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I'm not a physicist, I don't know if this will make a lot of sense, so bear with me.

I'm just reading about how particles like the photon, electron, graviton, etc are each associated with their own fields. The gravity field can have a dent in it like the one caused by a massive body or waves traveling through it, gravitational waves. Now is a electron for instance a dent or a wave in the electron field? And what is the other one? For instance if the electron is the wave (which would make sense given the interference in the two slits experiment), then is there such a thing as an electron dent? What would it correspond to?

UPDATE:

It would be so elegant if say an electron, was a dent, a peak on the electron field, with a corresponding dent in the EM field (since it has charge) and a corresponding dent in the gravitational field (since it has mass). That way moving a electron up and down would create waves in the EM field (photons) just like moving a mass would create waves in the gravitational field.

Felipe Reigosa
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    By way of trying to understand what you're getting at, let me guess what your question would mean for the EM field --- I'm guessing that the contribution of a non-accelerating point charge is what you'd call a "dent" and light is what you'd call a "wave". Yes? – WillO Jun 26 '20 at 20:42
  • @WillO Exacly, that's what I was thinking. – Felipe Reigosa Jun 26 '20 at 21:25

2 Answers2

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The wave is the probability of finding the electron. This is for me one of the most difficult aspects of Quantum Mechanics, so it could need more research for a non-phisicist, but the canonical description of QM describes the waves whose evolutions are regulated by the Schrödinger's equation as probability waves. The reason why you find more electrons in the area of "peak" of the wave and less in the "dent" in the 2 slits experiment is because the electron has a lower probability of being there. When measured though, the wave collapses, meaning that becomes zero everywhere except for a specific point: that point is more likely to be in the peak than in the dent, and that point is the electron.

I didn't understand your analogy with the graviton though, so I may be missing a part of your question.

Edit: in QFT, there is a different picture, and the particles are the excitations of the field. Not the peaks, not the dents, but the vibration itself, or to use a broader term, the mode. I really like the picture given in this answer.

Mauro Giliberti
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    I believe the OP is referring to quantum field theory rather than the wave function of quantum mechanics – DavidH Jun 26 '20 at 20:37
  • Mh, I don't know. @FelipeReigosa if this is the case, tell me and I will delete this answer and post another one with a more fieldy explanation. – Mauro Giliberti Jun 26 '20 at 21:05
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    Yes DavidH is exacly right, but thanks for answering anyway. I look forward to your update then :) Do I use your name with a @ to call your attention to this comment like this @MauroGiliberti. Sorry, I'm new. – Felipe Reigosa Jun 26 '20 at 21:22
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    @MauroGiliberti - there's no picture in the link you provided. Did you link to the correct post, or has the picture perhaps been edited out? I only ask because I'd really like to see that picture! – ZenFox42 Jun 27 '20 at 12:17
  • @ZenFox42 I'm really sorry, I'm not a native speaker and I meant picture as in "an impression of something formed from a description"! I'm afraid I don't have an actual picture for this idea, sorry – Mauro Giliberti Jun 27 '20 at 12:37
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There is classical mechanics, classical electrodynamics, which are described with fields, which can be measured and mapped with voltmeters and various other instruments, and quantum mechanics fields which are described by differential operators and , as all quantum mechanics,depend on probability of detection, i.e. many observations made with the same boundary conditions.

Moreover, within each category (scalar, vector, tensor), a field can be either a classical field or a quantum field, depending on whether it is characterized by numbers or quantum operators respectively.

You say:

I'm just reading about how particles like the photon, electron, graviton, etc are each associated with their own fields.

There is quantum mechanics, and then there are the mathematical tools used to study the behavior of quantum mechanical systems.

The main tool for particle physics is Quantum Field Theory , which is a theory also used in other disciplines, as in condensed matter physics. So the "field" is a different representation, depending on the observations studied. Protons are not elementary particles, but composite, and a field describing them would belong to a model of nuclear field theory.

The photon and the electron are elementary particles, and the field theory describing their interactions is as follows.

