The Quantum Mechanics of Time Travel

[@aky19832001]

Great video. I hated physics in my college days. Years latter, I've gone through my old physics with calculus textbook twice!! Took me a few years but I now find my self appreciating everything and understanding laws of the universe far more clearly.

[@aj-tg]

This guy laughs at 9:59 phase shifted and interfered with itself.

[@TheAlienilluminati]

His laugh though! lol

[@jamesanagnos6123]

lol

[@jonassenify]

sounds like donkey yawning LOL

[@jstriker623]

He's a tool-

[@keananjacobs9133]

Thought he was choking

[@strandloev]

10:00

[@TGC40401]

Delayed choice shows that the universe does time-travel constantly, and gives you a template of how you are required to accomplish the same task. The universe is never wrong, it's that simple. Where the information goes, when it doesn't arrive to destroy itself, and whether it splays evenly throughout the universe, and what effect happens to the universe, in such cases, is still on my mind. I once had a weird dream, with hockey and quantum mechanics. I had to step away from my computer when the hockey stick came out, as this is exactly how I would have told myself that my future time-travel was/will be successful.

[@ThinkTank255]

I am a Ph.D. computer science student, but I studied physics as an undergrad. Physics has always been my passion, since literally as far back as I can remember (2-3 years old). I invented the flywheel at age 4. Spark-gap radio transmitter at age 5. I have a very deep knowledge of physics and mathematics now. I don't think I was pedantic. I find it very hard to believe, given your comment, that you understand this stuff. You've got a LOT more learning to do.

[@andykod77]

So 11 years later have you made any more progress on your physics/inventions career?

[@petermoon4556]

The best part of this lecture is precisely at 1:07:51 when you hear him giving this rather bizarre laughter, which he did one before in this lecture only once (but for a comparatively short time). It is a distinct laugh. I can see people have made negative comments with regard to his theoretical as opposed to hands-on approach. Perhaps you can find some context and joy in his laughter. I do realize, however, some might find it unsettling. I was amused and wish I could can it. It would make a great laughing loop.

[@jessepanganiban2529]

Tough crowd.

[@thechuggs8997]

Just like my graduate class

[@amberswain6826]

Lol

[@vinniscarboni4095]

I concur human👽

[@sm0ki649]

Wanna know them spaces

[@andykod77]

Aren't they all?

[@Alex_1729]

His laughter is so nerdy. I liked this lecture, very informative and intuitive

[@Gromwald4178]

I studied various subjects related to time travel including a masterclass on philosophy of time. I am planning on writing a course on time travel.

[@andykod77]

Did u ever get round to that?

[@marinarepan5578]

Great that I found this video. I translated Seth Lloyd's book Programming the Universe from English into Ukrainian. Now it's a pleasure to listen to things Seth Lloyd says. If only they gave me more of his books and others' ones to translate. The book is just terrific.

[@nosuchthing8]

Apparently CTC (closed time like curves) are possible, as is actual time travel. The problem is that the energy required is prohibitive now. Godel found solutions that lead to time travel almost as soon as Einstein unveiled his theory.

[@S3DGamerZone]

I love the relation between thermal dynamics and the quantum mechanics of time travel, very cool.

[@KeyOfAm]

19:30 The electron/positron thing blew my mind

[@alexanderlyberth9821]

Time travel is an perfect example of a normal human being wishing to travel back in time because of of a normal human always regrets or wishes someone beloved one to come back :)

[@schmetterling4477]

I lost someone a little while ago. I don't wish them to be back. It wouldn't make anything better in this world, including to the deceased. Humans are evolved to move on.

[@demondik]

Couldn't simply stopping someone on the street to ask them for directions throw their time line completely out of whack?

[@KultrunAus]

every time we interact with someone we irrecoverably change their life for better or worse

[@Leto85]

If you read this, my apologies for interupting the vanilla course of your life but simultaneously I want to welcome you in tne new version of the course of your life.

[@skepticalbadger]

Yes, but only under a multiverse model of time travel. In which case you're changing their future but not yours.

[@claudiosalib774]

Mr Lowery Sir, so too could by engaging in some form of onanistic display of pervasive behaviour for which no justifiable excuse may be given to excuse one's self righteousness, which lead to the perturbation to begin with. 🙄

[@AniRhythm]

that's actually what I was thinking about when I made this post - and the data didn't travel faster than the speed of time. - this also means it can travel to another time zone instantly - thus traveling time in a practical non fiction way. - ie I'm not 12 hours older traveling from the US to Europe. The only way imo to amplify that effect is with greater distance

[@jenjourneys]

interesting subject here. I am new to this topic so alot of this is over my head but I will come back and watch again. Thanks!

