel. Meaning that you arrive before you leave in objective time. Which would violate causality.
To preserve causality and prevent paradox, traveling beyond the point where you can be observed could be a solution. If you go ten lightyears as a speed that results in you arriving 20 years before you leave then the light from your arrival would show up ten years before you leave.
This is the causal relationship I'm suggesting needs to be avoided. So if you can only go at that speed you have to go to a point beyond 20 light years to maintain perceived causality.
@@spacepiratecaptainrush1237 but you dont arrive before you leave. Even if you're traveling at trillions of times the speed of light(causality, Isaac makes the distinction but they are effectively the same) your trip will just be extremely brief, depending on the distance travelled.
Traveling faster than causality is time travel. As you near it time slows, surpassing it time starts moving backwards.
Really love the idea of the “speed of causality”. It’s so much easier to apprehend that idea when talking about limits.
For non time travel related causality issues I am probably wrong because quantum physics is the realm of masochists but if i am on the earth and there is another guy on the moon one light second away and we are sending signals back and forth to for example argue about the laws of reality on youtube comment threads and I use some FTL method to send a signal to the moon in 0.1 seconds 10X faster than a standard speed of light transmission how does that violate causality?
I write up my message, then I hit send, then an amount of time passes for both me and the recipient, and then the signal arrives. For it to violate causality wouldn't the recipient have to receive the message before I sent it? that would require it going there in negative time which would be faster than infinite velocity right? like if I have ftl that sends signals to a place one light year away I can send a radio signal and get a reply roughly two years later. if I have FTL radio signals that go 365X the speed of light and I send a signal one light year away on sunday the recipient should get it on monday and ill get a response on tuesday, how would that violate causality? Sure it would be faster than light but why is light necessarily going at the maximum speed of causality?
for warp drives where you send a chunk of spacetime to some place else in less time than light would take that still takes time and still shouldn't violate causality. now, if you could send a signal to someone on sunday and they received it on saturday that would violate causality but the other ways I don't see how they violate causality.
I personally find it way WAY *W A Y* harder to understand because rather than just "fast thingy gets heavier as you speed it up so it becomes slower thingy requiring more energy to make it a faster thingy each time" it instead relies on relativistic time and local time and time dilation and all that special relativity masochism stuff.
@@atashgallagher5139 I get what you mean, but that’s not how the video explains it. In the video, and if I’m understanding right, it says more or less that lightspeed it the maximum rate at which information can be exchanged.
So of course, FTL wouldn’t go against causality as long as the result doesn’t occur before the cause. But once again, that’s not how the video uses the term causality here.
“Speed of causality” is thus the maximum speed at which causality CAN occur. In that sense, FTL has some vague meaning but “faster than causality” absolutely doesn’ so it’s easier to see it as a limit.
11:22 Does what we call "spun" take energy that would have been used to go faster? Therefore the SoL is slightly slower than the maximum possible if there was no spin?
Their is other life out their we are just casually disconnected
9:15 You made a mistake. Potential energy slows time, therefore time slows *near* black holes. The potential energy increases as you move *farther away* from the source of gravity. Thus, the potential energy's time dilation works in the opposite sign from what you said.
Time slows near a black hole because of the curvature of spacetime.
It's the curvature of spacetime that slows time, not the potential energy. The potential energy is a result of the curvature as well, not the cause of it.
WhstIfAltHist is my second favorite to this one. Should be a great episode!
To be perfectly honest if we can figure out FTL travel it will be
1. Wormholes and/or Warp Drives using gravity or mass manipulation
2. Higher Dimensional Shortcuts like Hyperspace, Slipspace, Subspace, etc
Also Mars is not several light years away but a few light minutes away
Alpha Centauri is about 4 light years away
@John Smith based on current information and theories
The explanation of entanglement using the two letters was excellent. It made me understand that concept so much better. Thanks
Lovely pun at the intro lol
I used to love reading sci-if, and this channel has brought back that charming feeling.
If you only have imaginary velocity then you can only move imaginary distances, which isn't very helpful if you're trying to move a real distance.
imaginary numbers ended up being useful.
banger of an episode, one of my favorites out of the whole catalog
Happy Arthursday.
It`s such a shame that other educators and speakers don`t posses your skill of explaining difficult, non-intuitive concepts. You have made it easy for anyone to start to understand the concept of relativity. Very high respect from United Kingdom. Chris.
Intelligent and/or Alien Life may very well be common... And advanced Technological Alien Lifeform developing is probably a far rarer event in our Universe and I think most people do not understand the difference! We maybe the only Species to have developed Technology. Besides always remember the old Sci-Fi Movie quote, "To Serve Man, it's... it's a cookbook!"!
Rare Earth - Rare Life - Rare Intelligence - Rare agriculture - Rare industrialization - Rare (?)
