Equilibrium and Non-equilibrium Quantum Field Theory
نویسنده
چکیده
We first focus in Chapter 2 on infrared effects in finite–temperature quantum field theory. We propose a simple mathematical method (based on the largest–time equation and the Dyson–Schwinger equations) which allows systematic calculations of the change of density in energy/particles in heat–bath during a scattering/decay of external particles within the heat bath. A careful analysis reveals that the resulting changes in the energy density are finite even in the case of massless heat–bath particles (no infrared catastrophe).
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