The Arrow of Time and How to Reverse It

18.11.2020
311 556 Näkymät

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Ever wish you could travel backward in time and do things differently? Good news: the laws of physics seem to say traveling backward in time is the same as traveling forwards. So why do we seem to be stuck in this inexorable flow towards the future? It's time to begin our journey towards really understanding time.
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Written by Matt O'Dowd
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Kommentteja
  • What does fusion look like in reverse? Does physics says that would be the same, or even possible?

    johnsonmajejohnsonmaje3 tuntia sitten
  • Maybe time goes reverse. We just don't know it, as we have forgotten it. All memories of the future has gotten erased as time travels backwards. If all vectors are reversed then our brain will be affected as well. Maybe past present and future happens simultaneously, and time is omnidirectional, but we can only observe and make sense of it in one direction, which leads us to think that time only moves forwards. You could have travelled nth time to your 10 year old birthday, but each time you do, you would think that you are just turning 10 for the first time. any memories beyond that haven't existed as far as the 10year old you is concerned. If that is the case, we would not even know if we kept doing the same thing over and over again or if we are able to change something.

    quertbarbie62quertbarbie624 tuntia sitten
  • If time was going backwards, how could we even notice?

    UpAndOutUpAndOut4 tuntia sitten
  • Why does no one think about the probability that we are riding a wave through time that "started" (for lack of a better term) at the "Big Bang" and resulting in "time" expanding in all temporal "directions"? The physical (uni)multiverse being "predetermined" along with time as every and anything that could be is, and the conciousness creating the ability to "choose" which path we experience. This theory would seem to indicate that as the velocity of time as we know it "slows down", we may (at some point in the distant future) be able to move through time in the same way we currently move through space. (As well as a whole slew of other concepts that could break the mind! lol)

    R.A. DragonR.A. Dragon5 tuntia sitten
  • How do you get a lower zero than zero? Zero is zero, zero means nothing how do you get more nothing when you already have nothing 🤷‍♂️

    Nothing Is real!Nothing Is real!5 tuntia sitten
  • How many dimensions does Imaginary time have?

    Roddy RichRoddy Rich6 tuntia sitten
  • If someone actually found away to travel back in time. There are might be two or more options; 1. They are thrown back to the beginning of the universe. 2. The Quantum Multiverse interferes and puts them into another universe. Could anyone or Matt care to explain?

    Roddy RichRoddy Rich6 tuntia sitten
  • At 7:20 - Comparing a low entropy particle cluster to the compressed state of our early universe isn't a good analogy, is it? As I understand, space was uniformly dense everywhere in our early universe. It was just more dense than it is today. There was never a super dense volume of matter contained within a larger empty space. Correct me if I'm wrong.

    Johnwill KeatingJohnwill Keating7 tuntia sitten
  • I have a question. Do the anti particles use the same force carrier particles as regular particles? If not, are there anti photons carrying anti electromagnetic force?

    noaholtasnoaholtas9 tuntia sitten
  • What do you think of this new paper published only a few days ago? Physicists discover the 'Kings and Queens of Quantumness' | Space www.livescience.com/quantifying-quantumness.html

    Mike BrownMike Brown10 tuntia sitten
  • Would the universe exist if there was no one there to see it? :D

    Mister NobodyMister Nobody10 tuntia sitten
  • Time is not an arrow. It's now how we think of it or perceive it. It doesn't move "forward". Life isn't some video tape that can be rewound or fast forward. Life isn't linear, it's chaotic. The atoms around us are wiggling around randomly, it's our minds that create the illusion of order and structure. We're experiencing a randomness that we are simply accustomed to.

    Mad Mental HibbyMad Mental Hibby11 tuntia sitten
  • What if the universe bounces from big bang to big crunch and at each time a coin is flipped and the result is who win in the amount of matter vs antimatter, creating a symmetry between a matter universe and an antimatter universe?