Lots of filters and we might not be done yet.
for all we know dolphins are smarter than us. but dolphins don't have opposable thumbs and they live under water so they can't develop tools and that makes us the only industrialized civilized species on earth. how do you melt metal to develop smithing to develop guns underwater? you can't, which is why dolphins haven't done shit and humans have a massive society.
Thanks for uploading, Isaac.
Don't think I didn't notice that modified BC-304 Daedalus :P
Lol it was ugly compared to its inspiration.
21:20 Yes, I love how people say the warp ideas won't ever work because they still don't allow FTL speeds due to massive radiation doses, atomic impacts, or whatever, but even a barely-functional "warp drive" operating at a small percentage of lightspeed would open up the entire solar system to us, reducing the travel time to even the most distant planets and objects to days instead of years.
well we already have drives that can do that. light/beam sails & nuclear drives are the only ones i can think of off the top of my head & they allow speeds of multiple percents of c with the light sail being able to get arbitrarily close
@@virutech32 True... eventually. A light sail could eventually reach some % of c given years or decades of acceleration. Some versions of a nuclear drive could eventually reach that after expending a lot of fuel (nuclear drives are basically steamships, that steam still comes from fuel). An on-off warp drive does the same thing, only instantly. You don't even need to be going very fast at all when you hit the switch. And it solves the deceleration problem that light sails can't and other drives have with a deceleration time (and fuel) equal to their acceleration. Just sit in orbit until you're pointed roughly at Pluto, hit the switch, squish space in front of you so you make 0.01c and reach Pluto in 28 days. Flip the switch, and spend whatever fuel you need to achieve orbit. Granted its an oversimplification, but achieving that 1%c drive would make even our current rockets into interplanetary vehicles.
Theory: actually light speed limit is just enforced in certain areas of the galaxy where aliens has put in the speed limit to help protect primitive civilizations, outside of the Sol sphere of control (around 37 000 AU radius) relativity doesn't apply and linear acceleration is possible on objects up to any speed.
Dude ... thats NOT a theory ..... lol. en.wikipedia.org/wiki/Scientific_theory
not a theory, a hypothesis
@@virutech32
yup
I too enjoyed Fire Upon the Deep
My own Sci-Fi universe has no FTL travel or communication, as a result of this channel.
12:42 I've never liked mixing large numbers with smaller directors. Like negatives and exponents.
You need your own spot on discovery channel. You would instantly be the most educational thing there! Love it thank you
Nebula which is affiliated with curiosity stream which was founded by some of the original founders of discovery channel, so yeah, he basically does have a spot on discovery channel but without the overbearing corporate influence or the corporate budget.
So traveling through the Nether could be a form of FTL... like with a super duper Elytra??
That's the general idea of phase space yeah, but more like if there were more layers, and each one was like that to the one above.
@@ben4R I guess you'd only need to do better than 1/7th the speed of light in the Nether... That's one hell of a firework!
@SoraNezumi 1/8th, but yeah.
But going a second layer deeper, it'd be 1/64th you'd need to beat.
Six layers in, you'd only need to beat 4118 kph (2559 mph) which is slower than our current jet speed world record, let alone spacecraft. If you had ten layers of phase space that worked on the same ratio as the nether, then you'd be ftl on the surface if you were walking at 1.006 kph (0.625 mph)
I think the universe is two counter rotating hyperdimensional black holes and the one we are in has an escape velocity of the speed of causality.
Also the expansion is the pull of each black hole. The great attractor is the other black hole.
At the end of time the black holes merge creating a huge burst of energy creating a new universe on the edge of it's event horizon.
But really this already happened and it's just our limited perspective from being a part of it that gives us the illusion of time and space. Like how from a humans natural perspective the world is flat and stationary.
First Rule Of Warfare: Keep Your Eye On The Enemy
Awesome stuff isaac, a very inteligent accessment! this time you have kept close to what is physically possible...
Hyperspace is the nether.
If you travel 1 block in hyperspace, you move 8 blocks in the overworld.
Would aliens even go upon the same technological route as us? I believe timing of ideas is very important when it comes to discovery. Would they even have someone who create math or measurement of distances using time? We use time as an measurement factor of reality but what if aliens biology allowed them to see a different perception upon to base their technology on that's probably more advanced then relativity descriptions. This allow factious energies to exist like Sprit Qi or Sources of energy from a folded universe/dimension or particle unseen due to lack measurement technology. It would logically make sense for strong aliens to create technologies based on FTI (Faster than information) we don't know of. Reality itself could simply be a specific type of perception of the change in a geometric dimension. Like Reality could be just a slice on a 10-dimensional cube and going FTI breaks you out that slice into a more variety of possibilities/ movement of energies that's more diverse than we know.
