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Effective potential at finite temperature in a constant magnetic field I: Ring diagrams in a scalar theory

Alejandro Ayala·Angel Sánchez·Gabriella Piccinelli·Sarira Sahu
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Abstract

We study symmetry restoration at finite temperature in the theory of a charged scalar field interacting with a constant, external magnetic field. We compute the finite temperature effective potential including the contribution from ring diagrams. We show that in the weak field case, the presence of the field produces a stronger first order phase transition and that the temperature for the onset of the transition is lower, as compared to the case without magnetic field.

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Alejandro Ayala, Angel Sánchez, Gabriella Piccinelli, Sarira Sahu. 2005-02-01. Effective potential at finite temperature in a constant magnetic field I: Ring diagrams in a scalar theory. https://doi.org/10.1103/physrevd.71.023004

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