Volovik vs Witten vs Wen, etc.

[Demystifier]

By the way, what does "free" mean above? Do you have references for this free vs non-free case?

I thought "free" meant condense matter stuff was involved. But even without it, Lorentz invariance could still be violated at small scale. So what does "free" exactly man?

Free means that the Hamiltonian is just
$$H=\frac{p^2}{2m}$$

 

[lucas_]

Perhaps, but I am not aware of any.

Hold on.
If very small scale had no Lorentz invariance and further acceleration of the particle by an accelerator stronger than LHC might result in a
decrease of its energy: meaning momentum and energy got decoupled. Couldn't this affect HUP too? HUP says that when x is very small, momentum is large and energy is large. But if momentum and energy got decoupled without lorentz invariance at small scale. Couldn't this make for example preons inside quark (or stuff inside Planck scale) have very much less energy?

 

[Demystifier]

HUP says that when x is very small, momentum is large and energy is large.

No, HUP says that when uncertainty of x is very small, then the uncertainty of momentum is very large. It says nothing about energy.

 

[lucas_]

No, HUP says that when uncertainty of x is very small, then the uncertainty of momentum is very large. It says nothing about energy.

I think you have heard about the mass paradox in preons, quoting:
https://en.wikipedia.org/wiki/Preon"The mass paradox[edit]

One preon model started as an internal paper at the Collider Detector at Fermilab (CDF) around 1994. The paper was written after an unexpected and inexplicable excess of jets with energies above 200 GeV were detected in the 1992–1993 running period. However, scattering experiments have shown that quarks and leptons are "pointlike" down to distance scales of less than 10−18 m (or 1⁄1000 of a proton diameter). The momentum uncertainty of a preon (of whatever mass) confined to a box of this size is about 200 GeV/c, 50,000 times larger than the rest mass of an up-quark and 400,000 times larger than the rest mass of an electron.

Heisenberg's uncertainty principle states that Δ ⁡ x ⋅ Δ ⁡ p ≥ 1 2 ℏ {\displaystyle \operatorname {\Delta } x\cdot \operatorname {\Delta } p\geq {\tfrac {1}{2}}\hbar }

and thus anything confined to a box smaller than Δ ⁡ x {\displaystyle \operatorname {\Delta } x}

would have a momentum uncertainty proportionally greater. Thus, the preon model proposed particles smaller than the elementary particles they make up, since the momentum uncertainty Δ ⁡ p {\displaystyle \operatorname {\Delta } p}

should be greater than the particles themselves.

So the preon model represents a mass paradox: How could quarks or electrons be made of smaller particles that would have many orders of magnitude greater mass-energies arising from their enormous momenta? This paradox is resolved by postulating a large binding force between preons cancelling their mass-energies.[citation needed] "

So high momentum has high energy as in "The momentum uncertainty of a preon (of whatever mass) confined to a box of this size is about 200 GeV/c, 50,000 times larger than the rest mass of an up-quark and 400,000 times larger than the rest mass of an electron."

So HUP has to do with high energy. Why don't you believe it?

 

[Demystifier]

So HUP has to do with high energy. Why don't you believe it?

In the preon model they assumed that relativity is valid at the level of preons. But that assumption does not necessarily need to be taken for granted in other models.

 

[lucas_]

In the preon model they assumed that relativity is valid at the level of preons. But that assumption does not necessarily need to be taken for granted in other models.

Yes. That's why I said that in condense matter model where Lorentz invariance didn't hold in small scale. HUP having large momentum and energy won't hold too and this means small scale could have many particles like preons with much less mass?

 

[lucas_]

In the preon model they assumed that relativity is valid at the level of preons. But that assumption does not necessarily need to be taken for granted in other models.

This is very important. If relativity was not valid at small scale where preons existed, then it didn't have to have 200 GeV?

