Insights The Vacuum Fluctuation Myth - Comments

[mfb]

The concept of virtual particles is well-defined and useful when restricted to its use in Feynman diagrams and associated technical discussions. But it is highly misleading when used to argue about vacuum fluctuations, as if these were processes happening in space and time.

I agree. Peter's post looked much more general, however, including Feynman diagrams.

 

[vanhees71]

So would you like to hear my theory on what virtual particles are? I offered to explain this to D. J. Griffiths, as he is a neighbor of mine, but he has mysteriously remained silent.

Well, Griffiths may be busy with his research and teaching at the university, and from my own experience I can say that if somebody comes by my office, whom I've never seen in my live before, saying he "wants just to discuss about Einstein/relativity, quantum theory, etc." I always pretent to have no clue about these subjects. Then they leave my office quickly. Once, when I was still a diploma student, I was uncareful enough to answer an email of this type. The guy claimed (first indication of a dangerous person) that he had "disproven Einstein", and that he wanted to present his theory to me. I read the rest of the long e-mail, and it was garbage. Then I answered him, explaining what's garbage. That wasn't a good idea, because I got swamped with e-mails of the guy, which at one point I simply ignored. One day, he appeared in person, and it took the whole afternoon to get finally rid of him. Understandably that's why physicists tend to ignore such attempts to disproved established science. So Griffiths's "silence" is everything else than mysterious, it's shear self-defence against unnecessary distruction from work ;-).

 

[Mordred]

Um you quoted someone else that isn't my quote lol

 

[A. Neumaier]

Not all models in cosmology are semiclassical Loop quantum gravity certainly isn"t

My statement was made in context. Loop quantum gravity makes no assertion about Higgs.

 

[Mordred]

Oh and what about field of quantum geometrodynamics? Or the following equation from a LQC article.

\stackrel{Action}{\overbrace{\mathcal{L}}} \sim \stackrel{relativity}{\overbrace{\mathbb{R}}}- \stackrel{Maxwell}{\overbrace{1/4F_{\mu\nu}F^{\mu\nu}}}+\stackrel{Dirac}{\overbrace{i \overline{\psi}\gamma_\mu\psi}}+\stackrel{Higg's}{\overbrace{\mid D_\mu h\mid-V\mid h\mid}} +\stackrel{Yugawa-coupling}{\overbrace{h\overline{\psi}\psi}}

I suppose next your going to claim that The entire findings of a virtual particle cloud in a proton shown by LQCD is wrong too

 

[PeterDonis]

It is challenging to answer "how does a neutron decay" or "how does the study of rare decays helps with new physics searches" without the concept of virtual particles.

I don't see why it should be. For example, I learned about neutron decay in my nuclear physics classes in college without anyone ever mentioning virtual particles.

the experts you mention later are using the concept of virtual particles exactly in those cases.

As I said, they're experts. My post was directed at non-experts.

 

[A. Neumaier]

Oh and what about field of quantum geometrodynamics? Or the following equation from a LQC article.

\stackrel{Action}{\overbrace{\mathcal{L}}} \sim \stackrel{relativity}{\overbrace{\mathbb{R}}}- \stackrel{Maxwell}{\overbrace{1/4F_{\mu\nu}F^{\mu\nu}}}+\stackrel{Dirac}{\overbrace{i \overline{\psi}\gamma_\mu\psi}}+\stackrel{Higg's}{\overbrace{\mid D_\mu h\mid-V\mid h\mid}} +\stackrel{Yugawa-coupling}{\overbrace{h\overline{\psi}\psi}}

You chase me through the whole physics literature... But this is the last time I answer. My context was your comment ''There are numerous professional researches ongoing on the aspects of the Higgs field I just mentioned.'' (and the aspects you had mentioned were ''the non zero VeV of the Higg's field'' and ''that due to the non zero VeV we may be in a false vacuum state.'' I see none of these in the formula you just displayed. Note that a ''false vacuum state'' does not belong to the set of physical states of a field theory since it is incompatible with causality. Hence we cannot be in such a state.

 

[Mordred]

I'm chasing you through these branches of physics because your inplying they are all wrong. As they do not consider virtual particles as just internal lines on a feyman diagram. That individual virtual particles do not have sufficient momentum to cause action. Collectively in a finite volume they can

 

[rubi]

I'm chasing you through these branches of physics because your inplying they are all wrong. As they do not consider virtual particles as just internal lines on a feyman diagram. That individual virtual particles do not have sufficient momentum to cause action. Collectively in a finite volume they can

LQG has neither Feynman diagrams nor virtual particles.

