Gibbs state

A Gibbs state, also known as a Gibbs measure or thermal state, is a specific type of probabilistic representation of a system in statistical mechanics that describes the distribution of microstates at thermal equilibrium. It arises from the principles of statistical mechanics and is named after Josiah Willard Gibbs. The Gibbs state is characterized by its dependence on temperature and the energy of the system. It is particularly relevant for systems in contact with a heat bath at a fixed temperature.