This is my justification to vote for 100 TeV (and beyond) particle accelarators to see if relativity was valid at very small scale. And strong counterarguments to Hossenfelder taking negative stand against newer particle accelarators. So kindly emphasize if HUP and particles that supposedly require higher energy particles didn't have to exist if relativity not there at very small scale. Thank you!

 

[Demystifier]

This is very important. If relativity was not valid at small scale where preons existed, then it didn't have to have 200 GeV?

Yes.

This is my justification to vote for 100 TeV (and beyond) particle accelarators to see if relativity was valid at very small scale. And strong counterarguments to Hossenfelder taking negative stand against newer particle accelarators. So kindly emphasize if HUP and particles that supposedly require higher energy particles didn't have to exist if relativity not there at very small scale. Thank you!

This will not change the Hossenfelder's opinion, because she will tell that we do not have a strong reason to think that relativity is violated at 100 TeV (and beyond).

 

[lucas_]

Yes.This will not change the Hossenfelder's opinion, because she will tell that we do not have a strong reason to think that relativity is violated at 100 TeV (and beyond).

Ok. Back to phonons and fundamental particles. Since the wave function underlying the fundamental particles are what causes the interaction in the atoms, then a helium or oxygen atom in the fundamental particle version would still look like helium or oxygen atoms? Only with trajectories?

Can't you make a version where the quasiparticles like electrons, quarks are still described by the wave function, only there is another layer deeper where there are trajectories yet not describable by any wave function, like a turtle or strings that don't look like the helium or oxygen?

Kindly elaborate on the two cases above so we become more familiar to the distinctions.

 

[lucas_]

Ok. Back to phonons and fundamental particles. Since the wave function underlying the fundamental particles are what causes the interaction in the atoms, then a helium or oxygen atom in the fundamental particle version would still look like helium or oxygen atoms? Only with trajectories?

Can't you make a version where the quasiparticles like electrons, quarks are still described by the wave function, only there is another layer deeper where there are trajectories yet not describable by any wave function, like a turtle or strings that don't look like the helium or oxygen?

Kindly elaborate on the two cases above so we become more familiar to the distinctions.

In essence. I don't want the fundamental particles to look like helium, oxygen or flowers. They really look natural objects like flowers? (Kindly confirm). But when we look at flowers. We are looking at the quasiparticles and not the fundamental particles. Do they look the same? I want another layer. So is the following possible?

strings -> fundamental particles with beables (no Lorentz invariance) -> quasiparticles like electrons, photons

or better yet, since strings have Lorentz invariance built in, then something like

Newton -> fundamental particles with beables (no Lorentz invariance) -> quasiparticles like electrons, photons?

But Newton shouldn't able to produce wave function. Or can it? What non-relativistic thing can create the initial wave function?

 

[lucas_]

In essence. I don't want the fundamental particles to look like helium, oxygen or flowers. They really look natural objects like flowers? (Kindly confirm). But when we look at flowers. We are looking at the quasiparticles and not the fundamental particles. Do they look the same? I want another layer. So is the following possible?

strings -> fundamental particles with beables (no Lorentz invariance) -> quasiparticles like electrons, photons

or better yet, since strings have Lorentz invariance built in, then something like

Newton -> fundamental particles with beables (no Lorentz invariance) -> quasiparticles like electrons, photons?

But Newton shouldn't able to produce wave function. Or can it? What non-relativistic thing can create the initial wave function?

Demystifier. There seems to be some conflicts in the model. Reviewing your paper in page 13 "The phonon trajectory is certainly not a beable because we know that one phonon is a collective motion of many atoms".

That is. A phonon is a collective motion of many atoms.

Later you wrote "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".

But these collective excitations can't be described by wave functions. Because if they do, they would mess up the behavior of atoms which only works in the case of hydrogen for example where we have one proton and one electron. Not a collective excitations of many nucleus and electrons. This would mess up the spectrum. So how can you still use the concept of wave functions for these collective excitations of many fundamental particles? As you said yourself that "one phonon is a collective motion of many atoms".