    Guénaël SoumGuénaël Soum12 tuntia sitten
  • "Time flies like an arrow, Fruit flies like a banana." --Unknown author

    doliio volaydoliio volay13 tuntia sitten
  • Aliens 👽 are just humans travelling back in time!

    Callum BushCallum Bush16 tuntia sitten
  • Aren't there particles that break time symmetry, and are actually different going backwards than forwards? Veritasium did a video on this in 2017 called "This Particle Breaks Time Symmetry." I know I'm late, but I'd like it to be addressed.

    Mark ShimanMark Shiman16 tuntia sitten
  • If charge is an intrinsic property of matter , Why electron and proton have same amount of charge although their mass is different????

    Multiversal ExplorersMultiversal Explorers19 tuntia sitten
    • This is a great channel, that's why it would be very interesting to watch a video on this.

      doliio volaydoliio volay13 tuntia sitten
  • So, this video talks a lot about perfectly reversing the motion of particles. But similar to the Egg mentioned at the start, if time ran backwards, would we expect to see stars instantaneously turn Iron into Carbon, and then over a few weeks, turn the Carbon into oxygen, then lighter elements, all the way back to a hydrogen nebula? Would entropy increase by way of everything becoming a homogeneous hydrogen sea with stars being the great doomsday machines of that universe, and black (white?) holes spewing out new and complex matter?

    Chucky DickensChucky Dickens20 tuntia sitten
  • 🎵If you made a scrambled egg tonight, there'd be no return to yolk white. And when it's fried you can't turn it back to raw food that is the arrow of ENTROPIC TIME🎵

    Additional PylonAdditional Pylon22 tuntia sitten
  • I have a question. Is there any reason to believe that the fundamental forces of physocs could be anything other than what they are? There's a lot of talk of fine tuning and the anthropic principle, but I've never heard anyone explain why or how we think the "dials" could be set to anything else.

    Compelling SatanistCompelling Satanist22 tuntia sitten
  • I LOVED what you said about creating an illusion of understanding. I've seen so many people use words they don't understand to create a total BS argument....

    Kai M.F.S.Kai M.F.S.23 tuntia sitten
  • Could gravity simply be a manifestation of a physical deformity of 3-dimensional space into a fourth physical dimension, much as we could create a dimple of Flatland into a "downward" 3-D direction which is outside of the Flatlanders' field of view? Flatlanders would experience acceleration towards a dimple as we experience acceleration due to gravity. As one could move more quickly than otherwise possible between two points on Flatland via a 3-dimensional warp, could a 4-D warp of 3-D space possibly help explain the linkage between entangled particles? Would then a linkage between time and gravity (time slows down near a black hole's event horizon) - or is it rather a linkage between time and velocity (such as the lifetime of a muon in our frame of reference) - preclude or support such a notion of gravity simply being a 4-D curvature of our space, and time being something completely different and independent?

    jimmypalavijimmypalaviPäivä sitten
  • One of famous argument The author of general relativity, Puts a white glove in a wooden Box But I think specifically the middle One on the right is one empty box On the left is one empty box Solve This argument, when few could understand Einstein's explanation Is not as difficult to understand as some may consider But as a man of good will with good intentions would I want to share the mathematical assumption of this scientific thought experiment? I can't say I knew Einstein But I do comprehend how science could have really bad out comes. The problem is put simply Einstein withheld some comprehension for fear of its usage If a dimond of significant worth, that is not cubic zirconia, the density of matter that could be created could lead to compressed matter to the extent warping of gravity is accomplished Long distance space flights could require gravity the closest form of artificially generated gravity minded for our intentions is many many light years away. Electron is faster than light. © Steven Peter James Kyle ISBN: 14/03/1989

    steven kylesteven kylePäivä sitten
  • Matt O'Dowd, I disagree, if an instant occurrence of all matter reverseing, in the arrow of time, so including a clock that has wound backwards 5 minutes approximately as part of this anoamly in physics, but the clock ticks for 5 minutes into a new future, the 5 minutes wound backwards is lost forever untill time moves forward in an instant exactly to the time arrow where time went bacwards the arrow needs to be resset, as each tick forward is 1 tick lost over time for the purpose of moving backwards or fowards in time. Light equal 576 why? © Steven Peter James Kyle ISBN: 14/03/1989.

