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Science

Gravity: We Might Have Been Getting It Wrong This Whole Time (phys.org) 152

Motoko Kakubayashi, from the Kavli Institute for the Physics and Mathematics of the Universe, writes via Phys.org: Physicists have been looking for laws that explain both the microscopic world of elementary particles and the macroscopic world of the universe and the Big Bang at its beginning, expecting that such fundamental laws should have symmetry in all circumstances. However, last year, two physicists found a theoretical proof that, at the most fundamental level, nature does not respect symmetry. There are four fundamental forces in the physical world: electromagnetism, strong force, weak force, and gravity. Gravity is the only force still unexplainable at the quantum level. Its effects on big objects, such as planets or stars, are relatively easy to see, but things get complicated when one tries to understand gravity in the small world of elementary particles.

To try to understand gravity on the quantum level, Hirosi Ooguri, the director of the Kavli Institute for the Physics and Mathematics of the Universe in Tokyo, and Daniel Harlow, an assistant professor at the Massachusetts Institute of Technology, started with the holographic principle. This principle explains three-dimensional phenomena influenced by gravity on a two-dimensional flat space that is not influenced by gravity. This is not a real representation of our universe, but it is close enough to help researchers study its basic aspects. The pair then showed how quantum error correcting codes, which explain how three-dimensional gravitational phenomena pop out from two dimensions, like holograms, are not compatible with any symmetry; meaning such symmetry cannot be possible in quantum gravity.

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Gravity: We Might Have Been Getting It Wrong This Whole Time

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  • Einstein (Score:3, Interesting)

    by Njovich ( 553857 ) on Saturday January 25, 2020 @02:09AM (#59654492)

    I'm pretty sure that when Einstein got out of his time machine from the future and told us that gravity is the curvature of time and space, that he wasn't wrong. He didn't even realize what it meant himself, he must have just read that in future Wikipedia and forgot to bring along the details.

    • I'm pretty sure...

      Alrighty then.

    • I'm pretty sure that when Einstein got out of his time machine from the future and told us that gravity is the curvature of time and space, that he wasn't wrong.

      See? That's the thing. Gravity is NOT a fundamental force, it is the result of the bending of spacetime, it does not bend spacetime. What bends spacetime? Mass/Energy. Well, mass doesn't actually bend spacetime, spacetime is a field generated by massenergy.

      There is spacetime, electromagentism, and massenergy. Everything that physically exists comes from the interactions of those three 2axis "things".

      Gravity is not a fundamental force. It is the result of massenergy dictating to spacetime what it should look

  • by Kalendraf ( 830012 ) on Saturday January 25, 2020 @02:13AM (#59654494)
    Found the story here: https://phys.org/news/2020-01-... [phys.org]
  • Gravity is a lie,
    the earth sucks

    • by Mal-2 ( 675116 )

      The sun doesn't emit light, it sucks dark. That's also what keeps us in orbit.

    • by rtb61 ( 674572 )

      The earth displaces quantum space, as we do and hence we attract each other as we displace quantum space, the greater the density of the quantum particles we are made of, the greater the displacement of quantum space and the greater the attraction to other mass expressing particles. Probably a specific range of quantum particles, gravitons and the greater the mass expression high density quantum particle normal space constructs (us) the further and more strongly it propagates out into the graviton field, we

  • Meh (Score:5, Insightful)

    by jd ( 1658 ) <imipak@[ ]oo.com ['yah' in gap]> on Saturday January 25, 2020 @02:29AM (#59654506) Homepage Journal

    If unproven theory X is true and unproven implication y us true, then we can conclude z.

    Ok. That's valuable in understanding the consequences of ideas and how you can test theories by implication.

    It is not a proof of anything.

    We have no evidence for any of the components of the model, all we have now is a means to test those models (asymmetry) when the models cannot be examined directly.

    Nothing more.

    • Thanks for saying it. This kind of flawed logic seems to be gaining respectability somehow and it scares the hell out of me.

      • This is how science always worked, I think maybe people are just getting dumber and arrogant and questioning science more and more.
    • That's true. You can make as many cool models as you wish, but there's no guarantee that they'd actually map to universe's low level workings. There's just too many possibilities but not enough empirical data, that's the reason they grasp for symmetries to get at least something hopefully. But it's known fact that we get gravity wrong. No need for any more proofs of that. All attempts to combine quantum mechanics and gravity at low scales give nonsensical results. There are some approaches to build true qua
    • > It is not a proof of anything.

      Assuming their work is correct, a subset of current experimental models can be discarded.

      Since we won't have enough people working on models until a generation after we get everybody clean water, power, and sanitation, it's still valuable to narrow the problem domain.

