Critical exponent

Summary

A critical exponent is the power in the power law that a physical quantity follows near a critical point. The standard exponents $\alpha, \beta, \gamma, \delta, \nu, \eta$ describe the specific heat, the order parameter, the susceptibility, the critical isotherm, the correlation length and the decay of correlations. They are the same for all systems of one universality class. They obey scaling relations, so only two of them are independent in most cases.