Landau theory
a theory that Lev Landau introduced in an attempt to formulate a general theory of continuous (i.e., second-order) phase transitions
en-US/ˈlænˌdaʊ ˌθiəˌɹi/
en-GB/ˈlændaʊ θɪəɹiː/
a theory that Lev Landau introduced in an attempt to formulate a general theory of continuous (i.e., second-order) phase transitions