Yang-Mills Theory Explained: SU(N) Symmetry & Gauge Theory

[Qubix]

What exactly is a Yang-Mills Theory? Is it a general theory, based on SU(N) symmetry, which can then be applied for particular cases (ElectroWeak, Chromodynamics) ? Is it like a general mathematical model of gauge theory ?

 

[jedishrfu]

What exactly is a Yang-Mills Theory? Is it a general theory, based on SU(N) symmetry, which can then be applied for particular cases (ElectroWeak, Chromodynamics) ? Is it like a general mathematical model of gauge theory ?

Yes its a gauge theory:

http://en.wikipedia.org/wiki/Yang-Mills_theory

 

[karlzr]

Not necessarily SU(N). It can also be like SO(N), Sp(N), etc. The idea is we need to introduce gauge fields to keep the theory gauge invariant.

 

[dextercioby]

The gauge group of the field theory needs to be nonabelian, else it would just be quantum electrodynamics.