Understanding Phonons - Making Sense of Virtual Particles

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DaveC426913
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I'm making my way through 'The Trouble with Physics' and am getting my head around phonons.

It sounds to me like
- phonons are a sort of virtual particle that results from emergent properties of the underlying forces
- (IMHO) photons-as-particles could be considered phonons resulting from the underlying electromagnetic wave (thus the dual nature of light)
- (IMHO) the current flow in a wire in the positive direction (i.e. opposite the movement of electrons) is actually a moving "electron hole", and this moving positive charge can be considered as a (positively-charged) phonon particle.

Am I barking mad?
 
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I always thought that phonons where just a quantumized form of vibrations in matter. In other words, packets of vibrations, just like photons can be thought of as packets of EM waves.
 
Ah. OK, so it's limited to sound-like propogation. That does gel with what the book was saying, I was over-enthusiastic.
 
More precisely: sound-like propagation is only a particular kind. Phonons are linkened to vibrations but these can be acustical or optical. You find difference in a bi-atomic chain in which vibrations take place in-phase or out of phase. Modes can be longitudinal or transverse. Phonons are optical with an interaction with em field occurs.
 
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