Thermal Green Functions at Zero Energy
نویسنده
چکیده
The thermal expectation values of all possible bosonic generalised retarded functions evaluated at zero energy are studied. The relationship of such functions to calculational schemes, technical problems and physical applications is outlined. It is then shown that all generalised retarded functions constructed from any one set of bosonic fields are equal at zero energy. This is done completely generally and is not limited to any approximation scheme such as perturbation theory.
منابع مشابه
Thermal Bosonic Green Functions Near Zero Energy
The properties of the various types of bosonic Green functions at finite temperature in the zero energy limit are considered in the light of recent work. Nous discutons, à la lumière de récents travaux, des propriétés de certains types de fonctions de Green à température finie, dans le cas limite où l’énergie est nulle.
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