# 3D model of light

1. Nov 13, 2004

### mat337d

Light
In this link the auther describes the electron as a pump for light. He describes the 3D version of light to be a corkscrew shape.
Is this true at all?
It has really helped me visulize the atom and light better.
For this model to work wouldnt this require ether (that does not exist).
thanks

2. Nov 14, 2004

### mat337d

no one has an opinon on this.

3. Nov 15, 2004

### T.Roc

mat337d,

Science has no model of the photon. Therefore, there are many ideas floating around to try to understand WHY photons do what they do.

I think that it does move in a spiral. When you combine spin, angular momentum, and forward (efficient) movement, with a symmetrical oscillation (wave form), it is the only logical conclusion. A circle with the link broken to accommodate forward motion, and the leading diameter to accommodate smaller wavelengths.

TRoc

4. Nov 15, 2004

### ZapperZ

Staff Emeritus
You need to be VERY careful when you say something like this. It leaves the impression that we don't know anything about photons and how to generate exotic forms of it. This is FALSE.

I urge anyone with such opinion to go visit a synchrotron research center, which is scattered all over the world. See how they generate plane polarized and circularly polarized light sources using various insertion devices that are then used to study a number of other things, from the properties of materials to medical drugs, to protein/DNA crystallogrophy, etc. In other words, we know so much about the properties of these photons that we can USE it to study other things with them. Now I don't know about you, but when we use something to study the properties of others, it is a sure sign that we know a whole lot about that "something".

Zz.

5. Nov 15, 2004

### Laser Jock

I'm not sure I like his/her corkscrew analogy. First, their description of radiation from an electron returning to the ground state is over simplified. They imply that the electron has physically changed its location when it goes to the ground state. This is not necessarily true. The electron changes energy states, and now it is more likely to be found near the nucleus, but the location of the electron immediately after the transition may be the same as it was immediately before. The error lies in thinking of electrons orbiting around the nucleus as planets orbiting around the sun. A real atom is not like that.

Second, the electro-magnetic fields of light only look like a corkscrew if the light is circularly polarized (has angular momentum). A beam of light with orbital angular momentum can also look like a corkscrew. But in general, I would say that the corkscrew picture is misleading.

I don't like this paragraph and I really don't like that last sentence. I think that it is deeply misleading. It implies that a photon is a single cycle or half-cycle of an E-M wave. That is absolutely not true.

[Edit for spelling]

Last edited: Nov 15, 2004
6. Nov 15, 2004

### CharlesP

I have a keen interest in this subject because I always wanted to know the size and shape of a single photon. I am familar with the equations for plane waves and waves radiated by transmitting antennas, but individual photons leave me lost.

7. Nov 16, 2004

### Laser Jock

You are in good company then. Photons are confusing. Asking what the size and shape of a photon is somewhat meaningless since it is a quantum mechanical "entity". You can describe a wave function which can be more or less localized, but it is a mistake to try to think of it as classical particle with a well defined size and shape.

8. Nov 17, 2004

### ObsessiveMathsFreak

I'm not sure if this is really what your asking, but I'll say it anyway.
EM waves are usually represented by perpendicular electric and magnetic fields $$\mathbf{E}$$ and $$\mathbf{B}$$ respectively. $$\mathbf{E}$$ and $$\mathbf{B}$$ are usually sinusoids. It is usual for each of these fields to exist in one plane only. i.e.
$$\mathbf{E} = (E(x,t),0,0)$$ , $$\mathbf{B} = (0,B(x,t),0)$$

However there's nothing stopping you from making $$\mathbf{E} = \mathbf{E_0} (Cos(x-ct),Sin(x-ct),0)$$ and solving for $$\mathbf{B}$$. Hmmm... I'm not too sure about that form of $$\mathbf{E}$$, but a "rotating" solution of $$\mathbf{E}$$ and $$\mathbf{B}$$ is possible, where the field are always perpendicular, but they both spin around instead of just increasing and decreasing. Perhaps this is the corkscrew effect you mentioned?

9. Nov 17, 2004

### rayjohn01

To all, Yes they are confusing -- in the theory of interference it is reasoned that only one photon can interfere with itself this is because incoherent emission would destroy interference patterns by more than one photon interfering with each other. In the Michelson Morley experiments on light there was a direct,implication that photons were at least 2 meters in length ( the coherence length of the apparatus ) , but it is worse than this -- in a LARGE telescope the circle of confusion is determined by the mirror diameter which maybe many meters and as far as I know has no limit .
This is a little talked about subject but if you take radio telescopes planted at huge distances but linked -- it suggests that photons are of infinite length until actually absorbed by something ( an atom ).
Someone said that the photon is the key to the universe -- well it's certainly one of them. Ray

10. Nov 18, 2004

### Vern

I've explored that concept and such descriptions seem possible to me.

11. Nov 18, 2004

### mat337d

"How can something be both a particle and a wave at the same time? For one thing, it is incorrect to think of light as a stream of particles moving up and down in a wavelike manner. Actually, light and matter exist as particles; what behaves like a wave is the probability of where that particle will be. The reason light sometimes appears to act as a wave is because we are noticing the accumulation of many of the light particles distributed over the probabilities of where each particle could be."

I read this off of a quantum mechanics web site it is quite interesting. I never thought the wave was a probability distribution of photons.

quantum

12. Apr 11, 2005

### juanito

If light passed through a slit I imagine it would be in the shape of a wave. If I turned the slit one degree clockwise or counterclockwise, it would still be in the shape of a wave wouldn't it? And if I continued turning it and somehow observed it (oscilloscope possibly?) over and over again, I would still "see" it as a wave I assume. So wouldn't this mean that the 3D shape of a wave could be described as tubular with constrictions at wavelength intervals?