 

[Mordred]

then how do explain spinfoam action below a quanta of energy? How do you account for any energy/density below a quanta? You certainly cannot state energy exists on its own as energy is a property.

https://arxiv.org/abs/1201.4598

"This means that, although individual terms in the perturbation expansion of a physical amplitude may diverge due to radiative corrections involving closed loops of virtual particles, "

Direct quote from the "Introductory to loop quantum cosmology" article.

 

[rubi]

then how do explain spinfoam action below a quanta of energy? How do you account for any energy/density below a quanta? You certainly cannot state energy exists on its own as energy is a property.

None of these questions make sense.

https://arxiv.org/abs/1201.4598

"This means that, although individual terms in the perturbation expansion of a physical amplitude may diverge due to radiative corrections involving closed loops of virtual particles, "

Please don't just type "virtual particle" into the search field of your PDF viewer and randomly quote sentences. If you had read Abhay's article, you would have seen that he is talking about a completely different theory and not about LQG. And he explains that this different theory was not successful. Moreover, even if it was, the Arnold's comments would still apply to it.

 

[weirdoguy]

I'm chasing you through these branches of physics because your inplying they are all wrong.

Well, so almost every textbook on QFT imply "they are all wrong"... Have you taken any course in quantum field theory? Because as far as I can see, only people who haven't have issues with what A. Neumaier wrote in his insights. All those who really learned QFT during their studies agree with what he wrote. That's weird, isn't it?

 

[Mordred]

Oh really then he can answer my concerns on these branches of physics and how more than a few physicists state virtual particles are real and not just internal lines.

Considering he is specifically stating they are wrong to do so. That's not an unreasonable request

 

[OmCheeto]

Um you quoted someone else that isn't my quote lol

That was me he was quoting.

Well, Griffiths may be busy with his research and teaching at the university, and from my own experience I can say that if somebody comes by my office, whom I've never seen in my live before, saying he "wants just to discuss about Einstein/relativity, quantum theory, etc." I always pretent to have no clue about these subjects. Then they leave my office quickly. Once, when I was still a diploma student, I was uncareful enough to answer an email of this type. The guy claimed (first indication of a dangerous person) that he had "disproven Einstein", and that he wanted to present his theory to me. I read the rest of the long e-mail, and it was garbage. Then I answered him, explaining what's garbage. That wasn't a good idea, because I got swamped with e-mails of the guy, which at one point I simply ignored. One day, he appeared in person, and it took the whole afternoon to get finally rid of him. Understandably that's why physicists tend to ignore such attempts to disproved established science. So Griffiths's "silence" is everything else than mysterious, it's shear self-defence against unnecessary distruction from work ;-).

I can assure you, that I have no "theories" of my own.
I would describe my thoughts as; "hmmmmmm... Perhaps these quantum physicists can visualize extra dimensions, which we mere mortals, can not".

Have you ever seen this video?



Things don't make sense, when seen in two dimensions, when they are three dimensional.
I imagine that Quantum Mechanics, being hyper-dimensional, IMHO, is kind of like that.

ps. The "" at the end of my comment should have clued you in that his actions, were totally understandable.

 

[Mordred]

So Neumaiur are you going to address the issue that although an individual virtual particle doesn't cause action a group of virtual particles can ?
This is precisely what I have been trying to get you to answer.

Is that not what the field perturbations of a S matrix describing?
field/perturbations generically described as virtual particles and field excitations generically a real particle?

 

[Mordred]

You chase me through the whole physics literature... But this is the last time I answer. My context was your comment ''There are numerous professional researches ongoing on the aspects of the Higgs field I just mentioned.'' (and the aspects you had mentioned were ''the non zero VeV of the Higg's field'' and ''that due to the non zero VeV we may be in a false vacuum state.'' I see none of these in the formula you just displayed. Note that a ''false vacuum state'' does not belong to the set of physical states of a field theory since it is incompatible with causality. Hence we cannot be in such a state.

Where are you getting incompatible with causality from? Are you ignoring multiparticle system states? Why can't you have a global distribution of field perturbations?

Which brings us right back to my original post which you called gibberish.

