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arXiv · hep-ph/0207346

Dynamics of broken symmetry lambda phi^4 field theory

Abstract

We study the domain of validity of a Schwinger-Dyson (SD) approach to non-equilibrium dynamics when there is broken symmetry. We perform exact numerical simulations of the one- and two-point functions of lambda phi^4 field theory in 1+1 dimensions in the classical domain for initial conditions where < phi(x) > not equal to 0. We compare these results to two self-consistent truncations of the SD equations which ignore three-point vertex function corrections. The first approximation, which sets the three-point function to one (the bare vertex approximation (BVA)) gives an excellent description for < phi(x) > = phi(t). The second approximation which ignores higher in 1/N corrections to the 2-PI generating functional (2PI -1/N expansion) is not as accurate for phi(t). Both approximations have serious deficiencies in describing the two-point function when phi(0) > .4.

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BibTeXRIS

Fred Cooper, John F. Dawson, Bogdan Mihaila. 2002-10-30. Dynamics of broken symmetry lambda phi^4 field theory. https://doi.org/10.1103/physrevd.67.051901

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