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a reply to: dragonridr

You are talking about electrons in atoms and multiple electrons, you are also talking about the separate electric force and magnetic force.

I am not talking about an atom. I am talking about 1 electron, in free space. Being accelerated once. To produce one unit of EM radiation. You see I am using the baseness, the most simple and fundamental expression of quanta and field, to comprehend the most fundamental aspects of the most fundamental constituents, how they exist, function and relate, if even in a general way. If electrons exist, and can exist outside of atoms, and are responsible for producing EM radiation when accelerated, lets not talk about atoms, lets talk about a single electron, because that is what I am asking about and want to know about.

What is your reasoning, as to why when 1 electron is accelerated once to produce one unit of EM radiation; EM radiation, as is the waving of the EM field, does not propagate as an expanding circle surrounding the electron, expanding in the direction perpendicular to the direction of the electrons acceleration.

originally posted by: ImaFungi
a reply to: dragonridr

You are talking about electrons in atoms and multiple electrons, you are also talking about the separate electric force and magnetic force.

I am not talking about an atom. I am talking about 1 electron. Being accelerated once. To produce one unit of EM radiation.

What is your reasoning, as to why when 1 electron is accelerated once to produce one unit of EM radiation; EM radiation, as is the waving of the EM field, does not propagate as an expanding circle surrounding the electron, expanding in the direction perpendicular to the direction of the electrons acceleration.

Doesnt matter if its a single electron or multiple in an atom process is still the same. any electron by its very nature creates an electric field as long as that electron is in motion. Now we can stop it for example super cooling it than nothing happens.

originally posted by: dragonridr

originally posted by: ImaFungi
a reply to: dragonridr

You are talking about electrons in atoms and multiple electrons, you are also talking about the separate electric force and magnetic force.

I am not talking about an atom. I am talking about 1 electron. Being accelerated once. To produce one unit of EM radiation.

What is your reasoning, as to why when 1 electron is accelerated once to produce one unit of EM radiation; EM radiation, as is the waving of the EM field, does not propagate as an expanding circle surrounding the electron, expanding in the direction perpendicular to the direction of the electrons acceleration.

Doesnt matter if its a single electron or multiple in an atom process is still the same. any electron by its very nature creates an electric field as long as that electron is in motion. Now we can stop it for example super cooling it than nothing happens.

Even theoretically if it was not in motion, there would still exist electric and magnetic field right, as the magnetic moment inherent in a charged particle, and the nature of charged particle signifying electric charge, and the existence of EM field, that is coupled to electron/charge particle that gives it the potential to have these natures?

originally posted by: ImaFungi

originally posted by: dragonridr

originally posted by: ImaFungi
a reply to: dragonridr

You are talking about electrons in atoms and multiple electrons, you are also talking about the separate electric force and magnetic force.

I am not talking about an atom. I am talking about 1 electron. Being accelerated once. To produce one unit of EM radiation.

What is your reasoning, as to why when 1 electron is accelerated once to produce one unit of EM radiation; EM radiation, as is the waving of the EM field, does not propagate as an expanding circle surrounding the electron, expanding in the direction perpendicular to the direction of the electrons acceleration.

Doesnt matter if its a single electron or multiple in an atom process is still the same. any electron by its very nature creates an electric field as long as that electron is in motion. Now we can stop it for example super cooling it than nothing happens.

Even theoretically if it was not in motion, there would still exist electric and magnetic field right, as the magnetic moment inherent in a charged particle, and the nature of charged particle signifying electric charge, and the existence of EM field, that is coupled to electron/charge particle that gives it the potential to have these natures?

It would have an electric field but no magnetic field motion of the electron is required. the motion of an electric field creates a magnetic field. Think of a wire it produces a magnetic field because electrons are in motion.

originally posted by: dragonridr

originally posted by: ImaFungi

originally posted by: dragonridr

originally posted by: ImaFungi
a reply to: dragonridr

You are talking about electrons in atoms and multiple electrons, you are also talking about the separate electric force and magnetic force.

I am not talking about an atom. I am talking about 1 electron. Being accelerated once. To produce one unit of EM radiation.

What is your reasoning, as to why when 1 electron is accelerated once to produce one unit of EM radiation; EM radiation, as is the waving of the EM field, does not propagate as an expanding circle surrounding the electron, expanding in the direction perpendicular to the direction of the electrons acceleration.

Doesnt matter if its a single electron or multiple in an atom process is still the same. any electron by its very nature creates an electric field as long as that electron is in motion. Now we can stop it for example super cooling it than nothing happens.