    steven kylesteven kylePäivä sitten
  • Nice Shirt

    Vincent ProxyVincent ProxyPäivä sitten
  • Love all your videos 🤩🤩

    Iam-Hanss AcostaIam-Hanss AcostaPäivä sitten
  • U look fit on that video lad!!!🥸

    Iam-Hanss AcostaIam-Hanss AcostaPäivä sitten
  • Why use entropy as the big hurdle? If I accept some part of “quantum“ uses the concept of “randomness”... reverse the arrow means roll the negative dice? What is “negative random”? How do you reverse a quantum random event? A+random=B... B-Random=A? The act of choosing a“random” value breaks this doesn’t it? If you can run the equation the same backwards or forward, what equals “negative dead/alive cat”?

    Ryan ChristophersonRyan ChristophersonPäivä sitten
  • I've been thinking about this (5:11) these past few days. Life, in a way, is a region of space with low entropy fighting against the thermodynamic-compliant rest of the universe trying to disperse it's energy and increase it's entropy. Since that is a basic requirement for life, then in a time-reversed universe wouldn't life operate in the "opposite" way, being a region of space fighting to increase it's entropy against the rest of the time-reversed universe? We know our consciousness emerges in our universe of increasing entropy, so maybe consciousness is emergent specifically in this direction. That would mean that a consciousness should perceive time as going "forward" regardless of the type of arrow of time of their universe. Better yet, time wouldn't need to flow at all. Maybe it is just another static dimension, and consciousness only emerges when moving through time in a direction of increasing entropy, so it would always perceive as if time itself was flowing, and it was being carried along with it.

    agar32agar32Päivä sitten
  • Is it possible that imagining the future is equivalent to remembering the past in a time reversed universe?

    ccvchargerccvchargerPäivä sitten
  • How do you separate or distinguish time from light/energy? Or for our current understanding are they inseparable ?

    Brent BayBrent BayPäivä sitten
  • What do you think of scientists like Eric Lerner and many others, who keep pointing out that the Big Bang theory itself is unfounded, it keeps failing with its numerous predictions and leads to an always increasing number of further assumptions and exotic hypothetical entities, e.g. inflation, dark energy and dark matter? Apparently, Hubble himself did not believe in an expanding universe and in the Big Bang theory. Eric Lerner explains that all observations can be explained without the expanded universe, except for the redshift, which can be explained in other way as well, without requiring such an extreme amount of additional assumptions. If this is true, then this cannot be ignored. A lot of these scientists advocate the plasma universe theory, as an alternative to Big Bang, although whether plasma cosmology is true or not, seems rather another question. They also affirm a huge bias of the scientific community towards the established paradigm and lack of proper questioning of numerous observations. It's also hard to argue that the world is plenty of biases, manipulations and mainstream lobbies. I am no expert, but reading a few articles about it and watching a few scientific videos, made me more aware and question a bit the validity and an almost unanimous acceptance of the Big Bang theory, despite indeed its leading to many incomprehensible assumptions, such as inflation. This is a great channel, that's why it would be very interesting to watch a video on this.

    Flamma2512Flamma2512Päivä sitten
  • I'm sad that the Conway's game of life cameo isn't getting more attention. :-(

    Benjamin ShropshireBenjamin ShropshirePäivä sitten
  • Does the release of the new World of Warcraft expansion have anything to do with the timing of your release break? :P

    Alex ChongAlex ChongPäivä sitten
  • because there is no time, "arrow of time" is simply entropy in action. you can't reverse time because you can't reverse entropy.

    HamHamPäivä sitten
  • 1:08 to 1:10 Can we just appreciate how realistic that aging effect looked?

