PHZ3400 Symmetry Breaking

Ferromagnet and Curie-Weiss Theory

>>Insert Brief overview of ferromagnetism here?

The relationship between magnetic susceptibility versus temperature is linked through the Curie temperature of the material. Combining equations of Curie's Law and magnetic susceptibility, the Curie-Weiss law is formed.

$\chi ={\frac {C}{T-T_{c}}}$

The denominator can become undefined, which is alarming. In nature, this represents spontaneous magnetization when T = T_c or below.

Caution must be taken near the critical point, in this case Curie Point. The mean field approximation does not accurately represent critical behavior nearby the critical point.

Other Examples of Symmetry Breaking

Explicit Symmetry Breaking

     Explicit symmetry breaking happens when the actual laws of the system are  not invariant for the symmetry in question. 

Dynamical Symmetry Breaking (special form of spontaneous symmetry breaking)

    (summary here-Fermion condensates)

Chiral Symmetry Breaking