Even theoretically if it was not in motion, there would still exist electric and magnetic field right, as the magnetic moment inherent in a charged particle, and the nature of charged particle signifying electric charge, and the existence of EM field, that is coupled to electron/charge particle that gives it the potential to have these natures?

It would have an electric field but no magnetic field motion of the electron is required. the motion of an electric field creates a magnetic field. Think of a wire it produces a magnetic field because electrons are in motion.

So I suppose the expression that electron has an intrinsic magnetic moment is assuming always a moving electron? Even still, Does the electro magnetic field exist surrounding a theoretical stationary electron? Does it have a >0 value? The field must exist as an independent potential, in order for 'affect' at a distance, force, to occur only by the electrons movement.

A stationary electron, you say there is just some electric field surrounding it, and than move the electron a bit, and out of no where magnetic field appears too?

Its not that, a stationary electron exists, and Electromagnetic field is coupled to it, and all other electrons in space? So that when an electron moves, it moves the field, which moves electrons at a distance?

Well you are right in that the source in my experiment was a semiconductor, and if you look deeper into the physics of it, would produce more than a single photon. HOWEVER the mode of operation produces a small number of photons. The source was calibrated such that each time it 'flashed' it produced an average of 0.25 photons, with a poissonian distribution.

What this means is that most of the times you pulse the device it doesn't produce any light. We have a small detector device which cuts out the acceptance of the system also. So basically we sit and watch the device for single photon detection. The detector can be moved around multiple detectors can be placed around the setup (which there were looking for reflections)

The way the device works is that the light is typically produced in the drift direction of the electrons, thus it tends to be in a forward cone.

Now single electrons in 'free' space. This is a little rarer. It requires a quadrupole trap in which you can place a single ion or an electron and have it wobble around in free space. The issue is always quality of vacuum and purity. something that is extremely difficult to produce.

However single electrons or not, evidence we see from bunches of electrons do not support the spherical growth as you suggest. There is always momentum transfer and what you suggest is basically a momentum's transfer behavour in which you expect to have random emission, basically that each photon that comes out of a stationery source will do so in random directions, it is still however a single photon, moving in ONE direction, not a spherical shell like construct.. As soon as any net momentum the photons will tend to come in the direction of that momentum (if the momentum is large enough)

There is no evidence for this shell like expansion which you propose, not even in Cyclotron or Cherenkov emission... which you might see as the biggest evidence

originally posted by: ErosA433
each photon that comes out of a stationery source will do so in random directions, it is still however a single photon, moving in ONE direction, not a spherical shell like construct..

Correct, a single photon moves in a direction, it doesn't expand.

There is no evidence for this shell like expansion which you propose, not even in Cyclotron or Cherenkov emission... which you might see as the biggest evidence

Correct again, if you mean for a photon which is the implied meaning I assumed.

The other assumption I made is that ImaFungi took a model from classical electromagnetism, which describes the behaviors of large groups of electrons (and thus large groups of photons), and then tried to infer that this classical model applies to a single photon, but it doesn't. The classical model however can look somewhat like a circle, or in this case, a torus, but this is many photons all going in different directions, not a single photon:

Dipole antenna

Three-dimensional view of the far-field radiation pattern of the half-wave antenna.

originally posted by: ImaFungi
My explanation is correct of course.

Well if you think your explanation is correct and all mainstream physicists are wrong, I'm not sure why you're asking questions here because the answers here are experimentally verified by mainstream physics, not something someone made up because they think it makes sense.

Classically nature works much the way we might expect, but not so in quantum mechanics. I'll leave you with this to ponder, from Richard Feynman's book "QED, the strange theory of light and matter", p10:


You should probably read that many times and let it sink in. But from what you've said, you still think nature can be explained classically.

originally posted by: ImaFungi
There is nothing strange about this, purely classical. One photon, one baseball, runs into a material, it must go one way or another.

No it's not classical at all, and Richard Feynman explains this at length in his New Zealand Lecture on video, how classical theorists struggled to explain things like partial reflections in glass, and didn't come up with a successful theory that could explain all aspects of it. Moreover, a single marble has not been shown to cancel itself out or make itself disappear, as in the end result of that experiment.

You can live in a fantasy world that doesn't agree with experiment, and everything is logical, or, you can come down to reality, meaning real experiments, that show nature's behavior is not always what we consider logical.

a reply to: Arbitrageur

Why don't they spell "physics" phonetically?

originally posted by: chr0naut
a reply to: Arbitrageur

Why don't they spell "physics" phonetically?

