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arXiv · hep-th/9605024

Exact CTP Renormalization Group Equation for the Coarse Grained Effective Action

Diego A. R. Dalvit·Francisco D. Mazzitelli
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Abstract

We consider a scalar field theory in Minkowski spacetime and define a coarse grained Closed Time Path (CTP) effective action by integrating quantum fluctuations of wavelengths shorter than a critical value. We derive an exact CTP renormalization group equation and solve it using a derivative expansion approach. Explicit calculation is performed for the $λϕ^4$ theory. We discuss the relevance of the CTP average action in the study of non-equilibrium aspects of phase transitions in quantum field theory.

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Diego A. R. Dalvit, Francisco D. Mazzitelli. 1996-11-11. Exact CTP Renormalization Group Equation for the Coarse Grained Effective Action. https://doi.org/10.1103/physrevd.54.6338

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