I Spacetime as emergent quantum phenomenon

Published in the peer reviewed Journal of Applied Mathematics and Physics is the intriguing paper with the following abstract:

https://file.scirp.org/Html/11-1721242_88041.htm

"Entanglement and the tunnel effect phenomena have been repeatedly observed and are generically accepted under orthodox quantum mechanics formalism. However, they remain rather inexplicable in the context of spacetime usual conceptualization. In the present work, we suggest an alternative quantum mechanics formalism, refining the pilot-wave theory initially proposed by de Broglie. We suggest that spacetime is an emergent phenomenon from a prior subquantum medium and that entanglement and the tunnel effect can be explained in terms of a nonlinear relation between space and time that is imposed by subquantum waves."

intro version: https://www.sciencealert.com/a-wild-new-papers-suggests-space-time-is-just-a-product-of-quantum-mechanics?fbclid=IwAR3tchJV-7y2997viGz-l5QiHqEXW3HIGPYY-pMVB34HUKyVR59jKLm7W2E

Pilot wave models (like Bohmian mechanics) have difficulty with relativistic quantum field theory. How would concept of subquantum waves aim to solve it?

The idea seems very basic. Can anyone kindly share what arxiv authors have proposed similar themes and what problems were encountered along the way?

Any help would be much appreciated! Thank you!
 

Ken G

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The core idea that spacetime emerges from quantum mechanics is sometimes expressed in the cryptic equation ER = EPR. This is a reference to two papers that involved Einstein and Rosen in 1935, one on the Einstein-Rosen bridge solution in GR that connects black holes to white holes, and the other is the famous Einstein-Podolsky-Rosen paradox about quantum entanglement. Einstein and Rosen likely had no idea these two papers shared any connections whatsoever, but there is a modern idea that spacetime's geometrical structure might somehow be enforced by hidden entanglements involving matter. Spacetime is then serving as a kind of mediator of quantum phenomena involving matter, but somehow we can use the concepts of space and time to gain intuitive access to essentially much more inscrutable entanglements. I don't know much more about it, but it would certainly be ironic if future physicists looked at our current frustrations with trying to unify quantum mechanics and gravity as the door that opened a much deeper insight into the nature of things.
 
The reference gave these words:

"In our proposal, space-time does not pre-exist, it is the result of a physical process by which the subquantum medium goes from a chaotic state to a more organised one."

This subquantum medium is something that Castro describes as "a kind of primordial foam from where space-time itself emerges".

You could think of it like a quantum miso soup: initially it's all stirred up, and nothing can be distinguished from the chaos. But as the soup settles and becomes more 'organised', structures begin to emerge.

"In fact, in our theory, these organised states correspond to subquantum waves, imposing how space and time behaves, giving rise to extreme cases, like the ones in entanglement and the tunnel effect," says Castro.

"As space-time different behaviours are, of course, signatures of gravity, you can now say that gravity is quantum."

For now this is all purely theoretical, but the researchers are working on ways to test their ideas.

One idea they have in mind involves the strange 'quantified' pattern seen in the placement of planets in our Solar System, which the researchers previously suggested hinted at the existence of stationary subquantum waves around our Sun."

https://www.sciencealert.com/mind-bending-new-theory-of-everything-suggests-there-s-a-hidden-force-that-controls-our-universe

Do you have objections, counterarguments to it or is it one of the hottest ideas ever proposed that can be key to the holy grail of quantum gravity?
 

Ken G

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I haven't read the article but a lot of the things they say sound pretty hokey to me. My uninformed guess is that this article is based around the important idea that spacetime is a kind of emergent order out of quantum chaos, but that idea doesn't come from them, and they don't seem to actually make any progress around the idea that isn't essentially "mumbo jumbo." But I could be wrong, that's just coming from the red flags I see waving. For example, there is a theory of quantum fields, but there is no theory of "subquantum" fields, so that sounds like mumbo jumbo. And the idea that the orbits of the planets show some residual of these subquantum effects seems too farfetched to even entertain seriously. But I don't know that there is nothing interesting there.
 
I haven't read the article but a lot of the things they say sound pretty hokey to me. My uninformed guess is that this article is based around the important idea that spacetime is a kind of emergent order out of quantum chaos, but that idea doesn't come from them, and they don't seem to actually make any progress around the idea that isn't essentially "mumbo jumbo." But I could be wrong, that's just coming from the red flags I see waving. For example, there is a theory of quantum fields, but there is no theory of "subquantum" fields, so that sounds like mumbo jumbo. And the idea that the orbits of the planets show some residual of these subquantum effects seems too farfetched to even entertain seriously. But I don't know that there is nothing interesting there.
This is the complete paper (with equations) published in the peer reviewed Journal of Applied Mathematics and Physics

https://file.scirp.org/Html/11-1721242_88041.htm

Try to browse it and kindly let me know what you think. It may be the biggest idea since Einstein or Bohr.
 