[@danielleal6202]

10:00 rlly loved that part

[@tilakdey0]

Sir, Where exactly should the singlet lie on the curve ? 35:00 onwards.

[@claudiosalib774]

Perhaps near the spindle of a washing machine to which a generous amount of bleach may be poured wherein thy singlet may be baptised and worn another day without the stain of it's last wearing. Suffice it to state that thy singlet will be whiter than it has ever been. 🙄

[@vibration1028]

Sir , we are able to watch this beautiful lectures which recorded in past , but somehow ( yotube ) we are able to watch in future without harming anyone .

[@juanmedrano2616]

Great stories to start! Love it!

[@CraigCline]

The history of ideas is important as it portends where the 'next' idea comes from. Good idea.

[@williambrownjim]

If you time travel through a machine isn't it possible to go to another universe you created at whichever time you wish.

[@jackpullen3820]

At 32:28 Could it be that the memories are stored in the field loop not erased. That could also be the marker to exacting point of return from other dimension. The only way in is the only way out.When you return, you remember everything to the point up to leaving and memories of the trip are in the loop field...

[@linuxaddict11111]

i like the idea that there's only one particle. zooming around at infinite speed, appearing thus to be everywhere at once - hence, entanglement.

[@imacellphone]

I may or may not be about to waste an hour, but I'm gonna give this guy a chance because I fucking love learning about quantum mechanics!!

[@justaronee]

one book that's a combination of not changing the past due to "a quantum fluctuation" and also being able to is the book 11/22/63, a man goes back in time to stop kennedy's death and he realizes that the past actively resists being changed. Like for instance, he bough a brand new car 2 days ago, he needs to go across town to stop something big from happening and then the car breaks...

[@venus_tv3801]

The Quantum Mechanics of Time Travel

[@mjojo56]

Anyone else notice the subliminals (sm)? This was a great lecture hard not to learn something. I look forwards to more. Donidorko (movie) is a greak example of the coffee cups handle as he is in a time loop after death and returned to that resting or natural state as he returns to the original time line. Something similar may be the case with black holes but can't be indefinitely proven.

[@CalvinHikes]

Don't be disrespectful of Hot Tub Time Machine! 7:40

[@waffle98501]

The book "Starfire" demonstrates many time travel methods, including a "time trap".

[@walterchavez3081]

Another paradox (maybe not the correct word to use) could be that things going into the past will add extra matter and probably energy to ( at least to the past's ) universe. This probably breaks matter creation laws and would be a possibility of filling the universe with matter. I believe the 'Unproven Theorem Paradox' described at around 13 minutes into the video is also often referred to as a 'Bootstrap Paradox'.

[@Leto85]

I've been wondering about this for quite a while now and I like to do a thought experiment on this; Let's say we have a universe and in that universe where all matter is present and eventhough ever changing forms (creation and decay) in all points of time there will be the same amount of matter because at all time the same amount of matter is present. If some particalfor whatever reasons decide or accidentially not just on purpose removes itself from one point of time to either appear or re-appear in another point in time and stays at its destination there for 5 minutes while being away for 5 minutes from where it had left, then that means that the universe at the time of his departure is for 5 minutes long one partical lighter while at the point of time of his appearance or re-appearance the universe is for 5 minutes one particual heavier. Can this universe withstain itself when it's losing or gaining weight?

[@jesushlchrist4574]

Good question???

[@tigeruby]

this is truly exciting & brilliant stuff

[@ethosflux]

Actually the P = NP computational paradox proposed by Moravec is probably the strongest argument against the Novikov self-consistency principle.

[@giovanniwitesbolzanassumpc1647]

Screw that's 44:50 glitch. Anyone got the fixed video? Or it was a some naked electron that hit the camera man...

[@AnonningAnon]

" You're right, I was unfairly scoffing at you" lmao priceless

[@WingMan1]

For those interested I had a time travel experience when I was a kid which I am 95% sure was an OOB experience though (which I used to have many of) and not a physical one. I do actually have my doubts regarding physical time travel. Anyway for the open minded here that might trust in my experience the one thing I noticed of importance is the loop. So the scenario was that aged 8 i enter a wormhole that for some unknown reason appears in my bedroom, and travel 15 years in time play on a game boy in a dept store (hadn't been invented yet) go back to being a kid. 15 years later I re-lived that same day as a adult. So here is my hypothesis. To time travel that took place and the information i was exposed to was bi directional. So I took a peek into the future when I was a kid and no doubt could have changed the future by for example persuading the Gameboy maker to call the toy a Gamegadget! In which case 15 years forward would mean i would end on playing on a Gamegadget and not a Gameboy. What blows my mind is how free will is sill possibly in a closed time-like curve!?