Unless you mean the interactions between atoms and matter is the way the phonons behave, or is it when the fundamental particles behave?

 

[Demystifier]

But these collective excitations can't be described by wave functions. Because if they do, they would mess up the behavior of atoms

That's not true. See Eqs. (32) and (34) in my paper. Eq. (32) describes a collective excitations of atoms, Eq. (34) describes a wave function of a single phonon, and yet those two wave functions represent the same physical state.

 

[lucas_]

That's not true. See Eqs. (32) and (34) in my paper. Eq. (32) describes a collective excitations of atoms, Eq. (34) describes a wave function of a single phonon, and yet those two wave functions represent the same physical state.

Ok.

By the way. Volovik didn't use the concept of beables in the fundamental particles. In condense matter physics, you need nucleus and atoms to have phonons. So how did Volovik able to produce phonons without any beables in the fundamental subquantum realm? In condense matter analogy. How can you produce phonons without any atoms?

 

[Demystifier]

You need atoms for phonons, but it's not necessary to say that atom is a beable. The concept of beable is needed if you insist on saying that something (atom, phonon, or whatever) exists even when it is not observed. If you (or Volovik) only care about observations, then you don't need beables.

 

[lucas_]

You need atoms for phonons, but it's not necessary to say that atom is a beable. The concept of beable is needed if you insist on saying that something (atom, phonon, or whatever) exists even when it is not observed. If you (or Volovik) only care about observations, then you don't need beables.

Ok. Let's not use the word beables then. I just want to know what is volovik version of atoms to produce the phonons in his subquantum realm (where QM is more fundamental than QFT)?

 

[Demystifier]

Why don't you take a look at his book or some of his papers?

 

[lucas_]

Why don't you take a look at his book or some of his papers?

Ok. Will try to read them again. I mostly read discouraging comments about Volovik and maybe many physicists avoid it. So I don't continue after a dozen pages. I tend to avoid nonpromising approach like Gerard 'thooft superdeterministic Cellular Automaton theory of QM. etc.

"I believe Wen would like emergent fermions, while Volovik wouldn't mind fundamental fermions. Neither is promising, though both are inspiring and worth studying. I think AdS/CFT is a working example for emergent gravity in some universes (not ours) that is very much in the spirit of condensed matter. So we have examples of emergent gravity (AdS/CFT) and emergent QED and QCD (Levin and Wen), but no examples of emergent chiral fermions (yet?)."

Reference: https://www.physicsforums.com/threads/what-are-the-differences-between-volovik-wen-theories.348431/

 

[lucas_]

Why don't you take a look at his book or some of his papers?

I recalled now. I actually had Volovok book "The Universe in a Helium Droplet".
James Bjorken wrote the preface which discouraged me:

"It is often said that the problem of the very small cosmological constant is
the greatest mystery in cosmology and in particle physics, and that no one has
any good ideas on how to solve it. The contents of this book make a lie of that
statement. The material in this monograph builds upon a candidate solution to
the problem, often dubbed `emergence'. It is a solution so simple and direct that it can be stated here in this foreword. Visualize the vacuum of particle physics as if it were a cold quantum liquid in equilibrium. Then its pressure must vanish, unless it is a droplet - in which case there will be surface corrections scaling as an inverse power of the droplet size. But vacuum dark pressure scales with the vacuum dark energy, and thus is measured by the cosmological constant, which indeed scales as the inverse square of the `size' of the universe. The problem is
`solved'.

But there is some bad news with the good. Photons, gravitons, and gluons
must be viewed as collective excitations of the purported liquid, with dispersion
laws which at high energies are not expected to be relativistic. The equivalence
principle and gauge invariance are probably inexact. Many other such ramications exist, as described in this book. And experimental constraints on such deviant behavior are extremely strong. Nevertheless, it is in my opinion not out of the question that the diffulties can eventually be overcome. If they are, it will mean that many sacrosanct beliefs held by almost all contemporary theoretical particle physicists and cosmologists will at the least be severely challenged.