    Albert JackinsonAlbert JackinsonPäivä sitten
  • The clock is always ticking

    CosmicCosmicPäivä sitten
  • Great video 👍🛸

    Jhause 9Jhause 9Päivä sitten
  • This one is a Super Sleeper. This is 5th time I'm trying to watch this video.

    Jais MathewsJais MathewsPäivä sitten
  • "since entropy can occasionally decrease locally, i.e. particle trajectories converging, then entropy could conceivably drop on such a large scale so as to assemble an entire universe." Ok, we are talking about not only a gross violation of the second LAW of thermodynamics, but arguably the most improbable thing conceivable - far more inconceivable than witnessing a reversal of time itself. To make things more relatable, the probably of such a thing happening is infinitely more improbable than such miraculous events as 1) a river suddenly reversing course 2) a broken vase spontaneously reassembling and jumping back up to the shelf from which it fell 3) a sand castle destroyed by pounding surf suddenly being reformed by waves 4) a decaying corpse suddenly getting better, etc. We need to take a moment to consider the mind-numbingly-stupidly low probability of such an event. Scientists are fond of invoking such entropy fluctuations to explain the supposed origin or evolution of the universe. We observe the arrow of time because no entropic fluctuation large enough to amount to anything significant has ever been observed. And any suggestion that such an event will ever occur is as outrageous as suggesting that time will spontaneously reverse. Such things may be possible but the faith required to believe them rivals any religious explanation for science.

    Ben RudolphBen RudolphPäivä sitten
  • Think about it from a quantum mechanical point of view, if we reverse the arrow of time, we will just play the schrödinger equation backwards, But the results of our observations will still be probabilistic and not be the same events played in reverse order. In short, there is no "reversal of time", Only evolution of probabilities.

    Svend KorsgaardSvend KorsgaardPäivä sitten
  • Hey Matt, would you consider touching the question about if the time dimension, t, even exists in the first place? No I don't mean the passage of time or how we experience it by our brain and senses nor that the universe is a 4th dimension static block. I actually mean, the time as the fourth dimension. Does that fourth dimension actually exists and is a part of the universe and reality? In other words, what is it about time, the t variable, that makes it absolutely necessary to be included in to the equations of modern theories? Is there perhaps, a possibility that those equations be written instead without the t variable at all and still work? If a theory can be written down, without using the t variable, and still work, wouldn't that prove that t is redundant and imaginary? Also the fact that quantum physics work entirely without the DIRECTION of t (the arrow of time) and on top of that it is actually impossible to define that directionality in QM (as QM stands now), isn't that a good enough indication for t being just a useful concept and not really representative of any physical part of reality? First and foremost, there is no satisfying definition of what t is. None that I know of. some claim, that in order for 2 parties to meet at a point in our universe, it requires 4 different coordinates, the three x, y, z and a fourth one the t. Well, I can easily demonstrate, that this is not the case. Actually, only the first 3 coordinates are needed. The fourth one is not needed, at all. All it requires, is an agreement for both parties, to start moving, upon a third party event or signal, or even better yet, the random decay of an atom! And they indeed, will eventually meet at that 3 dimensional point. Therefore, no fourth coordinate was required for this and therefore it is not needed, at all. The agreement between the parties, about the signal, is not a coordinate, and cannot be considered as such. In fact I just used a completely random event instead, which is the exact opposite of a coordinate! Most go by the definition that Einstein haves it, in order to move forward with his theories and just defined it as "what the clocks measure". This "definition", is a circucal logical fallacy that just begs the question. It is far from satisfying, it is actually a fallacy. How can we base our entire physics and science, on a... Logical fallacy? What is really the undoubtable reason, for the absolute necessity of the t dimension? I can't give any answer to that. There seems to be none, but the insistence on using it feverously on GR theories by all scientists, blows my mind. I struggle thinking, because there must be a reason that all those scientists take t as granted and real. So, what is this reason?

