Thermal Operator Representation of Feynman Graphs
نویسنده
چکیده
In this talk I describe an interesting relation between Feynman graphs at finite temperature and chemical potential and the corresponding ones at zero temperature. The operator relating the two which we call the “thermal operator”, simplifies the evaluation of finite temperature graphs and helps in understanding better several physical questions such as cutting rules, forward scattering, gauge invariance etc at finite temperature.
منابع مشابه
Thermal Operator Representation of Finite-Temperature Amplitudes in the Presence of Chemical Potential
In a recent paper [Phys. Rev. D 72, 085006 (2005)], Brandt et al. deduced the thermal operator representation for a thermal N -point amplitude, both in the imaginary-time and real-time formalisms. In the case when a chemical potential present, however, the representation is not as simple as in the case with vanishing chemical potential. We propose a much simpler and transparent representation f...
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