  • I have to get up and go to work every morning.
  • Unproven Hypothesis (Score:4, Informative)

    by Roger W Moore ( 538166 ) on Saturday January 25, 2020 @03:32AM (#59654564) Journal

    The pair then showed how quantum error correcting codes, which explain how three-dimensional gravitational phenomena pop out from two dimensions, like holograms, are not compatible with any symmetry; meaning such symmetry cannot be possible in quantum gravity.

    No, it means that _IF_ their model is correct, symmetry is not part of the fundamental theory of quantum gravity. Currently, there is zero evidence to suggest this idea is correct. Hence, it is entirely possible that quantum gravity does follow symmetries and this theory is just another failed attempt at explaining quantum gravity.

    Theoretical physicists are always coming up with new, interesting models to solve problems in physics. However, until it is experimentally verified and shown to be an accurate model of nature you cannot use it to draw any conclusions about nature.

    • No, it means that _IF_ their model is correct, symmetry is not part of the fundamental theory of quantum gravity.

      Or, more concisely, it means that their model is incompatible with symmetry. :-)

      Thanks for making a point too easily lost in our world that is ever more clever than smart.

  • We should not forget, that such mental models, no matter how nice they may be, only ever become science, when they both give testable predictions, and those actually match observed reality!

    And mathmatical "proof" is useless, when it is built on axioms that aren't tested in reality. Otherwise it can at most become a religion, and not even a hypothesis.

    This here builds on so much stuff that is not yet even on that level of a proper hypothesis with predictions, that it might aswell be a game of Dungeons &

    • We should not forget, that such mental models, no matter how nice they may be, only ever become science, when they both give testable predictions, and those actually match observed reality!

      And mathmatical "proof" is useless, when it is built on axioms that aren't tested in reality. Otherwise it can at most become a religion, and not even a hypothesis.

      This here builds on so much stuff that is not yet even on that level of a proper hypothesis with predictions, that it might aswell be a game of Dungeons & Dragons, with how useless it is for predicting anything in reality.

      Like, maybe try to turn that holographic analogy into more than a hack, before building on it.
      Otherwise you end up like string "theory". ;)

      Preach it. String "theory" is actually string "hypothesis." It was developed as a way to avoid the "infinity problem" where general relativity equations resolve to zero in the denominator for very large values of gravity.

      While string does help there, it also calls for at least 11 dimensions and multiple universes.

      String predicts nothing and can't be tested. It's not a theory.

      However, this new paper is interesting because it provides food for thought. It would be a mistake to dismiss it.

      Einstein's epiphanies

  • So basically, nature does not abide our neat and tidy categorization of it. Long-standing issue in epistemology. Don't mistake the map for the territory.

  • Quantum gravity / supergravity / GUT, etc. has been the holy grail of physics for over a hundred years.
    We know a lot about gravity, and the one thing we've been absolutely sure of for a quite a while is that we've been getting it wrong.

  • I get gravity wrong every single time when I'm drunk like a skunk.

  • Alternate title: Gravity: Have We Been Getting It Wrong This Whole Time?

    Hirosi Ooguri: Constraints on Quantum Gravity 1 [youtu.be] — 28 May 2019

    One of the points of my lecture is question about whether the standard paradigm works in a case with gravity. In the particle physics literature there is the thing called Hinchliffe's Rule that says that when the title is in the form of a question then the answer is always "no". It should be obvious to you that if I ask this question that the answer should be "no".

    See al

  • Gravity may indeed disconnect at the microscopic. A similar thing happened with velocity.

    All these millennia, even going back to the days of cave persons throwing spears, we knew precisely how speed works. Then, in 1905 Einstein showed that "excessive" speed introduced weirdness. Novices often ask, "Why the hell didn't we see this coming?" The answer is that we had no way to achieve speeds that are great enough.

    So, at traditional velocity, we don't need special relativity to get things done. Plugging values

  • The flat earthers will be emboldened by this.....
  • https://www.khouse.tv/on-deman... [khouse.tv] OR
    https://www.youtube.com/playli... [youtube.com]
    Don't gimme no grief if you haven't invested at least a couple of hours seeing what he's got to say. Everyone interested in information technology should invest some time in Dr. Missler's observations and insights. JUST CHECK HIM OUT FIRST...!

    [Gen 1:1-13 KJV] 1 In the beginning God created the heaven and the earth. 2 And the earth was without form, and void; and darkness [was] upon the face of the deep. And the Spirit of God moved upon the

  • For obvious reasons most of us already are aware of, it is the norm that much of what we've been taught will be overturned and corrected. Over the past recent years, I've read any number of Math PhDs who idiotically claim we are all six degrees separated from one another. Beyond not comprehending Prof. Milgram's original study results, it is arithmetically impossible --- and most blatantly and obviously so!

No skis take rocks like rental skis!

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