I reiterate there are no particles only fields. Soeaking of my original post you objected to. What do you call the propogator contributions of field perturbations ie how off shell the particle is
https://en.m.wikipedia.org/wiki/Propagator

http://www.google.ca/url?sa=t&source=web&cd=14&ved=0ahUKEwisvJjWzrvRAhXEw1QKHS4xAagQFghOMA0&url=http://www-pnp.physics.ox.ac.uk/~barra/teaching/feynman.pdf&usg=AFQjCNFXFEf7xQrDFKy1hG1mb6SlMwmSKg&sig2=3Ia1ETeyUQaCxwSZR3GFUA

is the propogator not a plane wave? Yet you stated their is no wavefunction for virtual particles in your reply to my original post.

 

[sanman]

A. Neumaier submitted a new PF Insights post

Hi Arnold, I really want to thank you for this article, as I find the topic of the Vacuum (or spacetime) to be truly interesting.

It was physicist Andrei Sakharov who said "the mysteries of the vacuum will be the great challenge for 21st-century physics"

But after having read you tell me what I shouldn't believe, I then really want to know what I should believe.
You've just told me why it's wrong to believe that 6 x 7 = 45 and I hear you on that. But now I want to know what the actual answer is.

And as far as I can see, you're not explicitly saying "the answer isn't 45" - you're instead saying "we as yet have no reason to believe it's 45"

So I'm looking for someone to tell me what the Vacuum is actually made out of, if it's not made out of "virtual particles".

 

[Mordred]

removing all matter a scalar field would be my answer

 

[A. Neumaier]

what the Vacuum is actually made out of, if it's not made out of "virtual particles".

It is made of nothing, it is just a container for real stuff. You could as well ask what the interior of an empty bottle contains.

 

[sanman]

removing all matter a scalar field would be my answer

Okay, but what is causing/producing the scalar field? There seem to be fluctuations happening in the Vacuum - Black Body radiation indicates this. DeBroglie wavelength of objects also seems to indicate this. So what is that stuff? What is causing these fluctuations/disturbances in the Scalar Field?

 

[sanman]

It is made of nothing, it is just a container for real stuff. You could as well ask what the interior of an empty bottle contains.

But conceptually, a bottle doesn't need to have black body radiation - the fact that it does says there is something more than the bottle which is there.
Conceptually, a bottle doesn't need to have a Casimir force inside it - the fact that it does says there is something more than bottle which is there.

I feel as if you've just told me to ignore that photons have wave characteristics - ie. "just ignore it, this is a mere artifact of observation, and doesn't signify anything"

I cannot ignore it, I cannot pretend it isn't there - I want to know what's causing it. I want to know if whatever's causing it has its own deeper properties, which perhaps I can't immediately/easily see.

 

[A. Neumaier]

Okay, but what is causing/producing the scalar field?

The fields are there, all the time. The vacuum state is just the special state of the system where the state is Poincare invariant - timeless, spaceless, due to the symmetry. This is like an empty, infinitely extended container - an abstraction.

Real spacetime is nowhere a vacuum. it is filled everywhere with fields - gravity, radiation, and traces of matter - with big lumps here and there. These fields are not in a pure vacuum state, however, not even locally, far away from stars and planets.

If you ask for a cause of that, you need to ask God. The answer is outside the realm of physics.

 

[A. Neumaier]

a bottle doesn't need to have black body radiation - the fact that it does says there is something more than the bottle which is there.

It says that the bottle has an exterior which is not empty, from which the radiation comes. This means that a real bottle is not really empty. The bottle I was talking about was an abstraction, just like the vacuum of quantum field theory.

So, the effects in an apparent piece of vacuum (apparent since there are invisible fields in any vacuum that can be created experimentally) between pieces of matter are caused by the matter and fields surrounding the vacuum,.

 

[sanman]

The fields are there, all the time. The vacuum state is just the special state of the system where the state is Poincare invariant - timeless, spaceless, due to the symmetry. This is like an empty, infinitely extended container - an abstraction.

Real spacetime is nowhere a vacuum. it is filled everywhere with fields - gravity, radiation, and traces of matter - with big lumps here and there. These fields are not in a pure vacuum state, however, not even locally, far away from stars and planets.

If you ask for a cause of that, you need to ask God. The answer is outside the realm of physics.

Sir, I don't wish to invoke a metaphysical explanation, I feel that physics and the scientific method can probe everything usefully.

Blackbody radiation can be measured reliably, and isn't overly dependent on whatever combination of cosmic events (radiating suns, exploding stars, black holes) may be happening around the rest of the cosmos at the time.
Casimir force can be measured reliably, and experimental observation of it doesn't give radically different results when done with appropriate experimental rigor.

