Ali and Das, "Cosmology from quantum potential"

[write4u]

I don't think so. Gravity (GR) does influence quantum events. See e.g.
http://www.ift.uam.es/oldIFT/paginaspersonales/bellido/cuantica/articulos/PhysRevLett.34.1472.pdf

Thank you for responding to my question.

As layman , much of the language was beyond my knowledge, but I did get the impression that gravity can and does affect the wavelength of the particle, but I am not sure if it answered the question of affecting the quantum function itself.

I realize that gravity experiments on light revealed that gravity can alter the path of photons or even shift its wavelength. However, I do not recall reading that gravity also affects the speed of photons themselves. If that were the case, how could SOL (IMO, the ultimate speed at which quantum is able to function) be a constant?

The problem I have is the question if QM precedes GR. Kinda like the chicken and the egg question. If quantum is responsible in the formation of massive gravitational objects which then exert influence on the behavior of particles, do we not have a dependency problem? Gravity depends on mass, mass depends on QM. This seems to indicate that GR emerges from QM.

Is there an answer to that question as well, or did I miss it in the link you provided? Again, thanks for indulging my ignorance. It's a fascinating subject.

 

[Demystifier]

However, I do not recall reading that gravity also affects the speed of photons themselves. If that were the case, how could SOL (IMO, the ultimate speed at which quantum is able to function) be a constant?

Well, you can say that it is gravity which determines that the speed of light is a constant. Namely, the constant speed of light is a consequence of the fact that the spacetime metric is locally Minkowski, but it is gravity which determines the local properties of the metric.

 

[write4u]

Well, you can say that it is gravity which determines that the speed of light is a constant. Namely, the constant speed of light is a consequence of the fact that the spacetime metric is locally Minkowski, but it is gravity which determines the local properties of the metric.

Thank you , I'll do some further research on this as it is clear I do not have sufficient information to even make intuitive statements.

 

[wabbit]

The problem I have is the question if QM precedes GR. Kinda like the chicken and the egg question. If quantum is responsible in the formation of massive gravitational objects which then exert influence on the behavior of particles, do we not have a dependency problem?

Indeed. Neither precedes the other. Quantum Gravity is formulated as fitting GR into QM but it's not a one-way street, what should emerge is a unified theory including both. Some very interesting consideration about that feedback from Gravity to QM are found in Gambini & Pulin, The Montevideo Interpretation of Quantum Mechanics: a short review and from a more philosophical perspective Gambini, Lewowicz, Pulin ; Quantum mechanics, strong emergence and ontological non-reducibility

 

[write4u]

Well, you can say that it is gravity which determines that the speed of light is a constant. Namely, the constant speed of light is a consequence of the fact that the spacetime metric is locally Minkowski, but it is gravity which determines the local properties of the metric.

As layman, I have a problem with categorizing the functions of QM and GR. Intuitively I view QM as an independent function in the creation of physical objects, whereas GR is a secondary phenomenon, which describes the relationship of physical objects. As to gravity, I see that more as trajectory shaping force, but not causal to the quantum function in and of itself.

I am completely open to correction on these simple propositions. The maths are beyond my knowledge, but I question the necessity of mathematical explanations as it relates to my fundamental question if QM is a fundamental function, independent of any and all external forces except energy.

 

[BiGyElLoWhAt]

Hopefully this isn't too far off topic. Stumbling on to this led me down a trail of bread crumbs which i feel ultimately aided my "understahding" (hah!) of GR. Try googling kaluza-klein and also william k clifford. I actually might start a new thread about this, because it raises some interesting questions for me.

 

[wabbit]

As layman, I have a problem with categorizing the functions of QM and GR. Intuitively I view QM as an independent function in the creation of physical objects, whereas GR is a secondary phenomenon, which describes the relationship of physical objects. As to gravity, I see that more as trajectory shaping force, but not causal to the quantum function in and of itself.

As another layman, please take what I say for what it is - the musings of a fellow amateur, nothing more. But, hoping this doesn't stray too far into the speculative (to be clear it is in no way original, just a rehashing/distortion of pickings from what some actual physicists have said) - here's my tentative view of the articulation of QM and GR:

- A generalized/expanded form of QM that accounts for GR would indeed (should it be established) be the more general theory as it describes "all" aspects of measurements/interactions/observations including their spatial/time properties.

- Current QM incorporates (in QFT) SR as its theory of spacetime, but not yet GR so it does not encompass GR at all and isn't even strictly speaking compatible with it. (*)

- GR as the theory of spacetime relations, will be one aspect of the full QM ; but only after it is itself included in a more general theory of Quantum Gravity, where spacetime itself is fundamentally quantum (discrete, uncertain...)(*) The changes to QM should for instance involve incorporating how the limits GR puts on mass concentration translate into fundamental limitations on measurement that are not present in QM in its current form.

