Are electrons virtual particles?

[BadgerBadger92]

Since electrons pop in and out of existence, are they virtual particles?

 

[PeterDonis]

Since electrons pop in and out of existence

Why do you think they do?

 

[A. Neumaier]

See https://www.physicsforums.com/insights/misconceptions-virtual-particles/

 

[BadgerBadger92]

Why do you think they do?

Because they pop in and out of existence, yet have the property of mass.

 

[ZapperZ]

Because they pop in and out of existence, yet have the property of mass.

They don’t pop in and out of existence. The electrons that are used in synchrotron centers all over the world are kept in those storage rings for HOURS!

Zz.

 

[PeterDonis]

Because they pop in and out of existence

Why do you think they pop in and out of existence?

Hint: the answer should be something like "because of the results of experiments X, Y, Z..."

 

[Herbie]

I think I read something by Carlo Rovelli recently that seemed to suggest that electrons do behave in this way, if they can even be considered 'particles'.

Does it not follow logically from them being elementary particles with no structure, so that quantum mechanics says they can be in one place in a given moment and any other place (depending on probabilities) in the next moment - hence, 'pop in and out of existence'?

Because of this 'odd' behaviour, I actually wondered if electrons could be said to be particles at all; if, rather than existing individually, they are more like a locally occurring manifestation of the electromagnetic field.

So electrons would be where the electromagnetic field 'spikes' in correspondence with the presence of a given element, rather than being a discrete piece of matter of any kind; in which case, measuring their 'mass' would be more like measuring the temporary, local curvature of the field than measuring a particle.

 

[ZapperZ]

I think I read something by Carlo Rovelli recently that seemed to suggest that electrons do behave in this way, if they can even be considered 'particles'.

Does it not follow logically from them being elementary particles with no structure, so that quantum mechanics says they can be in one place in a given moment and any other place (depending on probabilities) in the next moment - hence, 'pop in and out of existence'?

No, it does not. Having the probability of being "smeared" over many places does NOT imply that it pops in and out of existence. Furthermore, this is NOT the de facto definition of what a "virtual particle" is. There's a whole bunch of mathematics that goes behind the term "virtual particles". It is not merely a hand-waving description of things popping in and out of existence.

In this forum, using the source "... I think I read something by Carlo Rovelli recently ... " is not considered as a valid reference. You need to make proper citation (i.e. we are trying to train people on this forum to pay attention to the source), preferably from a published research paper, to be used as a source. If Rovelli "recently" indicated such a thing, then give us a direct reference, because there's a very good chance that you misread or misinterpret what you read.

P.S. You need to re-read the PF Rules that you had agreed to before you run into trouble with this forum.

Zz.

 

[Boing3000]

Does it not follow logically from them being elementary particles with no structure,

I don't think "no structure" is a good description of an elementary particle...

so that quantum mechanics says they can be in one place in a given moment and any other place (depending on probabilities) in the next moment - hence, 'pop in and out of existence'?

I think QM says that a particle can be at many place at any moment. Because all these are probabilities that sum up to 1, there is always one particle at any moment. Nothing is pop'ping in and out. (even in tunneling)

 

[Herbie]

To Zz:

It was 'Seven Brief Lessons On Physics', by Carlo Rovelli; however, as you say, I may well have misinterpreted what I read.

Do the probabilities not tell us that a particle will not, in all likelihood, be that far from its previous interaction even though it could, possibly, be anywhere? So a particle being 'smeared' isn't really a more accurate term to use than 'popping in and out of existence'; also, it needn't be correct simply because there's some mathematics to support it.

[Mentors' note: this post has been edited to remove some off-topic comments]

 

[Nugatory]

This thread is reopened after a bit of moderation.

Please remember that the technical forums are for discussing technical topics consistent with our mission statement:

Our mission is to provide a place for people (whether students, professional scientists, or others interested in science) to learn and discuss science as it is currently generally understood and practiced by the professional scientific community.

- Challenges to this understanding are allowed only if they are supported by peer-reviewed publication.
- Unhappiness with the tone of a another member's posts or their perceived attitude should be dealt with by clicking the "report" button, not by replying.
- General suggestions about how we can better engage our wide-ranging audience in support of the mission statement should be posted to the forum feedback section.