Furthermore, the very ideas of waves or particles or fields are themselves concepts we apply onto reality. If I choose to call an automobile a particle, then that's my choice, and as long as I maintain a logical consistency, then I can describe the universe that way.

Saying that it's wrong to choose to describe Vacuum fluctuations with particles, is like saying it's wrong to describe light using photon particles.
If the fluctuations of the Scalar Field exist, then there's no reason why the idea of particles can't be adopted to describe it.

 

[A. Neumaier]

Blackbody radiation can be measured reliably

Black body radiation is caused by the electromagnetic field. Hawking radiation is real particles created by the gravitational field. Nothing is created by either the vacuum or by virtual particles.
That's the scientific part.

But you wanted a cause for the field itself, which is metaphysics.

 

[sanman]

It says that the bottle has an exterior which is not empty, from which the radiation comes. This means that a real bottle is not really empty. The bottle I was talking about was an abstraction, just like the vacuum of quantum field theory.

So, the effects in an apparent piece of vacuum (apparent since there are invisible fields in any vacuum that can be created experimentally) between pieces of matter are caused by the matter and fields surrounding the vacuum,.

What if all matter in the universe is reduced to absolute zero in temperature - will Vacuum Fluctuations cease?
What if all matter in the universe is removed from spacetime - will spacetime cease to exist, or at least its Vacuum Fluctuations?

 

[A. Neumaier]

If you remove all matter from spacetime there will still be the electromagnetic and the gravitational field. But no one to observe it, so no physics.

Absolute zero is a fiction like the vacuum itself. One cannot reach it, only approach it.

This has nothing to do with vacuum fluctuations, which are not things happening.

 

[sanman]

Black body radiation is caused by the electromagnetic field. Hawking radiation is real particles created by the gravitational field. Nothing is created by either the vacuum or by virtual; particles.
That's the scientific part.

Sir, I feel your assertion is no less metaphysical than mine. You want to assert that fluctuations are intrinsic to the field, and cannot be conceptually distinguished from it. By the same token, you could also say that energy is an intrinsic property of all matter, and doesn't deserve to be discerned or distinguished from matter. At that point, it does feel like arguing a religious debate.

But you wanted a cause for the field itself, which is metaphysics.

Sir, I'm not as immediately concerned with a cause for the field as I am with why it fluctuates and doesn't remain at a mathematical zero.
Your assertion that it's the presence/influence of other things in the universe that cause the fluctuations, doesn't explain the consistency between the various experimental measurements that have been made over time on these fluctuations, nor does it explain the anisotropic characteristics observed, in spite of matter not being homogenously distributed across the universe.

 

[A. Neumaier]

I'm not as immediately concerned with a cause for the field as I am with why it fluctuates

Fields fluctuate because this is a general property of fields. Asking about their causes is as meaningless as asking about why sine waves oscillate. It is because they are defined that way.

 

[sanman]

If you remove all matter from spacetime there will still be the electromagnetic and the gravitational field. But no one to observe it, so no physics.

Absolute zero is a fiction like the vacuum itself. One cannot reach it, only approach it.

This has nothing to do with vacuum fluctuations, which are not things happening.

Alright, to use your parlance - would the "minimal background fluctuations in the field" cease to exist under any circumstances?

It seems like a Chicken-and-Egg argument: Is the Field the basis for the fluctuations, or are the fluctuations the basis for the Field?

It's like arguing over whether Light is "a particle with wave-like characteristics" versus Light being "a wave with particle characteristics"

 

[A. Neumaier]

It seems like a Chicken-and-Egg argument: Is the Field the basis for the fluctuations, or are the fluctuations the basis for the Field?

No chicken or egg. Fluctuations are definable only after one has already defined fields. Without fields the notion of fluctuations wouldn't make scientific sense.

 

[sanman]

No chicken or egg. Fluctuations are definable only after one has already defined fields. Without fields the notion of fluctuations wouldn't make scientific sense.

That assumes they are just mere fluctuations, and not manifestations of something deeper (eg.virtual particles), which could be the basis for the Field.

We have already seen that light is quantized as photons - which is the reason that particle model has been accepted.
When the background fluctuations in the field are also quantized, why should we imagine such quantization is an intrinsic property of the field, without being open to accepting a particle model to explain the quantization?

 

[ftr]

Neumaier, I have few questions.

1. in your FAQ there is nothing about vacuum polarization, can you explain it from your point of view.

2. in QED we assume an "associated" EM field for the electron. It seems this field is a kind of pseudo-field because no real photon but a VP as its quanta, am I right.

