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arXiv · hep-ph/0301225

Dynamical mass generation for fermions in quenched Quantum Electrodynamics at finite temperature

Abstract

We study the dynamical generation of masses for fundamental fermions in quenched quantum electrodynamics (qQED) at finite temperature in the bare vertex approximation, using Schwinger-Dyson equations (SDE). Motivated by perturbation theory, a further simplification is introduced by taking the wave function renormalization to be unity. In the zeroth mode approximation, the SDE for the fermion propagator resembles QED in 2+1 dimensions (QED3) at zero temperature with an effective dimensionful coupling alpha'=alpha T. For a fixed temperature, mass is dynamically generated above a certain critical value of this coupling. As expected, raising the temperature restores chiral symmetry and fermions become massless again. We also argue that by summing over the frequency modes and under suitable simplifications, qualitative aspects of the result do not undergo significant changes.

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Alejandro Ayala, Adnan Bashir. 2003-04-24. Dynamical mass generation for fermions in quenched Quantum Electrodynamics at finite temperature. https://doi.org/10.1103/physrevd.67.076005

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