YOOO WHATIFALTHIST AND ISAAC ARTHUR MY TWO FAVOURITE RUclipsRS COLLABORATE
a Blessing from the Sacred Baguette
Whatifalthist is wildly overrated
@@vincentcleaver1925 Kinda true, But I mostly enjoy his videos more than I agree with them, I do agree with a lot of his stuff, but I also disagree with other things He says, Plus I never said He is one of the Best Historians on RUclips.
Love the way you're thinking here. I subbed at about 25k subscribers way back in the day. A revisit of this would be awesome. :D
You make FTL seem so naturally linked to quantum phenomena and relativity and this video is the first time I've actually understood the requirement of negative mass a requirement for the Alcubierre drive. Positive energy to contract space in front of a ship, negative energy to expand the space behind the ship.
Mind blown again, thanks for this.
I was going to invent an FTL drive...but things are just so crazy at work right now.
"things are SLOW at work" :-)
@@TheRainHarvester yes we are working so fast that time is slowing down. It's a nightmare, really.
Outdated: there have been made a warp drive mathematical model that doesn't need negative energy.
Regarding Quantum Entanglement - hasn't the "hidden variables" hypothesis have been proven to be wrong?
What do you think about the warp drive design that doesn't require negative energy or mass?
Imaginary is a bad name for those numbers, they're just as real as "real" numbers, the best way to think of them is not as a single number but a pair of numbers that are just the reverse of each other, so rather than `i5 * 5 = -25` it should be `i5 * i5 = -25` which in programming is equivalent to `r = i[0] * i[1]` or `r = i[r < 0] * i[r < 0]` so always think of imaginary numbers as square root pairs, this also implies an infinite number of number axis, not just "real" & "imaginary" but rather "n", "n[2]", "n[3]", etc, etc.
This is why a Dyson swarm of a billion artificial worlds is our only real hope for a sci-fi future.
Think "Firefly" and wear a brown coat. All those little moons and dwarf planets are terraformed worlds. But please, no lunatic undead ...
Honestly I think that in the future people will play full dive true to life quality VR games that are written, produced, and voiced in real time by AI as you play, you can then live in a simulation of a world or game as the story plays out around you with everything impacted by what you do.
The flexibility of D&D ran by a human but the quality of a AAA videogame title and the immersion of direct nerve interface VR with the capacity to make decisions that you normally only have in a story when you yourself are the author. In fact you might get people playing games where they have their memories altered or blocked temporarily so that they think that everything is real or that they are someone as a character in the story.
If you have some matrioshka brain AI god machine it would be no problem for it to manage writing a story, producing the world, simulating all of it, and basically being an actor for every single NPC in the game giving them all sapience in there quality of interaction but without creating people because it is just an AI controlling them not new synthetic people made just for your game.
Then you can finally fulfill your dreams, or get a well written ending to mass effect 3 or an actually well made mass effect andromeda. I bet people will spend decades in single worlds / stories before moving on sometimes, and it will be way better than sitting around doing nothing on your couch in a giant mansion as an AI does every single job better than you ever could. And reality would get boring after the first few thousand years if everyone is trapped in the solar system and maybe the few nearest neighbors.
But it is proven mathematically that the Alcubierre warp drive is possible without negative mass only using positive mass which makes it much more likely to be possible and as they work on it the energy needed goes down, so it could very well be that warp drives and FTL are possible just really hard.
@@atashgallagher5139 vr on the scale you've described would make reality obsolete. Who would even care about ftl at that point?
Imaginary speed is when I think about going for a run, but don't.
I got no clever joke for this one. No Doctor Who, No Hitchhiker’s, No Blake 7. ANYONE EXCITED ABOUT The Foundation TV? 😂😂😂
When does foundation begin?
@@TheRainHarvester supposedly September
Maybe we should start hitting Charron with some really heavy shit until we get it broken apart.
Wow these are all basic concepts that I've know for well over a decade, but I feel like I know how they all actually work so much better now, your explanations were incredible.
Team *Alcubierre drive* Go!
I'm in the *Wormhole Team* but GO WARP DRIVE!!
I am still rooting for mass effect drives which are in a way a modified warp drive so I say someone should go nuke Charon a few times. but the Alcubierre warp drive is possible without negative mass using only positive mass, now how you would actually manage to do it is another question entirely, but theoretically it is possible to make an FTL warp drive using only positive mass.
So what you're really saying is that we should go send some mining equipment to Charon right away to do some exploratory digging and scanning for large metallic structures in the middle that are currently dormant but can be reactivated? That seems to be what is being suggested here.
When you break entanglement, you are still sending information. The "contents" or value are not as important as the fact that it has been broken. Think of "one if by land, two if by sea". The difference between 1 or 2 pairs being broken is information transmission.
but being unable to force a specific outcome removes any "value" from being transmitted.