This book summarizes the pioneering research of its author, Grisha Volovik,
and provides a splendid guide into this mostly unexplored wilderness of emergent particle physics and cosmology. So far it is not respectable territory, so there is danger to the young researcher venturing within - working on it may be detrimental to a successful career track. But together with the danger will be high adventure and, if the ideas turn out to be correct, great rewards. I salute here those who take the chance and embark upon the adventure. At the very least they will be rewarded by acquiring a deep understanding of much of the lore of condensed matter physics. And, with some luck, they will also be rewarded by uncovering a radically di®erent interpretation of the profound problems involving the structure of the very large and of the very small.
Stanford Linear Accelerator Center James D. Bjorken
August 2002"

First he said "The material in this monograph builds upon a candidate solution to
the problem, often dubbed `emergence'. It is a solution so simple and direct that
it can be stated here in this foreword. Visualize the vacuum of particle physics as if it were a cold quantum liquid in equilibrium...".

We know our vacuum is not a cold quantum liquid in equilibrium, is it? So what's the point of writing about something that didn't exist. This was the reason I asked what really was Volovik version of the atoms in the vacuum where our particles were the phonons. It couldn't really be cold quantum liquid, is it?

Second, he wrote "So far it is not respectable territory, so there is danger to the young researcher venturing within.."

So James Bjorken already gave such a negative tone in the first page. Also he made it sound like it was only to solve the cosmological constant problem.

Has anyone read the book besides Demystifier? What are others views of it? It will take me 2 years to read it. Is the "cold quantum liquid" supposed to be literal? Has it not been falsified already? Does this fall under the subject of Subquantum Physics?

 

[Demystifier]

We know our vacuum is not a cold quantum liquid in equilibrium, is it?

Why do you think so? We do not know whether it is true or not at the fundamental level. Of course, it is not so according to our Standard Model description, but the idea is precisely that the Standard Model description is just an effective theory not valid at the fundamental level.

Second, he wrote "So far it is not respectable territory, so there is danger to the young researcher venturing within.."

That is true, but your own ideas about certain things ( ) are even less respectable territory, so you are the last person for whom I expect to be discouraged by not being in a respectable territory.

 

[lucas_]

Why do you think so? We do not know whether it is true or not at the fundamental level. Of course, it is not so according to our Standard Model description, but the idea is precisely that the Standard Model description is just an effective theory not valid at the fundamental level.

So it's not yet refuted. Ok. I'll read the whole book then. I thought our vacuum was not shown to be a cold quantum liquid already because when you talk to relativity people. They would tell your the entire quantum vacuum is Lorentz invariance and not a medium or with turtles. So it may turtles all the way.

That is true, but your own ideas about certain things ( ) are even less respectable territory, so you are the last person for whom I expect to be discouraged by not being in a respectable territory.

The quote was just shown that it was not popular. So I thought some parts were refuted already. String theory was really still in infancy so many ideas still possible (but LHC already constrained so many).

 

[lucas_]

About this whole idea of Lorentz invariance thing or relativity being emergent. I'd like to hear ideas from researchers in computer simulations who also need to use Lorentz invariance in the simulation or world building. Without such preference. The simulation occupants can learn of the limitations in the program? I hope the Universe as Simulation researchers (followers of Tegmark for example) or proponents can comment a thing or two about the advantage (if any) the need of Lorentz invariance in the program.

 

[Demystifier]

I thought our vacuum was not shown to be a cold quantum liquid already because when you talk to relativity people. They would tell your the entire quantum vacuum is Lorentz invariance and not a medium or with turtles.

They confuse the map (Standard Model) with the territory.

 

[lucas_]

They confuse the map (Standard Model) with the territory.

