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arXiv · 2305.12271

Electric current from Schwinger's time-ordered propagator

Cristian Villavicencio
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Abstract

The quasistatic electric current density of fermions in the presence of an external electric field is determined through the utilization of a time-ordered Schwinger propagator. The study encompasses the necessary conditions for establishing a well-defined time-ordered propagator within the Schwinger formalism, specifically concentrating on constant and uniform electromagnetic fields. Within this theoretical framework, a chemical potential is introduced, resulting in non-zero values for the electric current and charge number density. Consequently, the dependence of electric conductivity on the strength of the electric field and the charge number density is investigated.

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Cristian Villavicencio. 2023-05-20. Electric current from Schwinger's time-ordered propagator. https://doi.org/10.31349/revmexfis.72.010801

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