Phonons _ Guage Bosons

1. Dec 25, 2008

nuby

Whats the difference between phonons and guage bosons?

2. Dec 25, 2008

olgranpappy

In classical field theory the Lagrangian of interest (which basically defines what "theory" I'm talking about) may have a symmetry. For example, it may happen that my Lagrangian doesn't change if I multiply the fields by a phase $e^{i\phi}$. If I let $\phi$ depend on space and time (this is called "gauging") then the multiplication of the fields by $e^{i\phi(x)}$ no longer leaves the Lagrangian invariant. But, by introducing *more* fields called gauge fields (i.e., by changing the Lagrangian I start with, changing the theory), I can force the Lagrangian to be invariant. When I quantize the gauge fields, the resulting particles are called "gauge bosons".

When I quantize the theory of lattice vibrations, I end of with particles (which are bosons) called "phonons".