Ken G

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Difficulties with the font make the equations essentially impossible to read, unfortunately, so I can't really judge. The paper seems to replace standard quantum mechanics of waves with a "master equation" applying to wavelets, and makes some claims about how this is a useful thing to do, but as far as I could get before giving up on the equations, I did not find myself convinced. The whole business seems to rest on a 2003 paper by one of the authors, Croca, and if this paper really had the significance it claims, surely it would have made more of a splash in 15 years than it has. Still, I regard my critique as uninformed, and Croca might find it frustrating to be dismissed on such incidental grounds. If the paper is passing referees it should not be garbage, so there may well be something to it, but I have to decide what is worth the effort invested in trying to decide whether or not this nonlinear wavelet approach to quantum mechanics is really all it's cracked up to be-- and that's even before getting to entanglement or tunneling.
 

Fra

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While I definitely think that space (not sure about time) is an emergent in some way (to use the buzzword), but I am doubtful about the ideas in that paper.

"emergent phenomena, through subquantum waves, from the a priori basic physical reality identified with the subquantum medium."

I think this idea is far too simple, and also quickyl skimming the papers the mathematical ideas also seem simple. For me the first impression does not tell me its something worth spending more time on. I think the WAY its emergent, needs to be understood not from a classical self-organisation in a given "medium", but in a way where the medium and the structure evolves together; and to make sense to this circular reference deeper ideas are IMO needed that i can hint from that paper?

/Fredrik
 
While I definitely think that space (not sure about time) is an emergent in some way (to use the buzzword), but I am doubtful about the ideas in that paper.

"emergent phenomena, through subquantum waves, from the a priori basic physical reality identified with the subquantum medium."

I think this idea is far too simple, and also quickyl skimming the papers the mathematical ideas also seem simple. For me the first impression does not tell me its something worth spending more time on. I think the WAY its emergent, needs to be understood not from a classical self-organisation in a given "medium", but in a way where the medium and the structure evolves together; and to make sense to this circular reference deeper ideas are IMO needed that i can hint from that paper?

/Fredrik
But is it not the "in" thing now that Lorentz invariance is not fundamental and the basic entities don't obey Lorentz invariance?

Also in Demystifier paper http://de.arxiv.org/pdf/1811.11643v2 (which I browsed days ago in the archive). It's compatible with the idea that the particles in BM are about subquantum waves/particles, quoting it:

"5 Beyond relativistic QFT

5.1 What particles is BM about?

So far we were talking about particle trajectories, but we did not specify what kind of particles we are talking about. Is it atoms? Or is it smaller particles such as protons and neutrons? Or is it more fundamental particles like electrons, quarks, photons and Higgs? Or perhaps quasiparticles (collective excitations), like phonons? As we stressed several times, the predictions on perceptibles do not depend much on those details. Yet the details are important for their own sake.

Take for example a phonon. The phonon trajectory is certainly not a beable because
we know that one phonon is a collective motion of many atoms. Photons and electrons, on the other hand, are usually viewed as fundamental particles, rather than quasiparticles. But do we actually know that photon or electron is not a collective excitation of some more fundamental degrees of freedom? We stress that we do not know that.

Let us explain. Theories which serve as good approximations at longer distances, but not at smaller distances, are called effective theories [13]. The theory of phonons is certainly an effective theory. There is some evidence that the Standard Model of “elementary particles” is an effective theory too [12, 13]. It is not known what the fundamental theory behind the Standard Model is, but one viable possibility is that the “elementary particles” like electrons, quarks, photons, etc. are in fact collective excitations. Collective excitations of what? Of some truly elementary particles. What those truly elementary particles are? We do not know, because we still do not have the theory of everything. We can only say that this hypothetic truly elementary particles are for photons (and other Standard Model “elementary particles”) what the atoms are for phonons.

How is that relevant to BM? The point is that Bohmian particle trajectories can only be beables for the truly elementary particles, whatever those truly elementary particles are. (For an illustration of that idea see also Sec. 5.4.) Hence it seems very likely that BM trajectories are not beables for the Standard Model “elementary particles” like electrons, quarks, photons and Higgs."

Demystifier view is that Einstein relativity (both special and general) is emergent. So they are similar in ideas.

If Croca stuff is incorrect. Demystifier ideas also incorrect? How do the two ideas differ if you see the subtle distinctions?
 

Doc Al

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Thread closed for moderation
 

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