 

[Boing3000]

So a particle being 'smeared' isn't really a more accurate term to use than 'popping in and out of existence';

No, it really is. It is very important for to distinguish between the model (the theory) and the correct words applied to it (like 'smeared'), and the words you did employ to describe 'real' thing you have in your mind that"pop in and out" (which is incorrect).

The fundamental of science is probably the conservation laws which are deeply related to various symmetries that all are formulation of physics are based on. Those conservation law still allow for dynamics that maybe seems weird like quantum fluctuation, but those are still not things that pop in and out of existence.

also, it needn't be correct simply because there's some mathematics to support it.

No, it really need be. Because the only purpose of science is the the mathematical prediction (even if only probabilities) matches observation/reality.

The current mathematical description is what it is. It works well and allow to compute real number to build really apparatus that really works.
At quantum scale, there are some hard limitation on what can be known and predicted. But one electron is really smeared out somewhat, has is simply proved by the infamous double slit experiment.

The virtual particles as quoted be the OP is an entirely different and complicated business.

 

[Herbie]

The 'pop in and out of existence' is not a "'real thing that I have in my mind" that you state.

I have already stated that I don't believe electrons to behave in this way (because I don't think that they exist, per se), but the phrase used by the original poster is supported by Mr Rovelli, in the book I referred in my previous post, in the following quotes (my bold, to highlight pertinent phrases):

"Heisenberg imagined that electrons do not always exist. They only exist when someone or something watches them, or better, when they are interacting with something else. They materialise in a place, with a calculable probability, when colliding with something else. The 'quantum leaps' from one orbit to another are the only means they have of being 'real': an electron is a set of jumps from one interaction to another. When nothing disturbs it, it is not in any precise place. it is not in a 'place' at all." (p.15); and,

"They are elementary excitations of a moving substratum similar to the field of Faraday and Maxwell. Miniscule moving wavelets. They disappear and reappear according to the strange laws of quantum mechanics..." (p.30) - here he is referring to quanta generally, but does give electrons as one example of these on page 29; and,

"A handful of types of elementary particles, which vibrate and fluctuate constantly between existence and non-existence and swarm in space even when it seems there is nothing there..." (pp.35-36).

All of which, I think, supports the phrasing of the original post.Regarding something being correct, simply because there is some mathematics to support it, I would refer you to the difficulties of the Standard Model that, according to Mr Rovelli, has:

"never been taken entirely seriously by physicists...It's made up of various pieces and equations assembled without any clear order" and makes "nonsensical predictions" (p.32) - any theory requiring mathematics that resort to 'cancelling infinities' doesn't seem to me to be all that credible a description of reality, even if it 'works' in practice.

Mr Rovelli also notes that "The equations of quantum mechanics and their consequences are used daily in widely varying fields...Yet they remain mysterious. For they cannot describe what happens to a physical system, but only how a physical system affects another physical system.

You will also note that SU5 and super-symmetry are lovely mathematical theories lacking practical proof (last time I checked) - i.e. mathematical theories aren't necessarily a good description of reality or explanation of what is actually, practically going on.So at least you can see where I'm coming from (although I don't yet acknowledge that it is a single electron (i.e. a particle) that is 'smeared out' in the double slit experiment).

All the best.

 

[ZapperZ]

Again, this is an issue of the misinterpretation of the principle of superposition. And it is ironic that you are dismissing the mathematical description, because the quote you cited is based ENTIRELY on interpreting the mathematics of QM! You can't dismiss something, and yet, use it outright in the same breath!

And it seems that the reality that we have electron storage rings at synchrotron centers all over the world is being totally ignored. I highly recommend that, if you have the opportunity, to visit one of these places and ask them if they think the electrons they have whizzing in these storage rings are popping in and out of existence. That is not based on any "mathematics", but rather based on observation.

Be very careful in playing this quotation game, especially when you do not understand the physics involved. I've worked with electron tunneling, electron photoemission, electron accelerators, and electron sources. To claim not only that they pop in and out of existence, but that they do not exist, is extremely flippant.

Zz.

 

[Herbie]

Thank you for your reply.

I have given you my evidence, so it's clear enough for people to see and judge for themselves; I refer you back to it, and do not resile from it.

I don't appreciate your tone, but it seems that some people are more 'moderated' on here than others. Bye!