If there would be evidence for it (of course I have to look for evidence), what is the best catchy term for the new physics if it would be valid (or even to refer to the subfield for discussions with physicists).. is it...

1. Subquantum physics? (does "subquantum" makes sense?)
2. Super Quantum Physics (Super since it's fundamental?)
3. Sub-vacuum physics?
4. Super-vacuum physics?
5. De-Renormalization Group Physics?
6. Neo-Ether Theory (Do all physicists understood neo-ether mean something not related or have already encompassed the result of the Michelson-Morley experiment?)
7. Witten-Ether theory (since Witten is the leader of all physicists?)
8. Vacuum Engineering physics
9. Non-Gauge, Non-Lorentzian Scalar Physics?
10. Can you recommend any good catchy term to refer to the concept? Anyone else?

 

[Demystifier]

Among the offered options, I think 6. describes it the best. But unfortunately the notion of "ether" is often associated with crackpottery, so if you want to avoid such a negative connotation, you can use a more straight notion, perhaps effective theory physics or emergent physics, suggesting that the theories that we currently know are effective theories that emerge from as yet unknown more fundamental physics.

 

[lucas_]

Among the offered options, I think 6. describes it the best. But unfortunately the notion of "ether" is often associated with crackpottery, so if you want to avoid such a negative connotation, you can use a more straight notion, perhaps effective theory physics or emergent physics, suggesting that the theories that we currently know are effective theories that emerge from as yet unknown more fundamental physics.

What is more believable in the current Ph.D theoretical physics community: the effective field theory where lorentz invariance, etc is emergent or the concept of Shadow matter in E8xE8' heterotic superstring theory?

In present belief about E8xE8' heterotic superstring theory. Only gravity acts between superstrings of ordinary matter and shadow matter due to the simplistic unproven assumption that the former are singlet representations of E8' and that the latter are singlet representations of E8, so that the non-abelian gauge fields acting on one type do not act on the other type.

The consequence is that none of the 496 gauge fields of E8xE8' can cross the gap between the two 10-dimensional branes predicted by this type of heterotic superstring theory.

But note heterotic superstring theory is not M-theory but only but one of its approximations. What if other fields existing in the 15 higher dimensions outside these branes play no part in the interactions between superstrings. What if these other fields can couple superstrings of shadow and ordinary matter, both of which extend in this higher-dimensional space beyond 11-dimensional supergravity space-time. Is this still possible? They can maintain global cohesion between the shadow matter and physical matter.

If we will let physicists vote. Would they choose the above possibility of E8xE8' shadow matter (with possible global cohesion with normal matter) or effective field theory where lorentz invariance is just the emergent (whereas E8xE8' has fundamental lorentz invariance)?

 

[Fractal matter]

Lets suppose Volovik and Wen are right. Can their many-body systems be approximations of a more fundumental QFT ?

 

[Demystifier]

Lets suppose Volovik and Wen are right. Can their many-body systems be approximations of a more fundumental QFT ?

In principle, yes. In principle, we could even have an infinite regress: many-body system emerging from a QFT, which emerges from a many-body system, which emerges from QFT, which ...

 

[Fractal matter]

In principle, yes. In principle, we could even have an infinite regress: many-body system emerging from a QFT, which emerges from a many-body system, which emerges from QFT, which ...

As i understand it, the critical speed in that more fundamental QFT will be even faster and one gets usual criticism.

I wonder if QM and QFT may correspond to particular scales(approximations) of deterministic dynamic fractal system. I have a sense it does. For example in renormalization group Schröder's equation is used, which is said to be suitable to encoding self-similarity. Quote from wikipedia: "Iterated functions are objects of study in ... fractals, dynamical systems ... and renormalization group physics."