Because its a greek word. Side note it was named by Aristotle so physics has been around for a long time.

originally posted by: ErosA433

Now single electrons in 'free' space. This is a little rarer. It requires a quadrupole trap in which you can place a single ion or an electron and have it wobble around in free space. The issue is always quality of vacuum and purity. something that is extremely difficult to produce.

However single electrons or not, evidence we see from bunches of electrons do not support the spherical growth as you suggest. There is always momentum transfer and what you suggest is basically a momentum's transfer behavour in which you expect to have random emission, basically that each photon that comes out of a stationery source will do so in random directions, it is still however a single photon, moving in ONE direction, not a spherical shell like construct.. As soon as any net momentum the photons will tend to come in the direction of that momentum (if the momentum is large enough)

So, theory of the electron. Theory of EM field which surrounds the electron. Theory of how exactly the EM field is coupled to the electron.

It is difficult to discuss this (because of the difficulty of knowledge and comprehension of those above items, but also) because an electron in free space which is coupled to the EM field, we would imagine this electron to either be moving at a constant speed, or even though I feel it may be impossible, therefore might not be worth to use for though experiment and discussing fundamental theory, stationary. I am suggesting speaking of a single electron far away from all matter, in free space to avoid having to think about how all near matter may influence this electron, I strictly am concerned with how an electron exists, how it is coupled to the EM field, and how it is stated with confidence, that 'when an electron is accelerated, the EM field which it is coupled to it reacts in such a way as can be called particle or wave'.

The reason I started to say it is difficult, is because a single electron in free space, lets say moving at an 'an object will remain in motion unless....' velocity, I know it is perhaps an inconclusive argument whether or not an electron moving at a constant speed is constantly causing EM radiation, but if it is or if it is not, I believe both can fit into my current comprehension of what might be occurring.

For starters, lets say an electron traveling at a constant speed, is not constantly disturbing the EM field that immediately is surrounding it, constantly causing EM radiation.

So to get back to what I began say, the reason it is difficult is, to accelerate this electron in free space, to think about how the EM field which is coupled to it might react, to the electrons acceleration, we will have to introduce, at the very least 'something' into the local field of the electron, be a charged particle itself, or the EM radiation resulting from the acceleration of another charged particle. Which from my standpoint of concern and ignorance, the latter would be an infinite regress, as I am trying to get to the bottom of what EM radiation might fundamentally be and exist as, and if that is the only means I have to use, to accelerate the electron, to find out how EM radiation might fundamentally be and exist as, well than thats a big problem.

So maybe it might be easier to use another electron that approaches, though there still it may be argued the electron will never touch, it undeniably will produce a local field to local field effect on our single test electron, before they actually marbles-like collide. So, well that seems like another problem.

But lets say the electron we want to use to accelerate our single electron in free space, can actually get quite close enough to touch, the general idea regardless of how it is done is that the single electron in free space, will have its momentum altered, and the repercussions this will have on the local field which is attached to it.

So if we imagine an electron like a point (is that fair?) how ought we imagine it is attached to the EM field?

First we will need to have an argument on how many dimensions an electron exists in, are you one of those that believe 2 (or I suppose 3rd is time in that case)?

And then your view of the EM field, is lines drawn in all directions from this 2d dot?

To most approximate reality, would there be approaching infinite lines, to the point of almost the entire area being shaded surrounding an electron and that is how the field exists?

Or, would there be a surprisingly limited number of lines, which in reality would correlate to?

If the electron was 3d which I believe, if it is an object that exists in reality, it must be, would the lines be draw all around it extending in all directions? And an approaching infinite number, or a very limited number?

Well this picture automatically draws interesting visions of this electron moving through space, and how the EM field might react to it moving in space.

But can we not see that when the electron is disturbed, accelerated, however that may be, it would be uncontrollable, and undeniable, that because it is coupled to the EM field, which surrounds it, all points of the EM field which is coupled to the electron, would react, to the force of the electrons acceleration?

How could the electrons direction and/or velocity be altered, without altering the EM field that surrounds the electron?

Or as you believe, how could the electrons direction and/or velocity be altered, and result in only the reaction of an infinitesimal, or what would be equivalent to 1 field line, being disturbed?