@@TiredRoman The point is that the value is irrelevant. All that you need to know is whether the entanglement is broken. Take the letter analogy. You have some number of "entangled" letters on your desk. If you see one letter being "opened" on your end then you know that it was opened on the other. If you see two letters being opened, then again you know they opened two on the other end. The content of the letters is meaningless. You just have a pre-arranged agreement that opening one letter means one thing, and opening two letters means another. It is the number of broken pairs that conveys information.
@@ravenlord4 There is no way to know if the other letters are opened though
@@TiredRoman Sure there is. The whole point of the entangled particles is that both are in a superpositioned state. As soon as you see that the particle on your side is no longer in a superpositioned state (ie it has some value, and it does not matter what that value is). then you know that the entanglement has been broken on the other side.
@@ravenlord4 if you "see" the particle then you have already broken the entanglement. You won't able to tell the difference between you inciting it breaking vs your partner doing it.
Of all the shows i've watched which has time travel only Steins Gate is the one with no paradox. They shift the world-line every time a event happens.
I think these discussions fall short logically, rather than mathematically. I'm no physicist, however I fail every time to understand how time and space are the same thing, and causality is tied to this concept. So I too separate causality from the idea of a speed limit.
Say for instance that I live here, on Earth, and Betelgeuse has JUST exploded into a supernova. The speed of light dictates that I'll see that light only once it has reached me. But does that mean that the event hasn't occured? No, it just means that light has a distance to travel towards me. The conflation between time and space is not present here. Likewise, if I travel towards Betelgeuse, even at a lower speed than the speed of light I'll reach that light sooner than if I stayed on Earth. The causality is not violated here. Likewise traversing space over the speed limit does not in any way create a paradox, because the event HAS happened, the LIGHT merely hasn't reached me.
It's like arguing that a supersonic jet emits no sound because you can't hear it yet. I just can't wrap my head around it and keep thinking it's solipsism on the part of the scientists. Maybe clearing THAT up will help people understand the underlying problems with FTL, or make the scientists realize they are perhaps talking about another SPACE dimension, not a time one.
Lastly I'd like to point out that it is theoretically possible to eliminate the event horizon of a black hole with spin, without breaking lightspeed, which would also break causality (the naked singularity problem), so I guess we have no choice other than kugelblitzing a Black Hole into existance and immediately spinning it to open this pandora's box once and for all. Who knows? Maybe that's the Fermi Paradox explanation right there. Fusion Power > Overpowered Lasers > KugelBlitz > Unlocking the secrets of the cosmos > Death?
@John Smith you have to be the least open minded person that follows this channel, why are you even here?
@John Smith Energy requirements does increase exponentially the closer you reach c however. Though I still think that is the work of another dimension causing this effect, rather than time itself.
Don't have any proof, but it is an avenue I'd research, were I a physicist.
Learning that the speed of light and speed of gravity waves are the same speed of causality and neutrinos just a tad slower still was awe inspiring, and it those were fairly recent discoveries. Go science.
@John Smith Just stating that does not make it true. There was a experiment that confirmed that withing experimental sensitivity both the gravity wave and photon wave arrived at the same time at earth from some explosion far away. Im happy to change my thinking if other better data comes up, until that time Im going with the boring mainstream view.
Do I want the speeds to be different ? Yes.
Stuff like this makes me wonder, why do we still measure speed in arbitrary units, like m/s or km/h? (not even mentioning other units. Looking at you, USA)
We could measure speed in nc (Nano c) or pc (Piko c). That might remember humanity how irrelevant they are. And it could also shift the way we think from zero speed as absolute towards max speed as absolute.
In so called "natural units" the speed of light is exactly 1 planck distance per planck time.
Because these units to the common man are just as arbitrary as inches/second or cm/hour. You would arrive at a °K vs °C/°F situation again.
around 21:20 i had some crazy nostalgia from when the professor (futurama) explains that his ship doesn't move in space but it moves the universe around it
2: 50 I prefer: Speed of causality.
Your explanation of the speed of causality in layman's terms was both fascinating and, as a aspiring scifi writer, really helpful. Thank you.
Poor Science Fiction writers/ hacks do this all the time.... STD did it with “Sonar” in space for example.
Not having FTL makes stories involving interstellar states and entities boring... If would be impossible to communicate in any 'meaningful' time with others 500 light years away for example.
@@musafawundu6718 Holly hell, the aliens from alpha centauri have fired a missile into the UN headquarters, we must fire a return attack. Humans build a giant missile and launch it at alpha centauri. Ok boys, time to wait ten to twenty years to see if we won the war or if we need to send another return shot.
or we get contacted by aliens in alpha centauri asking for us to communicate we send a response, and then then next eight years there is no response as we wait for them to gt ours and send one back.
see, that could be interesting if your book took place over thousands or millions of generations.
That cleared things up to be sure. Good material.