Giulio Prisco shares the view to some extent: https://turingchurch.net/down-in-the-fractal-depths-of-quantum-matter-and-space-time-fe0c83b3516

I'd like to know if Ervin Goldfain and Gianluca Calcagni pursue the same idea.

https://www.academia.edu/22396275/R...ndom_fractal_topology_in_quantum_field_theory

https://www.researchgate.net/publication/230802696_Introduction_to_Multifractional_Spacetimes
https://www.researchgate.net/publication/301842283_Lorentz_violations_in_multifractal_spacetimes

 

[Demystifier]

As i understand it, the critical speed in that more fundamental QFT will be even faster and one gets usual criticism.

If more fundamental QFT is not relativistic, i.e. if its action is not Lorentz invariant, then there does need to be a critical speed at all.

 

[Fractal matter]

If more fundamental QFT is not relativistic, i.e. if its action is not Lorentz invariant, then there does need to be a critical speed at all.

For observers restricted to using sound clocks and rods the action will be Lorentz-invariant(arXiv:1612.06870v2). So it seems the symmetries of the action describe the qualities of the observer.

we could even have an infinite regress: many-body system emerging from a QFT, which emerges from a many-body system, which emerges from QFT, which ...

I cherish this view on qm together with superdeterminism. Also Wolfram's rewriting rules are interesting in this context. Is this a bunch of effective qft's(and corresponding observers of different types) each possessing its own symmetries? Or is the word effective inappropriate, because there are different qft's/spacetimes involved? Can this be considered as a single qft? What's different, it seems, are types of observers.

 

[Giulio Prisco]

Is it Volovik using quantum mechanics as more fundamental to QFT?

At the very end of his book Volovik says that (something like) QFT can be derived from his superfluid vacuum theory but QM is still fundamental, so yes. He also says that further research could also explain the origin of QM: “However, in exploring the quantum liquids with Fermi points, we are probably on the right track toward understanding the properties of the quantum vacuum and the origin of quantum mechanics.”

Besides that, I’m resurrecting this thread to ask this: I have the impression that something analogous to string theory could be also derived in Volovik’s approach. OK different number of dimensions but perhaps the superfluid vacuum could be described by a QFT with a string dual? Now this would be an intriguing unification! Any pointers?

Edited: this seems a good pointer:
https://www.nature.com/articles/478302a

And a book:
https://www.amazon.com/dp/1107080088/?tag=pfamazon01-20

Will post others.

 

[Giulio Prisco]

Essentially, because I don't like superdeterminism. Superdeterminism says that correlations are not due to laws of physics, but are contingent properties of special initial conditions. In this way, superdeterminism can nominally explain anything but actually explains nothing.

If Nicolas Gisin is right then superdeterminism is trivially true BUT the world is NON-deterministic!

https://www.quantamagazine.org/does...from-a-century-old-approach-to-math-20200407/

 

[Giulio Prisco]

Among the offered options, I think 6. describes it the best. But unfortunately the notion of "ether" is often associated with crackpottery, so if you want to avoid such a negative connotation, you can use a more straight notion, perhaps effective theory physics or emergent physics, suggesting that the theories that we currently know are effective theories that emerge from as yet unknown more fundamental physics.

Superfluid vacuum physics seems good to me.

 

[MathematicalPhysicist]

If Nicolas Gisin is right then superdeterminism is trivially true BUT the world is NON-deterministic!

https://www.quantamagazine.org/does...from-a-century-old-approach-to-math-20200407/

The laws of physics imply that the passage of time is an illusion.

No need to read any further, "time is an illusion".
If the laws of physics imply that, would you like to change them?
I asked if the poster Creator still posts in PF once, but it seems he had stopped posting.
We can ask him/her...

 

[Giulio Prisco]

No need to read any further, "time is an illusion".
If the laws of physics imply that, would you like to change them?
I asked if the poster Creator still posts in PF once, but it seems he had stopped posting.
We can ask him/her...

The quotes are formatted in a way that gives the impression that I said "The laws of physics imply that the passage of time is an illusion," but I didn't say and don't think that!