[@Toshio_77]

Wing Man, I know this is 2 years late but, if we consider that the wormhole was not real (I just can’t explain it with this theory of mine) then perhaps u experienced déjà vu, and your brain accidentally placed the 33 year old you’s memory in the wrong place in your brain, such as in the 8 year old memory file in your brain, your present you will look back to when you were 8 and think that you experienced the 33 year old memory twice over, once when you were 8 and the second time fabricated to fit logic which is what 33 year old you would assume should be more recently

[@KingHOV]

This is the most interesting lecture ever

[@deanjenkins3077]

What if by traveling in past we just leave our initial timeline just without us and create a new timeline where weverything is the same but with us from future in it? This way one can actually meet "oneselves" and it would be a meeting of two different people, since they have same origin but different outcome. Grandfather paradox is solved because traveler is "cut" and pasted into an old timeline, changing it into a new one, and if one's old self is present, new one can kill the old one and still be alive, because new's self isn't in this timeline, thus travelers can't change their past i.e. their origin, but can create a new timeline based on past, but with traveller in it.

[@breadrichardson]

Really enjoyed this! Keep them cominggg! 😁😁

[@BlvdRo91]

I find it extremely interesting that I can enjoy this content as much as a world star knockout and my two favorite artists right now are Kevin Gates and Chris Stapleton. We humans are diverse and complex.

[@timloc6608]

You can’t be dead and alive at the same time one+0 equals one0+1 equals one

[@PeterGibbonns]

Wow your so unique.

[@eszterle]

10:00 Best laugh ever ...

[@arthurnguyen-cao1577]

I am convinced that Christopher Nolan saw this lecture and decided to make two movies about it.

[@KINGDROWSKY]

it picks up after 13:22

[@Gromwald4178]

I have studied this stuff for some years now. He makes sense to me.

[@PeterGibbonns]

Oh lord.

[@johnsmith9246]

I wish I had the intellectual capability to better understand this topic or others like it. Nevertheless, to the degree that I could understand it, very informative, a great lecturer.

[@dondrake100]

i have not yet traveled "back in time", but the future i have visited via dream state in my childhood , i dreamed of things that have come true in my own life line.

[@captainhampton]

Great lecture! Seth Lloyd is awesome.

[@ihaveatonofnames]

You said it!

[@pyrrho314]

"Primer" best time travel movie ever for science geeks.

[@Gromwald4178]

Some argue that the experiment is not an example of time travel. Godel however proved that closed time loops are possible. Wheeler's theories included retro causality. This is not time travel but does involve influencing the past.

[@richardpayne1458]

Are hair follicles small enough to be influenced by quantum mechanics? therefor causing the hair of a person to be in two states of existing and not existing at the same time?

[@80thiconoclast]

Awesome class. Was 46:49 an example of time travel?

[@tamcuatoi]

The Paili Exclusion Principle states that each electron has a precise coordinate designation and that no two electrons can occupy the same coordinates at the same time. Going back in time would violate this -- would it not?

[@rezayo3145]

19:44 that laugh tho

[@nishchaljain9264]

Jump to 9:57😂😂😂😂

[@arminhempel]

you obviously never made it to 1:07:51

[@starchild2121]

@@arminhempel exactly what I was thinking lolololol

[@Dammynath]

I enjoyed this lecture.

[@keananjacobs9133]

Who's here after hulks explanation about back to the future.

[@tilakdey0]

You can say I am here after hulk explanation! Actually I watched dr strange after avengers endgame, curious about time dimensions

[@Digifier]

Omg, it's Wornstrom from Futurama :O.

[@JohnFHendry]

A black hole is initially created by the second harmonic comma. And yes, the arrow of time moves up, not forward. But there are two arrows and time moves backwards to move forward again because E=T and time must also be conserved. Mass is in oscillation just as the DNA's X-Ray shows.

[@iseecheese]

so returning has to be in a different space, but u cant change time without changin space to return u have to return to both perfectly, or u dont really complete the circle back, so if the split in to the circle path takes longer than a micromoment you'd die before either straight or circle path can happen, am i wrong? but if in a microsec ur photons /protons move still wouldnt be fast enough to get out of the way but if you could then you creat 2 of you so then which one goes which direction?

[@mknomad5]

Wait, how does he disqualify the third option, which is the "Sound of Thunder" option, which operates on the 'butterfly effect'? IMO this option does not necessarily include transversing to an "alternate universe". An 'alternate universe' implies a totally different universe, a parallel one, thus de facto disqualifying the option of altering the existing universe. I would not disqualify this option so neatly and easily, and I do not accept that disqualification, nor did I see explanation of it.