3. do you agree that VP if they do not exist but some kind of a disturbance is generated which could be due to above field or equivalently to "vacuum fluctuation". this a view of Matt Strassler I think.

 

[A. Neumaier]

1. in your FAQ there is nothing about vacuum polarization, can you explain it from your point of view.

Vacuum polarization is the name for the radiation corrections to the photon self-energy. If computed in perturbation theory, it is given by the sum of all Feynman diagrams with two external photon lines. It is a physical effect caused by the interaction with the electron field, not by the virtual particles in the diagrams, which are pure mnemonic for the integrals used for the computation and play no causal role.
The tale told by the wikipedia page linked to is just a fairy tale, of the same kind as the myth about Hawking radiation that I discussed in the Insight article.

2. in QED we assume an "associated" EM field for the electron. It seems this field is a kind of pseudo-field because no real photon but a VP as its quanta, am I right.

I never heard about associated e/m fields for the electron. In QED there is just a single electromagnetic field and a single electron-positron field.

3. do you agree that VP if they do not exist but some kind of a disturbance is generated

The hypothesis ''they do not exist'' is false, hence there is nothing to agree to.

 

[A. Neumaier]

manifestations of something deeper (eg.virtual particles), which could be the basis for the Field.

Fields are deeper concepts than both fluctuations or virtual particles, hence the latter cannot be the basis for the former.

 

[A. Neumaier]

in your FAQ there is nothing about vacuum polarization

I just added at the end of my insight article The Physics of Virtual Particles relevant definitions of this and related items.

 

[PeterDonis]

That assumes they are just mere fluctuations, and not manifestations of something deeper (eg.virtual particles)

You are assuming that these are two different possibilities--two different ways the universe could be, and we have to figure out which.

What Arnold is saying is that they are just two different ways of trying to describe, heuristically, in ordinary language, the same single way the universe is. There is no actual difference in the physics; the only difference is in the words.

 

[ftr]

In QED there is just a single electromagnetic field and a single electron-positron field.

Ok, this is from wiki QED
https://wikimedia.org/api/rest_v1/media/math/render/svg/9277f5286335ab99c040c9c9151ab752d3bedc49 A_mu is the covariant four-potential of the electromagnetic field generated by the electron itself; do you agree with that?

Also you say

vacuum fluctuations (= nonzero vacuum expectation values)

Reference https://www.physicsforums.com/insights/vacuum-fluctuation-myth/
But I think people mean VF by the variance not the EV.

 

[Mordred]

You are assuming that these are two different possibilities--two different ways the universe could be, and we have to figure out which.

What Arnold is saying is that they are just two different ways of trying to describe, heuristically, in ordinary language, the same single way the universe is. There is no actual difference in the physics; the only difference is in the words.

Oh how true this is unfortunately often trying to describe things heuristically can cause greater confusion. I've been quilty of that on more than one occasion.

At Neumaiur now that I have a better handle on what you trying to express to me. I rectract my concerns.

 

[A. Neumaier]

vacuum fluctuations (= nonzero vacuum expectation values)

I never equated the two. Note that a nonzero variance $\sigma(X)$ is a special case $\langle(X-\bar X)^2\rangle$ of a nonzero vacuum expectation value. I clarified the final piece of my addendum to the insight article.

''The covariant four-potential of the electromagnetic field generated by the electron itself'' is sloppiness on the part of Wikipedia. The term is used solely to distinguish it from the external field mentioned in the same sentence. There is no way to separate the two parts of the field and only their sum has a measurable, hence physical meaning.

 

[ftr]

The fact that there is a variance does indicate that there is fluctuation, doesn't it

There is no way to separate the two parts of the field and only their sum has a measurable, hence physical meaning

do you mean the electron field and the EM field together "added", but the electron field does not "generate" EM.
Arnold, I think people appreciate very much what you have been trying to do, even though the issues you raised in your insight is very well known and debated endlessly but you have put them in a nice prospective story to highlight several interconnected concepts mainly regarding Feynman diagrams which were suppose to make things easier.

I also understand that it might become tiring for you, but an elaborated response might actually shorten to back and forth responses. Thank you again.

 

[Mordred]

D'oh I feel like an idiot I completely forgot the creation/annihilation operators add/subtract a quanta of energy. How embarrassing.

Ok I fully understand where you are coming from Neumaiur with regards to virtual particles.

