Does a photon carry a magnetic field?

[davenn]

Before you bring Feynman into a discussion I think you should make sure that you understand just what he did say and didn't say. The 'squiggle' on a Feynman diagram in no way tells us that a particle goes from place to place, for example - can you find any evidence of his actually saying that it does?

There are a million miles between the separate ideas of quanta and particles.

you go me watching his lecture again, I think the 3rd time now :)

He catagorically states "light is particles NOT waves". and shows how experiment demonstrated that using a PM tube. "waves can explain many things, but not light, light is particles"

http://vega.org.uk/video/programme/45"

specifically, if you don't want to sit through the whole lecture... 36mins in and 48mins in


just stirring you up with the... heresy heresy I cry comment ;) but since you asked for a reference from him, I gave it :)

I am NO physicist, just a basic understanding of some things. you could baffle me with maths in an instant. But I will put my trust, on this subject, in some one with a Nobel Prize ;)

cheers
Dave

 

[Born2bwire]

you go me watching his lecture again, I think the 3rd time now :)

He catagorically states "light is particles NOT waves". and shows how experiment demonstrated that using a PM tube. "waves can explain many things, but not light, light is particles"

http://vega.org.uk/video/programme/45"

specifically, if you don't want to sit through the whole lecture... 36mins in and 48mins in


just stirring you up with the... heresy heresy I cry comment ;) but since you asked for a reference from him, I gave it :)

I am NO physicist, just a basic understanding of some things. you could baffle me with maths in an instant. But I will put my trust, on this subject, in some one with a Nobel Prize ;)

cheers
Dave

But again, the qualifier in the quote that you contested was that classically, light is waves and this is unequivocal in my opinion. The particle behavior of light does not arise unless you go to quantum electrodynamics (although we can certainly see particle behavior using classical experiments but classical theory fails to account for it). But I would even caution against labelling it as a corpuscle as that carries a very classical definition. The quantum field theory particle is not truly corpuscular, it is an amalgamation of what we classically think of as a wave and a particle.

 

[sophiecentaur]

. . . . But I would even caution against labelling it as a corpuscle as that carries a very classical definition. The quantum field theory particle is not truly corpuscular, it is an amalgamation of what we classically think of as a wave and a particle.

Yes. The problem with trying to think in terms of particles in the conventional sense is that they have to have zero extent, for a start. I say that because, would not their 'size' relate, in some way to their wavelength? This would lead to the lowest energy photons (the 'biggest' ) being the size of a mountain or a house, if you extend the implied size of light photons so that seems a non-starter for a good model. So how would these infinitely small particles be expected to interact with the structures they encounter as they would mostly be encountering empty space (analogous to the results of Rutherford scattering)?
To explain how they actually could interact, you'd have to give them some field around them so why not stick with the EM wave to explain it all. The Quantisation aspect need only refer to the energy needed for an interaction to occur and needn't involve these little bullets - except as a useful shorthand, which I agree is useful.