 

[ZapperZ]

Thank you for your reply.

I have given you my evidence, so it's clear enough for people to see and judge for themselves; I refer you back to it, and do not resile from it.

I don't appreciate your tone, but it seems that some people are more 'moderated' on here than others. Bye!

You didn't give "evidence". You gave quotation out of context and completely misinterpret the intention. "evidence" in physics require experimental verification, not someone's else's quote! That's like citing the bible!

This is the APS storage ring status.

https://www3.aps.anl.gov/aod/blops/status/srStatus.html

They inject electrons every 12 hours, meaning that they hold electrons inside the storage ring for 12 hours in between injections. This is what I mean by evidence. It means that if you believe otherwise, you have to account for this apparent discrepancy between what you believe in, and what is observed experimentally. Otherwise, your "belief" has been falsified spectacularly by such evidence.

Zz.

 

[Boing3000]

"Heisenberg imagined that electrons do not always exist.

Nobody is giving you a hard time here just for the sake of it. You didn't even make the original claim. But here, even without going into "interpretation territory', the key word is "imagined".

They only exist when someone or something watches them, or better, when they are interacting with something else.

The keyword here is "only". This is a mistake. The theory doesn't say the electron does not exist between measurement. It is this famous interpretation debate.

They materialise in a place, with a calculable probability, when colliding with something else. The 'quantum leaps' from one orbit to another are the only means they have of being 'real': an electron is a set of jumps from one interaction to another. When nothing disturbs it, it is not in any precise place. it is not in a 'place' at all." (p.15); and,

Yes but nothing says that they de-materialize in between. It is just a probability to be found at a place, in less spooky (an prone to miss-interpretation) words

"They are elementary excitations of a moving substratum similar to the field of Faraday and Maxwell. Miniscule moving wavelets. They disappear and reappear according to the strange laws of quantum mechanics..." (p.30) - here he is referring to quanta generally, but does give electrons as one example of these on page 29; and,

A sad choice of word. They just can be observed (here then there).

"A handful of types of elementary particles, which vibrate and fluctuate constantly between existence and non-existence and swarm in space even when it seems there is nothing there..." (pp.35-36).

All of which, I think, supports the phrasing of the original post

Not really. This quote seems to be taken out of context. I don't have the full original quote, but it seems to me that this sentence is about virtual-particle (reading the article link in post #3 will help you out.

Regarding something being correct, simply because there is some mathematics to support it, I would refer you to the difficulties of the Standard Model that, according to Mr Rovelli, has:

That's not why it is correct. Math is always correct ... by definition. It is correct up to it's validation/vindication per experiment.
Mr Rovelli is not the only one to be unsatisfied be the current theory. He is free to invent a better one. Many physicist try do do that...Meanwhile, the best there is is QFT.

So at least you can see where I'm coming from (although I don't yet acknowledge that it is a single electron (i.e. a particle) that is 'smeared out' in the double slit experiment).

And yet, there is no escaping simple logic. You have to explain how one thing can go trough two slit to interfere with itself. An extension of QM kind of try to remove the "smearing" at the expense of electron trajectory being as weird as a simple "probability wave packet".

 

[Nik_2213]

Um, if a virtual electron popped out of the quantum soup, would there not be an associated positron ?

 

[PeterDonis]

It was 'Seven Brief Lessons On Physics', by Carlo Rovelli; however, as you say, I may well have misinterpreted what I read.

Not only that, this is a pop science book, not a textbook or peer-reviewed paper. You can't learn science from a pop science book. Even the best of them will mislead you if you don't already understand the actual science--the mathematical models and the experimental data--that the pop science book is trying to describe in lay person's language.

 

[Herbie]

Since I haven't any access to peer-reviewed material or any actual first-hand observational evidence (as I am not a physicist; and I think this is or was a thread for novices), here's another book from the library that I was reading this week: particle-physicist/cosmologist Lisa Randall's Knocking on Heaven's Door (2011). A couple of passages seemed relevant to this discussion:

"Quantum mechanics tells us that the vacuum - the state with no permanent particles present - is actually filled with ephemeral particles that pop in and out of existence. These short-lived particles can have any energy." (p. 374). I chuckled to see this exact phrase and I wondered if this was a common phrase used in physics, but to be fair to her the context here is vacuum, dark energy and dark matter, and she doesn't mention electrons as doing the 'popping-in-and-out'.

