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Variational approximation for two-time correlation functions in $Φ^4$ theory : optimization of the dynamics

Cécile Martin
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Abstract

We apply the time-dependent variational principle of Balian and Vénéroni to the $ Φ^4$ theory. An appropriate parametrization for the variational objects allows us to write coupled dynamical equations from which we derive approximations for the two-time correlation functions involving two, three or four field operators.

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Cécile Martin. 1995-05-05. Variational approximation for two-time correlation functions in $Φ^4$ theory : optimization of the dynamics. https://doi.org/10.1103/physrevd.52.7121

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