[@StephenGillie]

47:20 It's not that going faster than the speed of light lets you go backwards in time - it's that the speed of light is the fastest you can go *without* going backwards in time. That is to say that if light moved any faster, it would be moving slower. Like being at the North Pole on Earth - any direction is south.

[@zuhairyassin505]

love the sense of humor he has

[@StephenPaulKing]

1:00 - ... this seems to imply that TT communication can only occur if plausible deniability is allowed!

[@VanDammesCokeDealer]

I don't know, I personally always like when they talk about the paradoxes, although granted he didn't say anything I haven't heard before (except to distill all of them down to two unique paradoxes). Plus it was only the first 1/3 or less of the lecture, he got into the nuts and bolts after that. I guess if you're a physics student or an actual physicist it might have been somewhat boring, but I enjoyed it.

[@davidwilkie9551]

From the proposition of the universe as a Quantum Computation, ie the reality of existence is a standing wave in which the past and future are every side of now as potential inherent in the incidental structure, the incident connection of the kind modeled in Analog computers, then the central point of time is fixed now and forever. The architecture is implied by cyclic reflection, of which the simplest form/dominant probability, is a spectrum of resonance, part of which Astronomy studies. The flow of information past to future and future to where the past was when reflection of the information now shaped the present, is contained in virtual continuity of the kind that is mathematical. Time travel is just travel across the combinations of the information spectrum that is the apparent physical structure of the universe, the "architecture". But don't let any of the process ruin a good story, proving something wrong can reveal what is right some-times, (the probabilistic stability of shaped waves of QM).

[@deandeann1541]

You're not making sense.

[@thecuriousquest]

With the interactions, can we not transfer knowledge to those we visit, influencing their decision making?

[@ZiplineShazam]

Dash Rip Rock played Buddy Holly's "Not Fade Away" at The Grant Street Dance Hall in Lafayette, La. in the year 1989 . . .and it was Euphoric.

[@ensonhaber24]

I loved his explanations.

[@stevenos100]

4 momentum motors for a plane momentum - 1 forward 1 back pulsed accelerator motor - Q up a van der graff generator - move it and it creates it's own O(magnetism) = on an F-14 or something like that

[@MrFancyPenguin]

The thing about time is, everyone seems to assume that time is a linear progression of case to effect, but if you look at it from a non-linear non-subjective point of view, time is really a big ball of wibbly wobbly...... Time....-ey wimey...... Stuff!

[@jamesweldon6428]

I have a question? If anyone went back to the past and changed it. would not the the memory of those connected to all that changed be adjusted and what first had happened before the change be seen as a false scenario or imagined event. .

[@VanteStyle]

Wow. If I could go back in time and not watch this...

[@AnandKulkarniPlusOne]

10:29 - Primer ♥️

[@JackSarfatti]

Seth Lloyd of MIT in his video on time travel says that the memory of the future is erased in the time traveler's mind when he exists the time machine wormhole star gate in the past - in David Deutsch's many-worlds theory D-CTC model, but not in the P-CTC single-world model. There are also claims of super-computation in the D-CTC theory. The nonlinearity and non-unitarity should allow the future memories to be preserved as they allegedly are in Seth Lloyd's post-selected (Aharonov) P-CTC which may be equivalent to my back-reaction post-quantum Bohm pilot wave theory.

[@eXtremeDR]

So movement slower than light = forward in time while movement faster than light = backward in time. Does time stand still when moving exactly at the speed of light? And what happens at a state with no movement at all?

[@Slav4o911]

You did answer your own question. Actually the state with no movement should be the speed of light, because everything is moving relative to it but the speed of light is a constant. The light is not moving, the universe is moving, even time is frozen at the speed of light.

[@Leto85]

But if time is frozen at the speed of light, how can it be 'unfrozen' to travel with another speed when it is frozen? How should it (for the lack of a better word) be pushed to get into movement? I am asking this because if something travels at exactly the speed of light it can not go faster nor slower by itself, as far as I know.

[@eXtremeDR]

Leto85 Slower is no problem, e.g. speed of light underwater is approx. 25% slower. And KZbin: *How Scientists Stopped Light* So the speed of light is relative too. The problem with FTL speed is: Anything that actually moves faster than light (from a relative point of view) becomes invisible because....? Honestly I still have trouble to understand the concept of light. Light itself is invisible but it illuminates everything it hits (well, and the source is visible). It's a wave until it hits something but if light is a wave then how can it travel through empty space? A wave is not matter, its motion of matter. Like any other electromagnetic wave it can be canceled out as long as it didn't hit something.

