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Looking for defects in the 2PI correlator

Arttu Rajantie·Anders Tranberg
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Abstract

Truncations of the 2PI effective action are seen as a promising way of studying non-equilibrium dynamics in quantum field theories. We probe their applicability in the non-perturbative setting of topological defect formation in a symmetry-breaking phase transition, by comparing full classical lattice field simulations and the 2PI formulation for classical fields in an O($N$) symmetric scalar field theory. At next-to-leading order in 1/N, the 2PI formalism fails to reproduce any signals of defects in the two-point function. This suggests that one should be careful when applying the 2PI formalism for symmetry breaking phase transitions.

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Arttu Rajantie, Anders Tranberg. 2006-07-26. Looking for defects in the 2PI correlator. https://doi.org/10.1088/1126-6708%2F2006%2F11%2F020

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