A Volovik vs Witten vs Wen, etc.

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Demystifier

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What are framework besides condensed matter framework where it can be true?
Any Lorentz-violating theory with higher derivatives in the effective action.
 
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1. can be true even without the condensed matter framework.

If QM is fundamental (which in my approach I assume it is), then De Broglie wavelength and HUP are fundamental.
What models have you encountered where there is another layer below QM where deBroglie wavelength and HUP don't apply anymore?
 

Demystifier

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What models have you encountered where there is another layer below QM where deBroglie wavelength and HUP don't apply anymore?
The 't Hooft's theory of local superdeterministic hidden variables.
 
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The 't Hooft's theory of local superdeterministic hidden variables.
I was googling about this and encountered this for instance https://arxiv.org/abs/1105.4326

But it still used QM with HUP. Why doesn't
local superdeterministic hidden variables require HUP? It has no wave function anymore? What take its place?
 

Demystifier

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Yes, in the 't Hooft's theory there is no wave function. The fundamental thing there is the cellular automaton. For a review see http://de.arxiv.org/abs/1405.1548
It is dense reading. So the cellular automaton QM theory can describe strings in the planck scale that doesn't necessarily involve huge energy, and turtles (representing complex objects) can even occur inside the planck scale?

But I haven't heard of the cellular automaton much. Why don't you like it?
 

Demystifier

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Why don't you like it?
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.
 
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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.
Can't you have HUP without superdeterminism? HUP is simply when x is so small, momentum is so large. So in the planck scale where x is so tiny, momentum or energy so big. What is the relationship of superdeterminism and HUP?

Also does having wavefunction already implied correlations? correlations in what manner?

Are there other interpretative formalisms without superdeterminism that has no HUP too? Yes, we can discount superdeterminism as it is so unlikely, almost just a planck change of being true.
 
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E=p^2/2m is the free non-relativistic dispersion relation. For a non-free case, non-relativistic dispersion can be different.
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?
 

Demystifier

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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
$$H=\frac{p^2}{2m}$$
 
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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

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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.
 
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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:
"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 }
{\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}
{\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}
{\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

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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.
 
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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?
 
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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

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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).
 
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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.
 
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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?
 
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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

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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.
 
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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

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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.
 
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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)?
 

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