Wave/particle duality - electrons and photons

[namewills]

I understand that:

1. Electrons can interact with each other in both particle-like and wave-like ways (eg. can exhibit wavelike interference in double slit experiment)

2. Photons can interact with each other in both particle-like and wave-like ways

3. Electrons and photons can interact with each other in a particle-like way (eg. Compton Effect)

Is there every a scenario in which electrons and photons interact with each other as waves?

 

[lightarrow]

It depends on what you define as "interaction". In your post you made a mixing of concepts, so in your sense photons could "interact" as waves with electrons: you shine light on electrons and then you collect the scattered/reflected light. Example: light reflection by a metal surface (but it would be something analogous with a bunch of free electrons).

 

[namewills]

In your example, the photons are "interacting" as waves, but aren't the electrons still behaving like particles? I'm wondering if they can interact with each other in such a way that they're both exhibiting wave-like properties/behaviours within that interaction. Maybe I'm not phrasing this question very well...

 

[lightarrow]

Actually you don't even need to talk about particles when you consider the process of light reflection off a metal surface, you can use just Maxwell's equations (classical physics).

 

[Calrik]

It always depends on how you describe the system and measure it in QM, if you describe it as a particle system it will show different results than if you describe it as a wave. That at essence is QM.

That said as said above is pretty much it.

Everything can interact in every way we can describe it, but only some ways will be indicative of a solution that makes sense.

 

[Delta2]

When we speak of photon as wave as i understand it we refer to the classical EM wave with the same frequency as photon's.

Isnt this some sort of cheating to fallback to classical physics to explain wave nature of photon?

Isnt there some other way like for example to refer to photon's wave function?

 

[soothsayer]

Well sure, if you do the double slit experiment with some device that shoots photons and electrons, you'd see the same ol' interference pattern.

 

[lightarrow]

When we speak of photon as wave as i understand it we refer to the classical EM wave with the same frequency as photon's.

Isnt this some sort of cheating to fallback to classical physics to explain wave nature of photon?

Isnt there some other way like for example to refer to photon's wave function?

They say a photon's wavefunction doesn't exist or is very difficult to define, since there isn't (or is very difficult to define) a position operator for a photon.

 

[Calrik]

They say a photon's wavefunction doesn't exist or is very difficult to define, since there isn't (or is very difficult to define) a position operator for a photon.

Quite, but that doesn't make it impossible to be defined.

 

[joppon]

What is a particle?

 

[Calrik]

What is a particle?

Good question let's see if our honourable gentlemen can answer it because I can't well except to give the usual trite answer. :D

 

[Delta2]

What is a particle?

Probably someone with a PhD will have to give a satisfying answer but i ll give my own thought:

Particle is the building block of physical reality. Its two most important properties (if we can call them this way) are mass and energy. Both mass and energy are terms that express the various interactions of the particle with itself, other particles and spacetime.

So normally i should proceed with what is physical reality, what is spacetime and what exactly are those interactions. But i won't it really makes me dizzy to try to explain those, falling in self loop definitions (defining something with itself) and inconsistencies. However one idea that i really like and is mentioned in an introductory text to loop quantum gravity is that spacetime is not a passive (as seen in classical physics) or a dynamic (as seen in relativity) entity(=background where other things happen) but it consists (not contains) of other particles.

 

[lightarrow]

According to Wigner's criterion, each type of elementary particle corresponds to an irreducible Hilbert space representation of the restricted Poincare group.
But don't ask me to explain it...
(Not for this year, however )