Not including references here - see previous post, could add a couple others if useful.

 

[write4u]

(*) The changes to QM should for instance involve incorporating how the limits GR puts on mass concentration translate into fundamental limitations on measurement that are not present in QM in its current form.

This sounds entirely reasonable to me, as it is obvious that the gravity of mass concentration of matter poses limitations on QM. In that respect, GR would affect the function of QM in a reciprocal manner. Quantum causes matter, matter causes gravity, gravity affects subsequent quantum action. I can readily understand that.

However, as I uderstand it the BB was the creation of matter, and GR was a result of the spacetime relationships between that matter. As a fan of Bohm, I am partial to the concept of quantum potential of pure energy in which the Implicate is formed, which is then explicated in reality, at which time GR emerges and becomes influential on the quantum function, at least in specific cases.
Two more questions:
a) could GR exist without matter?
b) could matter exist without GR?

I want to thank all who have responded and the information provided will be helpful in my quest for understanding.

 

[wabbit]

To be honest I don't understand what you say here. And I don't think "quantum [mechanics ?] causes matter [to exist ?]" - I don't even know what this means. QM describes matter interactions or matter properties etc, it doesn't cause anything.
As to (a) yes as a mathematical theory GR works without matter, or even without anything i.e. GR can describe a theoretical vacuum - whether this is physics or "just maths" I don't know.
I don't know about (b) unless you mean "are there theories of matter that do not involve GR" but then the answer is obvious.

 

[write4u]

This sounds entirely reasonable to me, as it is obvious that the gravity of mass concentration of matter poses limitations on QM. In that respect, GR would affect the function of QM in a reciprocal manner. Quantum causes matter, matter causes gravity, gravity affects subsequent quantum action. I can readily understand that.

However, as I uderstand it the BB was the creation of matter, and GR was a result of the spacetime relationships between that matter. As a fan of Bohm, I am partial to the concept of quantum potential of pure energy in which the Implicate is formed, which is then explicated in reality, at which time GR emerges and becomes influential on the quantum function, at least in specific cases.
Two more questions:
a) could GR exist without matter?
b) could matter exist without GR?

I want to thank all who have responded and the information provided will be helpful in my quest for understanding.

p.s. I ran across a previous post by an science advisor of this forum.

1. In quantum mechanics, time and space are a fixed background. The various quantum mechanical particles all interact with one another, but do not impact the behavior of the background. General Relativity describes the interaction between this background space-time and matter. Taking this into effect, then, requires, at the very least, a massive rewriting of quantum mechanics, as it could no longer treat space and time as fixed parameters. Attempts to do this so far have largely failed (though loop quantum gravity and string theory are two candidate attempts).

2. In quantum mechanics, objects can exist in a superposition of states. General Relativity has no sense of superpositions. For example, a hydrogen atom may be in a superposition of the n=0 (ground) state and n=1 (first excited) states. These states have different energy. So if the atom is in a superposition of these two energy states, what is the gravitational field? Trying to put the gravitational field into a similar superposition of states doesn't work, at least not in the simple manner of doing this. So the answer is, at the very least, incredibly non-obvious.

I am not sure if this pertinent to the current discussion, but it seems to clarify the separate functions of QM and GR. I may be wrong.

 

[write4u]

To be honest I don't understand what you say here. And I don't think "quantum [mechanics ?] causes matter [to exist ?]" - I don't even know what this means. QM describes matter interactions or matter properties etc, it doesn't cause anything.
As to (a) yes as a mathematical theory GR works without matter, or even without anything i.e. GR can describe a theoretical vacuum - whether this is physics or "just maths" I don't know.
I don't know about (b) unless you mean "are there theories of matter that do not involve GR" but then the answer is obvious.

Thanks for the "like". It encourages me to delve deeper (see above)..

I know this is a naive viewpoint, but I always understood that matter is created and exists by means of the quantum function. I cannot imagine GR being causal to the creating of matter (except in an indirect way), as IMO, it seems to deal with the geometric relationships between matter, rather than the existence of matter itself.

 

[BiGyElLoWhAt]

Imho, I am not so sure that qm explains the cause of anything. It describes interactions, the forces, uncertainties associated with experiments. I don't see it really explaining anything like for instance why quarks are fundamental, or leptons for that matter; it just says they are.

 

[wabbit]

matter is created and exists by means of the quantum function.

I still cannot get what you mean here - read litterally it makes no sense to me : it sounds like you are ascribing to physics powers it doesn't have.
Perhaps you are thinking of creation/annihilation operators in QFT. These can be thought of as describing (certainly not causing) the creation of matter in a specific sense (I personally find it less misleading to think they describe how one aspect of matter fields, namely particle count, changes - but I'm probably splitting hairs at this point).