[@Leto85]

***** Yes, it's a difficult subject indeed. And it seems to contradict itself on multiple occasion too. I have to get my notes on the subject to rewrap my brain around it though, but thanks for the answer. It was interesting to read nontheless. :)

[@WorthlessWinner]

i've heard physicists say that, if you move at the speed of light, the journey seems to happen instantly from your perspective (no time has taken place between setting off and getting the destination no matter how far you go). So time would stand still for you, even if you seem to be going at the speed of light to everyone else.

[@mariosmanesis8376]

very good information thanks

[@jamesweldon6428]

cheers. I will have a look at it

[@juanmedrano2616]

If you go faster then the speed of light you do not go back in time. Rather what you achieve is the slowing down of other particles (conservation of energy) that go back into close time loops separated from whatever engineering feat you did to achieve that.

[@MazDelaCerna]

Glad I found this!

[@Gromwald4178]

Susan Blackmore and Seth Lloyd are profiles on my website Benji Bear and Friends.

[@seethrupanti]

Is he professor for quantim mechanics or mechanical engineering?

[@Baraquiel62]

Love this video greets from Mexico City..

[@1infiniteloopend]

over 60k views... you all give me hope in humanity

[@jamesweldon6428]

my only answer to traveling back in time and making changes. would be creating parallel universes that hold the changes and returning back to the new universe to be effective. .

[@inhocsignovinces4512]

The final countdown! Great time travel movie 😀

[@TheLoneace69]

What is a time light spiral? Could these curves be segments of a spiral?

[@that1stupidkid613]

If you left a footprint in the past, wouldn't that in fact change the future considering the footprint wasn't there before? So you would NOT be able to interact with the past at all if that were true, right?

[@lsl70]

Bald, 1/8 comb over, and a pony tail all in one. Somebody could spend an hour giving a lecture on that amazing hair style.

[@CinematicDestiny4K]

Can anyone recommend some good time travel content on KZbin? I’m interested in realistic discussion, it’s surprisingly hard to find anything more than a 4 minute “did you know?” videos about time travel. Thanks in advance if anyone sees this lol

[@douae3039]

PBS space time

[@STohme]

Very interesting. Thank you very much.

[@iearthos1980]

#QuantumMechanicsOfTimeTravel

[@MikeRoePhonicsMusic]

What's a KZbin video description?

[@LucidityOfReality]

Surely if there is ANY interference in the space/time continuum WILL create a paradox ?, and Quantum Physics points out that atoms affect each other regardless of distance does that relate to time ?.

[@HondaCivic20019]

So I have a theory in time traveling where after you go back, the plot at the time that you traveled will reset to it's original state so even if you kill your grandfather before he met his wife, it will not change anything because if you go back to the present time, the time that you go back into will reset to it's original state.

[@ironmaiden2063]

StarsDanceTV9 months ago Dr. Seth Lloyd, an MIT professor and self-described "quantum mechanic," describes the quantum mechanics behind time travel during a guest lecture at the Institute for Quantum Computing, University of Waterloo. Recorded on Nov. 4, 2010, this is the entire lecture entitled "Sending a Photon Backwards in Time." Dr. Lloyd also sat down for a one-on-one interview at IQC, during which he discusses the weirdness (and beautiful simplicity) of quantum mechanics, and the incredible importance of quantum information research. Excerpts from this interview are below: Seth Lloyd on Quantum Weirdness:

[@realmrkou]

You can't cause something to happen which you know not to be the case. Aka going back in time would be impossible or is it related to you reference frame?

[@iseecheese]

as soon as the 1st copy appears in straight foward time ud then have a quadrillion copies of yourself taking up more space then there is surface of the earth, in circle time if both go into the circle time then the same thing would happen but which would then make the circle a different circle timeline cause then 2 would return, then ud only have a cirle if the mechanism effected all clones equally or else some would & some wouldnt circle back or at various size circles for each one. am i wrong?

[@itzthatnobody]

What if U was a common variable using the grid theory in correspondence to knowledge and memory? That would support Deutsch's theory, and in turn would allow the theory to be more like a quantum channel.

[@williambrownjim]

He should talk about family guy time travel and how stewie created the universe, the univese created stewie, ect.

[@estuhyerh67ber7]

Yes, or what about spherically curved strings at the Planck scale? A grid that leaks gravity but also acts as a hyperdimensional membrane? It would fit nicely with other quantum aspects and supports it would Deutsch's theory.