    John KJohn KPäivä sitten
  • you getting older

    E ZE ZPäivä sitten
  • But does this not mean that entropy does not always ends up in higher states but rather fluctuate or is a sort of a wave function going between high and low? If low entropy in “current” state both in “past” and “future” ends up high, a high entropy should equally end up as a low.

    Niels PedersenNiels PedersenPäivä sitten
  • If there were supersymmetry; there's not. Reversing particles is not time reversal either. You cant reverse the change of particles.

    Alliance News NetworkAlliance News NetworkPäivä sitten
  • I have a question (full disclosure, I'm not a mathematician nor a physicist ... not even close). Is there a proof or theory or experiment that shows the Heisenberg uncertainty principle is symmetric for time? Asked another way, what are the effects of the Heisenberg uncertainty principle (which generates chaotic effects in the "forward direction of time") when those equations are "run backwards in time"? That is, we know there are challenges predicting the future position/momentum of the atoms running forwards in time ... and the longer you run the computations the more the predictions become chaotic. So how do we know that running the same equations backwards will result in "particles retracing their footsteps" given the same quantum effects/fluctuations/uncertainty?

    Don CloudDon CloudPäivä sitten
  • Cannot reverse quantum interactions because they're probabilistic, momentum & location together being uncertain --> time's arrow

    Jezza MobileJezza MobilePäivä sitten
  • Q.E.D... Good one!

    Patrik WihlkePatrik WihlkePäivä sitten
  • Obviously this vid isn’t directly talking about Blackholes but your general expertise - you would make a great consultant on the Disney remake of ‘The Blackhole.’

    Sugar Rush Times 2030Sugar Rush Times 2030Päivä sitten
    • Excuse me ‘The Black Hole.’

      Sugar Rush Times 2030Sugar Rush Times 2030Päivä sitten
  • I'm going to try and ask this question to the best of my ability: In space-time, we always talk about the arrow of time either pointing forwards or backwards. If we were to introduce a black hole, and enough energy to magically pass through the event horizon unharmed we could enter a place where time and space is flipped... My question is, in Time-Space, what would the arrow of time look like where we would now *not only* be able to travel back and forth through time - but left and right, and up and down as well?

    Untitled DocumentUntitled DocumentPäivä sitten
  • How would a universe "before" the big bang that is time reversed be distinguishable from our universe? If physics don't care about the arrow of time, shouldn't it be indistinguishable? Just flip the diagram a random couple of times and you're lost.

    DevalishDevalishPäivä sitten
  • Have they found fart matter yet before you talk about "arrow of time"? Metaphysics and pseudoscience garbage mix; too much fancy terms and nonsensical math does not mean science.

    Big Bang Theology Is A FallacyBig Bang Theology Is A FallacyPäivä sitten
  • Interference fringes require all possible paths at the same time. Time is all possible paths of causality. Entanglement is when we cause two particles to share the same spot in spacetime ..they shared all possible paths for a split second. Tunneling can happen because the wave is coherent and has access to all possible paths.

    pittsburghjoepittsburghjoePäivä sitten
  • Would travelling back in time not also require travelling forward for it to be meaningful? If in one moment we were in the present and in the next we were in the past then our travel is still forward in time, as opposed to time just playing out backwards and we get younger...?

    Bexley75Bexley75Päivä sitten
  • I have a curiosity. If space and time are components of the same structure (the space time) and the space is expanding, shouldn't the time also be expanding? I heard about time dilatation due to relativity, but never heard about time expanding in a whole like the space.

    Guilherme SanchesGuilherme SanchesPäivä sitten
  • So, the spacetime could have a Pendulum behaviour with the Big Bang at the center of time dimension. Could the "backward" direction be the thing we call "an antimatter universe"? The temperature should be the "force" (or it's manifestation) that choose the direction, under the 0 kelvin degrees matter become antimatter. But the other question is: how could a so cold universe exist? The temperature should increase again going backward. Like having 2 big bangs at the 2 poles instead of one in the center. But, again, if we suppose this, the concept of time travel or antimatter world are wrong again. Or are just... Relative to our direction?