 

[A. Neumaier]

The fact that there is a variance does indicate that there is fluctuation, doesn't it

In principle it could be interpreted as a fluctuation of the measurement results in repeatedly prepared copies of the system in identical states. But this is a sensible interpretation only for tiny systems of which one can prepare many copies in the same state. One cannot copy a quantum field. It exists only once at each point in spacetime. What is measured is always a (smeared) field expectation value. If something fluctuates there then due to turbulence, which indeed is a random field phenomenon happening in space and time. But turbulence is absent in a vacuum.

do you mean the electron field and the EM field together "added", but the electron field does not "generate" EM.

No. I mean the mathematical sum (no quotation marks) of the two physically inseparable pieces of the electromagnetic field mentioned in Wikipedia in the context of your quote, denoted there $A_\mu$ and $B_\mu$. The electron field is $\psi$ and is a separate entity that cannot be added to the e/m field as it has a completely different transformation behavior.

the issues you raised in your insight are very well known and debated endlessly but you have put them in a nice prospective story to highlight several interconnected concepts

The purpose of these insight articles is to put an end to this seemingly endless debate. Debates are always signs of using a language so imprecise that people continuously misunderstand each other. Once a clear and sufficiently authoritative language becomes widespread, misunderstanding begin to cease and debate becomes as pointless as debating irrational or imaginary numbers. The language exists already but is diluted so much by current informal practice that attempting to make sense of the whole mess is immensely confusing. It took me many years of wading through this confusion before I learned to understand things in such a way that I can point to the sources of misunderstanding in a consistent and hopefully convincing way.

 

[sanman]

You are assuming that these are two different possibilities--two different ways the universe could be, and we have to figure out which.

What Arnold is saying is that they are just two different ways of trying to describe, heuristically, in ordinary language, the same single way the universe is. There is no actual difference in the physics; the only difference is in the words.

But that's actually what I said, and not him. I pointed out that applying a particle model is just a way of describing something. He said that there can only be a Scalar Field.

Whether you want to describe the fluctuations as fluctuations in the Scalar Field, or whether you want to describe them as Virtual Particles, is just a matter of perspective.

But I would argue that quantization tends to push you towards particles, since there's no inherent need for waves to be quantized.

 

[PeterDonis]

Whether you want to describe the fluctuations as fluctuations in the Scalar Field, or whether you want to describe them as Virtual Particles, is just a matter of perspective.

No, it isn't. The scalar field is the fundamental object. "Virtual particles" is just a shorthand way of describing particular things that arise in a particular approximation.

I would argue that quantization tends to push you towards particles, since there's no inherent need for waves to be quantized.

You are making the common mistake of equating "quantized" with "discrete". That's not what quantization means.

From the standpoint of quantum field theory, quantum fields (of which the scalar field is one) are the fundamental objects. "Particles" and "waves" are just names for particular kinds of quantum field states, and there are quantum field states that are not aptly described by either of those names.

 

[Mordred]

To just add a caveat to Peterdonis excellent reply. There is alway a field even without fluctuations/particles etc. Just to stress the field is fundamental.

 

[ftr]

Arnold, I found this paper(researching a different subject) by Jaynes which you mention his name in context of entropy issues in FAQ. But This paper has some relevance to the discussion, what do you think(I kind like what he is saying, but I need to study it more)

http://bayes.wustl.edu/etj/articles/prob.in.qm.pdf

 

[sanman]

To just add a caveat to Peterdonis excellent reply. There is alway a field even without fluctuations/particles etc. Just to stress the field is fundamental.

But Mr Neumaier said that the fluctuations are intrinsic to the field. I'm saying they should be discerned from the field.

 

[Mordred]

Yes he is absolutely correct fluctuations are intrinsic to the field. Fluctuations however do not form nor define a field. Fluctuations is a property of a field much like volume is intrinsic to a 3d object. It isn't separate but an aspect of a field.

 

[sanman]

Yes he is absolutely correct fluctuations are intrinsic to the field. Fluctuations however do not form nor define a field. Fluctuations is a property of a field much like volume is intrinsic to a 3d object. It isn't separate but an aspect of a field.

He's saying there's no reason to look for a cause for those fluctuations - ie. we should just accept them "as is".

Why shouldn't we attribute a cause to the fluctuations? It's like saying there's no need to talk about energy separately from matter, because all matter is endowed with energy in some form or other.

The field may have fluctuations, but we may wish to ask why. He's saying we shouldn't ask why. To me, that's ridiculous - why can't I look for the reason why?