GR (...) seems to deal with the geometric relationships between matter, rather than the existence of matter itself.

Agreed, sounds to me like a good way to put it.

 

[write4u]

Imho, I am not so sure that qm explains the cause of anything. It describes interactions, the forces, uncertainties associated with experiments. I don't see it really explaining anything like for instance why quarks are fundamental, or leptons for that matter; it just says they are.

But even superluminal virtual particles are formed at some point and as I understand it QM is the function (not necessarily the cause) by which these particles are formed. QM is an energetic function, whereas GR is geometric function.

From what I understand, David Bohm explained the progression and conversion from waves of pure energy (holomovement) with infinite potential, from which implications form, eventually becoming explicated in physical reality, IOW, the formation of the universe as we know it to be today.

In his later career, de Broglie worked to develop a https://www.physicsforums.com/wiki/Causality_(physics) explanation of wave mechanics, in opposition to the wholly https://www.physicsforums.com/wiki/Probabilistic models which dominate https://www.physicsforums.com/wiki/Quantum_mechanical theory; it was refined by https://www.physicsforums.com/wiki/David_Bohm in the 1950s. The theory has since been known as the https://www.physicsforums.com/wiki/De_Broglie%E2%80%93Bohm_theory .

and

One of the most impressive theories emerging out of scientific cosmology respecting these ancient truths was set forth by the late physicist, David Bohm in his book, Wholeness and the Implicate Order. Using the language of mathematics, Bohm set out to describe the transcendent reality and its graded energetic hierarchy in four basic states or orders of energy beginning with the physical world, which he called the Explicate Order. (NOTE: he is working backward from the macro world of reality)

'The Explicate Order, weakest of all energy systems, resonates out of and is an expression of an infinitely more powerful order of energy called the Implicate order. It is the precursor of the Explicate, the dreamlike vision or the ideal presentation of that which is to become manifest as a physical object. The Implicate order implies within it all physical universes. However, it resonates from an energy field which is yet greater, the realm of pure potential. It is pure potential because nothing is implied within it; implications form in the implicate order and then express themselves in the explicate order. Bohm goes on to postulate a final state of infinite [zero point] energy which he calls the realm of insight intelligence. The creative process springs from this realm. Energy is generated there, gathers its pure potential, and implies within its eventual expression as the explicate order.' Will Keepin, David Bohm, Noetic Science Journal

When Bohm's resonant fields are arranged in a vibrational hierarchy they represent energy in successive states of manifestation from infinitely subtle to the gross physical reality

.

It would be reasonable to assume that the simplest particles are formed first from wave harmonics and interferences. Some particles combine and form more massive (less energetic) particles, which, due to inertia are no longer able to travel at C, and require acceleration and time to reach their natural speed.

My fundamental assumption (quite possibly wrong) is that the BB (superluminal) inflation and all matter formed within the emerging spacetime was caused by a single mega-quantum event, where everything happened all at once, and in the same place (a singularity of any size). The resulting chaos slowly ordered itself as matter began to form along with gravity from physical attraction and the expansion of spacetime metrics.

Fundametally I see QM as an energetic function, whereas GR is an emerging property along with the expansion of the universe.

If I ask myself if GR could exist (other than as a potential) prior to the BB, the answer is no as no physical objects (subject to GR) existed prior to the BB. We do know that potential for energy must have existed prior to the BB, or else the incalculable released energy could never have happened. However, this is not to say that the potential for GR did not exist prior to the BB, but only in a latent form, which emerged along with the evolution of the universe.
But again, I am open to correction.

 

[write4u]

I still cannot get what you mean here - read litterally it makes no sense to me : it sounds like you are ascribing to physics powers it doesn't have.

I am sorry, the term "creation" of matter is misleading. A better term might be "evolution" of matter and energy.

Perhaps you are thinking of creation/annihilation operators in QFT. These can be thought of as describing (certainly not causing) the creation of matter in a specific sense (I personally find it less misleading to think they describe how one aspect of matter fields, namely particle count, changes - but I'm probably splitting hairs at this point).

Agreed, sounds to me like a good way to put it.

If I may be so bold to offer a sumation: QM is a constant energetic function, GR is a relative geometric function.

This will be my last post on this subject as I do not want to hijack the thread from more erudite minds.

I'll just observe and continue to research the subject. Thanks all for your patience in dealing with this layman's view.

 

[David Miller]

I believe that one should first examine various stability conditions. This was done for instance in a recent PRD paper https://journals.aps.org/prd/abstract/10.1103/PhysRevD.93.063526. Accordingly the world model with such corrections is simply unstable.

 

[secur]

as a non-cosmologist, what do we know to a good degree of confidence, and what specifically is on the frontiers of speculation.

- it's all speculation.