The other was relating to the hierarchy problem of the Standard Model of particle physics:

"Calculations based on quantum mechanics and special relativity tell us that without a richer theory, masses should be much greater - in fact, 10 quadrillion...times as big. The theory only hangs together with an enormous fudge physicists unabashedly call "fine tuning". " (p.118).

This point seems, to me anyway, to support the point I was making with the following quote I gave from Carlo Rovelli (but failed to edit/attribute properly):

"The equations of quantum mechanics and their consequences are used daily in widely varying fields...Yet they remain mysterious. For they do not describe what happens to a physical system, but only how a physical system affects another physical system. (2016; p.18)...

...which - to me, anyway - both speak to the idea I was trying to convey that mathematics and probability are not necessarily enough to explain a scientific process: they can be expedient, lack thoroughness and rigour about what is actually, physically, happening. If quantum mechanics and the Standard Model are the best that we have then fine, but I don't like the apparent suggestion on this thread that they amount to any more than that basic tenet of science - provisional.

Finally, my misconceptions about the Standard Model seem to be highlighted by the summary diagram of the Standard Model - given on Figure 46 (p.254-255).

I had surmised that each field had not only a boson to carry the force, but also a fermion to carry the charge/mass (e.g. Fields: Strong/HiggsWeak/EM/Gravitation -> Forces: gluon/HiggsBoson/photon/graviton -> Charges: quark/W+W-Z/electron/gravity), but it seems that Higgs and Weak forces are actually separate - oh dear! But I still don't think electrons are anything more that the 'charged' electromagnetic field, and so the same 'electron' can't be observed twice (hence, why they can seem to - but do not - reappear in any given place) - but that's probably just my ignorance again!

 

[weirdoguy]

particle-physicist/cosmologist Lisa Randall's Knocking on Heaven's Door (2011).

Which is a pop-science book and everything that @PeterDonis said holds. The very first thing you wrote:

Quantum mechanics tells us that the vacuum - the state with no permanent particles present - is actually filled with ephemeral particles that pop in and out of existence.

It's pure pop-science nonsense, and it's been debunked here a lot of time. I'm wondering what makes some physicists think that just because they write to lay-people they can write such things. PhysicsForums is a great place to learn, but the way to do this is not to argue with specialists based on such books.

both speak to the idea I was trying to convey that mathematics and probability are not necessarily enough to explain a scientific process: they can be expedient, lack thoroughness and rigour about what is actually, physically, happening.

1. Define "actually, physically happening".
2. If you put enough thought in that, you will realize that mathematics is the best thing we have.

But I still don't think electrons are anything more that the 'charged' electromagnetic field (...) but that's probably just my ignorance again!

Quantum electrodynamics is quite old, so we know for quite a long time what is the difference between electrons (electron field) and electromagnetic field. If you still want to ignore that fact that would make you an ignorant. But I'm sure you don't want to ignore it

 

[PeterDonis]

Since I haven't any access to peer-reviewed material

Sure you do. Go to arxiv.org.

Also, you can look at textbooks.

I think this is or was a thread for novices

It's a "B" level thread which means that only high school level knowledge is assumed. But that doesn't make pop science books valid sources. The PF rules for what are valid sources apply regardless of the level of the thread.

here's another book from the library that I was reading this week: particle-physicist/cosmologist Lisa Randall's Knocking on Heaven's Door (2011).

This is another pop science book and has the same issues we've already discussed.

I still don't think electrons are anything more that the 'charged' electromagnetic field

No. The electron field and the electromagnetic field are different fields. The particle that corresponds to the electromagnetic field is the photon, which has no charge.

 

[Herbie]

It's pure pop-science nonsense, and it's been debunked here a lot of time. I'm wondering what makes some physicists think that just because they write to lay-people they can write such things. PhysicsForums is a great place to learn, but the way to do this is not to argue with specialists based on such books.

I hadn't realized I was arguing with specialists on Physics Forums: the typical forum is full of non-specialists like myself, quoting the supposed specialists who write books or articles on their given subjects and discussing from there. So, that's what I thought was happening here.

1. Define "actually, physically happening".
2. If you put enough thought in that, you will realize that mathematics is the best thing we have.