    Davide AllegrucciDavide AllegrucciPäivä sitten
  • How can time stop at event horizon, cause force and movement can only occur if time is moving and in black holes gravitational waves are at work and also at outside layers hawking radiation is being emitted which is proven than how can time stop please answer

    Chinese VirusChinese VirusPäivä sitten
  • So does this mean living beings all possess free will? They don’t have to obey the entropy of particles, just homeostasis, do they become “particles” in a system that can be traced just as easily forwards and backwards through time?

    Mediocre MediaMediocre MediaPäivä sitten
  • U know. Anant anantum ishwar narayan.

    Diwitdhar TripathiDiwitdhar TripathiPäivä sitten
  • God's realms.

    Diwitdhar TripathiDiwitdhar TripathiPäivä sitten
  • The God's power.

    Diwitdhar TripathiDiwitdhar TripathiPäivä sitten
  • Backward.

    Diwitdhar TripathiDiwitdhar TripathiPäivä sitten
  • I'm wondering how does friction play into this. Because friction is highly dependent on the direction of motion, if we reverse time, the motion of an object affected by friction will vary greatly from its motion when the time is going forwards.

    TheDamian58CTheDamian58CPäivä sitten
  • Cool t shirt!

    kind kenderkind kender2 päivää sitten
  • Since gravity and time are so heavily entwined. Wouldn't the reversal of time also reverse the effect of gravity? As in blast the planet apart.

    Cainz JussCainz Juss2 päivää sitten
  • Everytime i wish i could travel back!

    Burton PierreBurton Pierre2 päivää sitten
  • Perhaps, as I’ve been told relentlessly since high school, the Big Bang was immediately preceded by an absolute entropy minimum throughout the multiverse... ...or... ...perhaps it was preceded by an immensely improbable LOCALIZED entropy minimum within that minuscule slice of the universe knowable to us. Don’t forget, friends, immensely improbable multiplied by a mind-bogglingly expansive duration of time equals completely inevitable! Just sayin’ You’re going to give me an argument. You’re going to say I’m crazy. You’re going to ask, “How many PhD’s in Physics did you argue past MIT thesis juries while you were driving a taxicab out in the suburbs for thirty five years?” Alright. Alright. Have to admit you’ve got a point there ... but, as the eminent George W. Bush once remarked about the Theory of Natural Selection one day while he was exiting the Little Boy’s Room: “The jury is still out on that one. A theory’s just a hunch. Darwin had a hunch, you have a hunch, I have a hunch - but God’s gonna get the last laugh on all of us, just you mark my words.” Answer that, smart guy! We’re talking about the President of the United States, here. Not just some rando FIworldr. After all, how many electoral votes has Roger Penrose ever won? Think about that, huh. So, maybe those “scientists” in their “universities” are clever enough to have a better hunch than God... ...or... ...just maybe you might one day find yourself on the OTHER side of the Big Bang, heading backwards in time. Don’t be surprised if you’re on hand to see Marty McFly teach Chuck Berry how to play “Johnny B Goode”. Mark my words!

    Paul the Audacious BradfordPaul the Audacious Bradford2 päivää sitten
  • A key realization is that fundamental particle interactions are reversible, and should be, intuitively, "as if viewed on film". Once you proceed to bulk particles, however, you no longer get perfectly elastic collisions or reversible interactions zoomed out to that bulk scale. I guess this is another way of saying that, in no sequence or reality would the egg ever "un-smash" itself. A thought on some of the comments -- if all forces are eventually hoped to be unified, and gravity truly turns out to be a pseudo-force as it really appears to be in many cases, would it be possible that all forces are actually pseudo- forces. To me, it has always seemed that electrons in orbitals are merely following geodesics of their own kind -- in their own, curved spacetime.

    onehit pickonehit pick2 päivää sitten
  • Matt O’Dowd ... you be schmaaaahht!

    Paul the Audacious BradfordPaul the Audacious Bradford2 päivää sitten
  • plot twist, humans meet an alien species, and they are going backwards in time so it's very hard to interact.

