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arXiv · hep-ph/9604444

Non-equilibrium symmetry restoration beyond one loop

A. Riotto·I. I. Tkachev
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Abstract

We calculate the strength of symmetry restoration effects in highly non-equilibrium states which can arise, for example, during preheating after inflation. We show that in certain parameter range the one-loop results are unstable, requiring summation of multiloop diagrams. We solve this problem for the $O(N)$ model in the large $N$-limit and show that the symmetry restoration may be less effective than what predicted by the one-loop estimate.

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A. Riotto, I. I. Tkachev. 1996-04-30. Non-equilibrium symmetry restoration beyond one loop. https://doi.org/10.1016/0370-2693(96)00882-9

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