Home / Curious Mind / Time Might Not Reverse Like Physicists Thought, Here’s Why

Time Might Not Reverse Like Physicists Thought, Here’s Why

Using black holes as their models, an international team of researchers has found that if three or more objects move around each other, history cannot be reversed.
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Historically, scientists have had to rely on statistical arguments based on increasing entropy to explain why time only moves in one direction.

Until now.

Researchers believe they have demonstrated that fundamentally time cannot be turned backwards in all cases because things don’t always happen the same way in reverse.

The researchers came to this conclusion after simulating the dance of three orbiting black holes. By running the simulation in reverse, they found that time can’t be reversed in 5% of the calculations.

Find out more about these 3 simulated black holes, how they broke the symmetry of time, and how this discovery may shape our understanding of the basic laws of nature in this Elements.

#physics #blackholes #time #simulation #seeker #science #Elements

Read More:

Why Does Time Go Forward Instead of Backward?

“Most of the laws of physics, like gravity and quantum mechanics, are symmetric with respect to time. That means that it doesn’t matter whether time moves forward or backwards. If time ran in reverse, all the laws of physics would work the same. That is, all the laws except one.”

How Gravity Explains Why Time Never Runs Backward

“If time’s arrow follows the increase of entropy, and if the entropy in the universe is always increasing, then it means that at some point in the past, entropy must have been low. Therein lies the puzzle: why was the universe in such a low entropy state in the first place?”

Can Time go Backward?

“t seems intuitively plausible that it can, but the concept creates a variety of paradoxes. For example, a time-reversed galaxy would be invisible to us because light would flow into it instead of out.”

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About Moin Uddin Ahmed Tipu

My name is Moin Uddin Ahmed Tipu. I`m a Google AdSense Professional and a Google Certified AdSense Optimizer. Life Doesn't Have CTRL + Z. You Can't Undo Lot Of Things. One Of Them Can Be Wrong Selection. Before You Proceed, Make Sure It Will Be Good For You.

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  1. Avatar

    Q: is there a theory about "Time Friction"? The possiblity that time has a great physical force behind it? So the idea that doing back through time or against times flow would be akin to throwing a pebble up a raging river while still under water?

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    NASA scientists detect evidence of parallel universe where time runs backwards.

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    its impossible to get random so this result makes sense

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    Tanjimul chowdhury

    That means reality exists even beyond planc length. We could be a simulation after all

  5. Avatar
    Ricardo González

    Great video!

  6. Avatar
    Christina Jean

    If you want to learn more about three body problem you can check this video from PBS space time : https://m.youtube.com/watch?v=et7XvBenEo8

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    This helps to debunk one of the few arguments against simulation theory: reversible time.

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    entropy will increase no matter the direction of time flow

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    Now that i think about it… at planck’s scale, wouldn’t we need a quantum gravity theory, which we currently don’t have? Even if there is no rounding problem, it just proves that our current understanding of gravity is not complete.

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    Seeker: Time CANNOT go in reverse ever, just no possible not even in a parallel universe.

    NASA: Hold my beer 🍺

  11. Avatar

    Four days after this video nasa finds evidence for a parellel universe where time moves backwards

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    Couldn't that also prove that time has more than one dimension, rather than that reversing time is impossible. There could also be unknown variables that affect the simulation as well and The Heisenberg Uncertainty Principle is always a factor to take into consideration, since they're testing more than one variable.

    Actually I'd say that entropy is the bigger issue with time travel. Since the entropy of a system never decreases it would be impossible to travel to a time with a lower entropy.

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    May 20, 2020: NASA claims there is a parallel universe where time runs in reverse?!?!?

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    James Greene III

    I’m just here after watching the tenant trailer lol

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    Did they also run it forward and predict with 100% accuracy what the next positions would be?
    (If could not then shouldn't their logical conclusion be that time can't flow forward?)

  16. Avatar

    I came here after seeing Tenet trailer

  17. Avatar

    Humans assume we can measure everything using algebra but some numbers are too small and too big.

  18. Avatar

    now I can watch TENET

  19. Avatar
    Praneel Acharya

    It has been said that something as small as the flutter of a butterfly wing can cause a typhoon halfway around the world.

  20. Avatar
    Charli Damelio

    say that to nasa who just discovered the parallel universe😂

  21. Avatar

    I just have one strange thought… at the beginning of the video you say you can’t remember the future but I have dreams of the future all the time that definitely come true.

  22. Avatar

    Whos here after watching new Tenet Trailer?

  23. Avatar

    NASA in Hebrew means "To Decieve"
    Don't believe anything they say.

  24. Avatar

    I think all these comments misunderstand the experiment and I’m not sure seeker understands or explained it clearly. I think what the researchers did was purposefully inject errors or random perturbations on then order of 10 to the -100 and watch the orbits. Their premise is that even if time is reversed the universe has random perturbations on the order of the Planck length which are not predictable. I guess they are asserting that even if you can reverse time you cant reverse random quantum events. Those random events will eventually lead to macro level changes in the orbits.

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    Light & Molecules

    Does anyone know the reference for this 3-body problem discussed in the video? I couldn't find it in the description.

  26. Avatar

    The question I have is why do science YouTubers seem to have the same shelving in their backgrounds?

  27. Avatar

    There is only now. Time goes neither backward nor forward. Everything happens at one point.

  28. Avatar
    Yassine Meslouhi


  29. Avatar

    No object in the Universe can be in the same place in the Universe more than once

  30. Avatar

    When you turn back time the direction of the forces changes as well

  31. Avatar
    Jbrownjetmech -

    So, reality is not quantized discretely enough to be able to retrace its own steps?

  32. Avatar

    "The fault, dear Brutus, is not in our stars  But in ourselves, that we are underlings."….. I think this is why they named it "Brutus".

  33. Avatar

    I'm a noob, but can it be something to do with the probability of quanta? Like there's a probability that one of the electrons in the computer could appear on Jupiter messing up the simulation?

  34. Avatar

    Computer is absolutely deterministic system. If starting data and architecture of computer didn't change, then ending data is always the same. They make some mistake.

  35. Avatar

    xD then we dont realized that our time is moving backwards also forward
    If the mirror universe is reversed time then basically we are moving backwards and forward at the same time.
    We just dont know.

  36. Avatar

    Your eye direct is too low. Its easy to see the screen in your glasses and your eyeline is below two thirds screen.

  37. Avatar

    If our calculations are wrong and the arrow of time cannot be reversed, either a)our equations are wrong or b)time isn't really moving.

  38. Avatar

    Orbits don't really illustrate the problem for me. I don't see how cause & effect could be in reverse order. Since, for instance, sand castles crumble according to the force of gravity acting on sand grains, how could sand grains defy gravity to assemble into sand castles, yet still be on a planet, in a universe otherwise obeying the law of gravity as we understand it, with predictable orbits, tides, falling objects, etc, but in reverse? Simply reversing time would require distinct laws to be effecting each phenomenon, rather than one law explaining both.

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    Christian Kenyon

    You want the answer? Gotta kill me first nigguh

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  42. Avatar

    I don't buy it. In any simulation, there will always be rounding errors that cannot be accounted for. The "run in reverse" thing did not work because of these errors.

  43. Avatar

    you look like you just got done with a jog! Clean them glasses!

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