By actually, physically happening I meant any method that resorts to renormalisation (which I've seen mathematicians refer to as a mathematical "trick") and cancelling infinities seems unlikely to be an accurate description of the underlying natural process that links cause and effect.

Whether mathematics is or not the best thing that we have, it doesn't mean that it is necessarily appropriate to use it in such a seemingly glib way to deal with an unknown process. Mathematics also has had its issues with set theory/Russell's paradox, incompleteness theorems, and a seemingly irrational inability to accept the evidence supporting the Riemann hypothesis - could take lessons from science in this regard!

Quantum electrodynamics is quite old, so we know for quite a long time what is the difference between electrons (electron field) and electromagnetic field. If you still want to ignore that fact that would make you an ignorant. But I'm sure you don't want to ignore it

Fine - yes, I am - but the point was really that it is the field rather than a particle that is being measured, which leads to infinities, which leads to physicists looking for mathematical work-arounds rather than accepting that the results don't fit their model and thinking again. As I said, fine - but 'tis provisional.

Sure you do. Go to arxiv.org.Thank you, I will look at this.Also, you can look at textbooks.

I don't have access to textbooks at this time.

No. The electron field and the electromagnetic field are different fields. The particle that corresponds to the electromagnetic field is the photon, which has no charge.

Okay, I thought the electron field was a subset of the electromagnetic field such that the photon carried the force (boson), whilst the electron 'field' carried the charge (fermion).

In the same way I thought that the graviton carried the force of the gravitational field/spacetime, whilst gravity+ and antigravity- were the charge carriers/fermions for that field (hence, continuing inflation of the universe through uniform spread of antigravity- charge throughout the universe, offsetting the more focused gravity+ charge found with concentrated masses of matter-energy).

But, then, I thought that the Higgs field and the Weak field were two sides of the same coin: charge-to-matter (Higgs) and matter-to-charge (Weak)...ho-hum!

 

[Vanadium 50]

By actually, physically happening I meant any method that resorts to renormalisation (which I've seen mathematicians refer to as a mathematical "trick") and cancelling infinities seems unlikely to be an accurate description of the underlying natural process that links cause and effect.

Herbie, Herbie, Herbie. You're just digging deeper. What you describe is regularization, not renormalization. It's true that many pop-science books get this wrong too, and it's not really your fault, but that's in the opposite direction to what you are arguing.

Since this is just another one of BadgerBadger's annoying drive-bys, and that it's been answered, maybe we should close this thread?

 

[PeterDonis]

I thought the electron field was a subset of the electromagnetic field such that the photon carried the force (boson), whilst the electron 'field' carried the charge (fermion).

Nope, that's not the way it works. I described the way it works.

In the same way I thought that the graviton carried the force of the gravitational field/spacetime

Gravitons are speculative; we do not have a confirmed quantum field theory of gravity the way we do for the other interactions.

gravity+ and antigravity- were the charge carriers/fermions for that field (hence, continuing inflation of the universe through uniform spread of antigravity- charge throughout the universe, offsetting the more focused gravity+ charge found with concentrated masses of matter-energy).

I don't know where you got this from. It's nonsense.

But, then, I thought that the Higgs field and the Weak field were two sides of the same coin: charge-to-matter (Higgs) and matter-to-charge (Weak)...ho-hum!

This is nonsense too.

 

[PeterDonis]

I hadn't realized I was arguing with specialists on Physics Forums: the typical forum is full of non-specialists like myself, quoting the supposed specialists who write books or articles on their given subjects and discussing from there. So, that's what I thought was happening here.

Not all posters on PF are "specialists" (in the sense of being scientists actively engaged in research). I'm not. However, I and the other people who are trying to correct you have taken the time to build an understanding of what the science on the topic of this discussion actually says, by working through textbooks and peer-reviewed papers instead of reading pop science books. A pop science book is not a valid source for learning science, even if it's written by a scientist. So if on other forums you are used to people quoting pop science books as though that gave them actual knowledge of the science, I guess PF is not like other forums. But our rules are what they are and we have them for good reasons.

I don't have access to textbooks at this time.

That doesn't mean it's ok to use pop science books as sources here. It isn't.

 

[PeterDonis]

Since the OP is gone and nothing useful is being discussed at this point, this thread is closed.