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arXiv · hep-ph/9809339

The Classical Approximation for Real-Time Scalar Field Theory at Finite Temperature

Gert Aarts
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Abstract

The use of classical thermal field to approximate real-time quantum thermal field theory is discussed. For a λϕ^4 theory, it is shown that the classical Rayleigh-Jeans divergence can be canceled with the appropriate counterterms, and a comparison is made between the classical and quantum perturbative expansion. It is explained why Hard Thermal Loops prevent the same method to work for gauge theories.

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Gert Aarts. 1998-09-11. The Classical Approximation for Real-Time Scalar Field Theory at Finite Temperature. https://arxiv.org/abs/hep-ph/9809339

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