    JeacomJeacom2 päivää sitten
  • Ah, arrows of time. The title of the third book in Greg Egan's _Orthogonal_ trilogy. Some rather weird things happen when encountering things with arrows of time going in different directions. Reverse your arrow of time and you can land on an antimatter planet like it's normal, but with the planet's arrow of time still pointing opposite to yours you can't grow plants in its soil.

    Roxor128Roxor1282 päivää sitten
  • If the time is 0 at the event horizon then does that mean anything at event horizon is in a quantum superposition state and escaping the event horizon would take it to parallel universe?

    Rajiv BediRajiv Bedi2 päivää sitten
  • i hope that time video explains what ive been thinking

    RaezoresRaezores2 päivää sitten
  • in a way to me you guys are ghosts.. because using thought i can travel faster than light and see MLKjr speaking but with very few photons so back tracing all the photons leads back to him but the ghost of the past and "reversing" time.. i cant see things that happen inside buildings because the light doesnt escape.. it hits the walls inside them and they appears as black cubes.. basically i can see where the sun shines. or im part of the cmb because i can catch up.

    RaezoresRaezores2 päivää sitten
  • How does time reversibility fit in with CPT symmetry, since it's been shown that CP (and therefore T) symmetry can be broken for certain processes? Is this a separate conception of time?

    TealquoiseTealquoise2 päivää sitten
  • Where does time come from?

    Seekthetruth3000Seekthetruth30002 päivää sitten
  • Does time flow forward or backward at the center (singularity) of a black hole?

    Mr. KentMr. Kent2 päivää sitten
  • how about this, the ´´2nd´´ universe comes into existence every, lets say.. ´´plank second´´. just like our universe. we cant ever ´´ see ´´ each other, because our time flows purpendicular. but we exist together in the eternal now.

    Wim TerminatorWim Terminator2 päivää sitten
  • So because of time we’re stuck in a 2d world? Like we can only view it through individual slices instead of all at once? Time makes the universe like a CT or MRI scan?

    Xan OstlerXan Ostler2 päivää sitten
  • ads before video. downvoted and reported

    nig‎ger_google_is_a_bad compan‎ynig‎ger_google_is_a_bad compan‎y2 päivää sitten
  • Put a monkey in front of a typewriter and let him hit the keyboard randomly. If you give him infinite time, he WILL write Hamlet from the beginning to the end at some point...it's a mathematical certainty. In fact, he will randomly write every book ever written. Entropy grows with time, but give infinite time to any system and the opposite will happen : chaos will turn into order.

    Frank MaclowFrank Maclow2 päivää sitten
  • You’re so pseudoscience! Pretty ridiculous. Tha fact that I store data inside a computer database, doesn’t means nor implies: “history, in reality , is just a collection of binary states recorded in a physical medium made of Fe alloy”. You people are nuts for being published. lol

    Sugar JunkySugar Junky2 päivää sitten
  • Before you do anything to harm yourself (in the future) talk to me first

    Nilstro BaggiaNilstro Baggia2 päivää sitten
  • BEST. ENDING. EVER.

    Diana GibbsDiana Gibbs2 päivää sitten
  • Free will? 😅

    Pablo PinedaPablo Pineda2 päivää sitten
  • Tenet?

    Pablo PinedaPablo Pineda2 päivää sitten
  • Wat

    Axel FoleyAxel Foley2 päivää sitten
  • If you were to strike a neutron star like an anvil with a hammer. Can the sound wave propagating through the neutron star exceed the speed of light because of the stars density? Is it possible to hear the echo before you strike the anvil?

    The Riddle Of SteelThe Riddle Of Steel2 päivää sitten
  • That in the increasing entropy of our universe, our solar system and our Earth and all of the life on it, formed---is startling!