Before I go any further, I will await to see how you respond to those questions I have offered, to first establish an agreeable template or foundation, for this topic of discussion.

a reply to: ImaFungi

Ok this is starting to get complicated because there is something i dont think your aware of. Do you know there are 3 kinds of waves you have to deal with in your scenario? You have matter wave is represented by de-Broglie relation(particle-wave duality), EM wave is represented by Maxwell's equations(electromagnetic form of energy), and finally Schrodinger's equation wave is interpreted by Born as its absolute square represents probability of finding the system in some region of space. This is part of the problem you have to understand energy and its forms it can take. An incomplete understanding and you end up spinning circles and thinking there is some field everywhere in space. There isnt fields are created they are not preexisting.

a reply to: ImaFungi

I think much of this post doesn't make concise sense. You pose many many assumptions and ask questions that are either not questions, or at questions at the end of elaborate thought experiments.

You say you are interested in what exists in reality and yet at the same time you are wanting to describe something fundamental without even looking at or considering what we know already as a means to that end.

originally posted by: dragonridr
An incomplete understanding and you end up spinning circles and thinking there is some field everywhere in space. There isnt fields are created they are not preexisting.

Can you reconcile that with this quote from Freeman Dyson who doesn't say there is "some field" everywhere, he says there are "ten or twenty" of them? I bolded that comment below:

Freeman Dyson on how to imagine quantum fields

It is not possible to explain in nontechnical language how particles arise mathematically out of the fluctuations of a field. It cannot be understood by thinking about a turbulent liquid or any other classical model. All I can say is that it happens. And it is the basic reason for believing that the concept of a quantum field is a valid concept and will survive any changes that may later be made in the details of the theory.

The picture of the world that we have finally reached is the following. Some ten or twenty different quantum fields exist. Each fills the whole of space and has its own particular properties. There is nothing else except these fields; the whole of the material universe is built of them. Between various pairs of fields there are various kinds of interaction. Each field manifests itself as a type of elementary particle. The number of particles of a given type is not fixed, for particles are constantly being created or annihilated or transmuted into one another.

...Even to a hardened theoretical physicist, it remains perpetually astonishing that our solid world of trees and stones can be built of quantum fields and nothing else. The quantum field seems far too fluid and insubstantial to be the basic stuff of the universe.

Yet we have learned gradually to accept the fact that the laws of quantum mechanics impose their own peculiar rigidity upon the fields they govern, a rigidity which is alien to our intuitive conceptions but which nonetheless effectively holds the earth in place.

a reply to: Arbitrageur


This involves string theory an imbalance was created causing a symmetry imbalance at the cteation of the universe. I for one am not a fan of string theory it may turn out to be correct but even there an imbalance creates the fields the fields interact to create matter. Fields still need something to create them but once created they will expand.

As for string theory im by no means a string theorist but if were lucky one may stop in to discuss this. Me personally i think energy created matter and not so much eave interactions.

A photon is both created and destroyed at the same moment. I understand that time dilation gives it a lifetime. When a photon is created, is it a discreet packet of energy? Since light is a wave also, if the source of the light is turned off, the wave should cease to exist since there is no source to push or add energy to the wave to keep it moving.

Does light energy, after it has been emitted cease to exist after the source has been turned off? Has it been proven through experimentation that emitted light energy continues on after its energy source no longer exists?

originally posted by: eManym
A photon is both created and destroyed at the same moment. I understand that time dilation gives it a lifetime. When a photon is created, is it a discreet packet of energy? Since light is a wave also, if the source of the light is turned off, the wave should cease to exist since there is no source to push or add energy to the wave to keep it moving.

Does light energy, after it has been emitted cease to exist after the source has been turned off? Has it been proven through experimentation that emitted light energy continues on after its energy source no longer exists?

No stars we observe in other galaxies no longer exist. A photon needs to be created but once created is perfectly happy going it on its own.

originally posted by: dragonridr
This involves string theory an imbalance was created causing a symmetry imbalance at the cteation of the universe.

It's not clear that string theory is involved, but he does mention "The quantum field" so that makes it clear that he's talking about Quantum Field Theory. I don't think he's talking about string theory.

It has been suggested that Quantum field theory may the low energy version of string theory, but I think it stands on its own without string theory even if this is not the case:

Quantum field theory of the fundamental forces itself has been postulated to be the low-energy effective field theory limit of a more fundamental theory such as superstring theory.

So, some think they could be related, but they aren't the same thing.

originally posted by: eManym
A photon is both created and destroyed at the same moment.

From the photons' perspective perhaps, but since you're not a photon, that shouldn't be, and isn't, your perspective. Time is relative.