All elementary particles in the table

elempart

are axiomatically assumed to be the building blocks of all matter (ignoring at the present gravity which is not definitively quantized yet) , this is the standard model of particle physics.

The quantum field theory (QFT) for these particles assumes that for each one of them ( and their antiparticles) there exists a field, an electron field, muon field etc..represented by the plane wave wavefunction of the corresponding solution of the quantum mechanical equation , Dirac equation for fermions, Klein Gordon for bosons, quantized Maxwell for photons. These wave functions cover all space time , a differential operators acting on them creates or annihilate a particle.

As plane waves cover uniformly all space, they cannot be used to describe real particles in the lab, as the single photons hitting a double slit,, one needs the mathematics of wave packets.. This reduces the probability space of seeing a particle in a trajectory.

The gravity field can have a dent in it like the one caused by a massive body or waves traveling through it, gravitational waves. Now is a electron for instance a dent or a wave in the electron field?

Lets forget gravity. The dent you are talking of is the wavepacket probability of representing a real electron track, in the bubble chamber for example

electrons

The two spiraling tracks in this bubble-chamber diagram were made by an electron and a positron. These particles were created by a high-energy gamma ray in a collision with the electron of a hydrogen atom in the bubble chamber. The long slightly curved downward track was made by the recoiling electron.

It will be a wavepacket represetnation with creation and annihilation operators forming the track of the particle, you may call it a dent on the all pervading electron field, BUT keep in mind that it is a mathematical model that describes observations well, currently.

When I started graduate school, there was no standard model table, and I was even taught a field theory with nucleons in nuclear physics. In the 1960's particle physics theory used Regge pole mathematics to explain the data. Then came the quark model, but it looks as if string theory may become the theory of the future, from which all others will emerge. One has to keep an open mind, for surprises in observations and in theory.

Edit 12/12/23 :The site for the pretty picture is out of action. Try the Cern site "do you want to see"

anna v
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  • Ok @anna, it would be so elegant if say an electron, was a dent, a peak on the electron field, with a corresponding dent in the EM field (since it has charge) and a corresponding dent in the gravitational field (since it has mass). That way moving a electron up and down would create waves in the EM field (photons) just like moving a mass would create waves in the gravitational field. What I'm understanding from your answer is that I'm mixing two uses of the "field", one an actual physical entity that can change (the gravitational field) and the other a mathematical tool only. – Felipe Reigosa Jun 27 '20 at 10:12
  • I will edit.:There are classical fields and quantum fields. – anna v Jun 27 '20 at 11:28
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    There will be changes in a classical field as the ones you expect, a charge going up and down with its classical fields creates the electromagnetic waves we call classical light described by Maxwell's equations. The gravitational field is classical too. – anna v Jun 27 '20 at 11:39
  • Oh I see. So is there a classical electron field? If so, we go back to my original post, what is a wave in the classical electron field, assuming the electron itself is a dent? – Felipe Reigosa Jun 27 '20 at 12:01
  • There is no classical electron. The electron by observation is aquantum mechanical entity. Look at the picture of the tracks I have provided. They cannot be explained with classical theories. – anna v Jun 27 '20 at 12:24
  • @annav Do you know what the 3rd particle is that originates from the same point as the electron and positron? It bends slightly in the same direction as the electron, thus it must be negatively charged. But since these particles seem to originate from a non-charged particle, how could we end up with a net charge? – Geert VS Dec 12 '23 at 01:15
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    @GeertVS the simplest explanation is that a gamma (photon is neutral) hit an electron and the photon turned into an e- e- pair. added CERN link to bubble chamber photos – anna v Dec 12 '23 at 04:55
  • @annav Thanks! But... why didn't we see the electron (or whatever charged particle it was) before? Shouldn't there be a path of this particle before the photon turned into an e- e+ pair? – Geert VS Dec 13 '23 at 21:58
  • @GeertVS .the electron is at rest, as far as the detection goes, it is around an atom of the medium on which the track is made, all tracks in the photo are made up of little electrons kicked a tiny bit out of the atoms by the charges passing them – anna v Dec 14 '23 at 05:04
  • @annav Thank you! – Geert VS Dec 14 '23 at 09:41