    Sharyn GuthrieSharyn Guthrie2 päivää sitten
  • What I don't get with the explanation based on the "cosmic" arrow of time caused by the low-entropy big bang is how this "macro" arrow can transfer to our human-scale phenomena like eggs breaking apart, which don't seem to be connected to the large scale.

    Salvador BayarriSalvador Bayarri2 päivää sitten
  • Does this mean poop would go back up my butt?

    Mark thebldrMark thebldr2 päivää sitten
  • Seems even the rate of flow of time is relative. Time is observed to be moving slowly on objects moving very fast and objects near a massive body. But the system with the massive body could be moving away very fast with respect to another object. So rate of flow of time will be different for everybody except for all objects at any event horizon where it will trickle to zero. Also time will appear to flow exceedingly fast at something that appears stationary from a fast moving body like Earth which is hurtling through space with incredible velocities. Also velocities are also relative depending on the direction of motions of all the objects relative to each other. So there is no fixed rate of flow of time anywhere. So where would the flow flow of time become infinitely fast ???????

    John LeeJohn Lee2 päivää sitten
  • I literally need the next episode yesterday.

    foreverthechallengersforeverthechallengers2 päivää sitten
  • Who says time moves forward? That's a pretty big assumption

    michael lmichael l2 päivää sitten
  • Assuming the universe has a boundary, would the regions beyond said boundary/observable universe also be in the same state of a singularity?

    Frikkie 92Frikkie 922 päivää sitten
  • There are no time, there are just space! Time are illusion! It point toword gradient of density in that "hyperspace"!

    Alex BrainAlex Brain2 päivää sitten
  • fiworld.info/tools/3g_Rc6wh26lV-bzc1-MV2Q.html

    Rose WarRose War2 päivää sitten
  • I understand the QED joke now!!! Thanks, Calc III professor, for telling us how to end a proof.

    ErikErik2 päivää sitten
  • The fundamental limits of Laws of Nature being that the equations are a human construction written in a human language of which the physical universe isn't beholden. Indeed, science isn't about absolutes, but a method of gathering empirical knowledge. ANY physics equation comes with assumptions after all (when applied to reality). Human assumptions made form a human perspective. But we can use them to create truths within a specific context: Equations (of which reality is not beholden). That rates of change are effected by mass seems irrefutable, to assume that means some dimension called time is being traversed more slowly or faster is a stretch of the imagination of which there is no empirical evidence to support, there is no Law of Time even. It's a fun thing to say that if you were omniscient you could use equations to trace everything back to some "beginning". Causing the universe to do such a thing would take more than omniscience no doubt, omnipotence might be more suited to this task. Then again, even that might not be enough if time were merely an illusion of the human perspective, but omniscience might enlighten one to that reality. Yet, I doubt ANY human will ever be omniscient or omnipotent. Human condition and all. Equations are tools, separate from the reality we use them to attempt to describe. Useful, but only beautiful in the minds of the beholders. Human imagination is a powerful thing & what I believe set Einstein apart from people who were better at equations than he was. He was able to look at the available data and create an explanation that predicted the things he saw no matter how absurd it seemed. Just because they work though, that doesn't mean assumptions weren't made... I mean, his equations do predict situations were "infinite" is a thing. Not ideal, to say the least. EVERYTHING is relative from the human perspective, from the moment we are born to the day we die, it's shouldn't be shocking that we use relativity to explain the world around us then, right?

    Science!Science!2 päivää sitten
  • Yes, Some times we can remember the future they call that: Déjà vu

    Luis BarriosLuis Barrios2 päivää sitten
    • @Chinese Virus Within the movie Matrix, déjà vu is the repetition of an event that had already taken place in the "future" (time does not exist) Such as a video game where we already play that level but the characters acquire a momentary awareness that they should have forgotten restart a new game when it happens The matrix code is modified. In The Matrix, Neo sees a black cat walking followed by another that behaves in exactly the same way. due to a matrix failure

      Luis BarriosLuis BarriosPäivä sitten
    • Recall what déjà vu actually is

      Chinese VirusChinese VirusPäivä sitten
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