When a photon is created, is it a discreet packet of energy?

Yes

Since light is a wave also, if the source of the light is turned off, the wave should cease to exist since there is no source to push or add energy to the wave to keep it moving. Does light energy, after it has been emitted cease to exist after the source has been turned off? Has it been proven through experimentation that emitted light energy continues on after its energy source no longer exists?

See Dragonridr's correct answer.

originally posted by: eManym

When a photon is created, is it a discreet packet of energy? Since light is a wave also, if the source of the light is turned off, the wave should cease to exist since there is no source to push or add energy to the wave to keep it moving.

Does light energy, after it has been emitted cease to exist after the source has been turned off? Has it been proven through experimentation that emitted light energy continues on after its energy source no longer exists?

In any wave phenomena that I can immediately think of, the source isn't "pushing" or "adding energy" to the waves that have already left the source. Waves propagate because that's what waves tend to do.

As a sort-of example, consider lightning. Once the strike causes air expansion along the channel, creating a thunder clap, the event is over. Yet, miles away, you will hear the boom. The lightning has long gone. But the shock wave will go on propagating outward until the energy is so low it falls below thermal noise.

For EM, wave propagation away from the point of creation depends on a multitude of things. For light, it's difficult to see that because the wavelength of visible light is so short. But there's a region around the source where magnetic and electric fields are tangled in a way that's difficult to model exactly, called the near field region. If you're talking light, what you get in the near field is called an evanescent wave, and it's got odd properties. Outside a one-lambda volume around the emitter, you have a propagating wave, and it's no longer attached in any way to the source.

The same happens with radio, but since radio is a longer wavelength of EM, you can often directly observe a distinct difference in what's going on in the near field and the far field. In the near field, if your source isn't properly balanced, you can get lots of h field and not enough e field, or vice versa. In which case, the h and e fields won't couple well, and a lot of the signal will just pile up in the near field and NOT radiate. But once that wave's past about a lambda it, too, is no longer coupled to the antenna and goes its merry way no matter what happens to the source.

Within the near field, you could almost visualize it as you state - the source is "pushing it", or at least it's still coupled to it. It's not a proper EM wave yet. So, if I siphon off some of the energy, it will reflect in less power in the far field, everywhere. If you do that in the far field, it won't have any effect on the wave elsewhere. But in the near field, it does.

An EM example you might be familiar with is radar. You emit a short burst of EM, then stop. And you wait, and listen for the reflections of the outgoing emission to come back.

Heck, some of the quirkier digital stuff I've worked with puts multiple symbols on the transmission line at the same time. They run down the PCB trace like little soldiers marching in formation. Sometimes you might have two or three states running down the trace at one instant.

a reply to: Arbitrageur


In formal QFT scaler fields explain the interactions bit are still created there are some variants that say multiple fields can simulate matter for example. But that goes back into string theory. The line becomes blurred string theorists will often use QFT. They basic interactions arent enough for string theory and they will use more complicated multi-component systems of interacting Fermi and Bose fields. For example chiral field takes in to account certain homogeneous spaces that are not necessarily linear like a sphere the gauge fields are connections in certain vector bundles, these are related to the electromagnetic field, the gravitational field and the Yang–Mills field.er they still havnt made the link between QFT and string but they are trying.

Realize all interactions in QFT are seen as a scalar field, a vector field, a spinor field or a tensor field according to whether the value of the field at each point is a scalar, a vector, a spinor or a tensor. This explains the interactions of all particles but they again are not preexisting and need to be created. Now these fields thse fields can be thought of as extending throughout the whole of space. In practice, the strength of most fields has been found to diminish with distance to the point of being undetectable. But the key here is you can never truly have a zero value so if there was only one star in the entire universe no matter how far you move from it you still never get a zero value. Just like that old saying if you keep halving the distance between you and your destination youll never reach it.

originally posted by: Bedlam
As a sort-of example, consider lightning. Once the strike causes air expansion along the channel, creating a thunder clap, the event is over. Yet, miles away, you will hear the boom.

Great point. This made me think of the more dramatic example of the 2004 Earthquake which lasted about 10 minutes, but after that stopped, the tsunami wave kept propagating for at least 7 hours to distant shores.

a reply to: dragonridr
I found this quote from Dyson that pretty much confirms he's never worked on string theory:

www.math.columbia.edu...

I would like to say a few words about string theory. Few words, because I know very little about string theory. I never took the trouble to learn the subject or to work on it myself.