https://doi.org/10.1140/epjc/s10052-017-5450-0
Regular Article - Theoretical Physics
High-temperature expansion of the one-loop effective action induced by scalar and Dirac particles
Physics Faculty, Tomsk State University, Tomsk, 634050, Russia
* e-mail: probustom@gmail.com
Received:
23
August
2017
Accepted:
5
December
2017
Published online:
18
December
2017
The complete nonperturbative expressions for the high-temperature expansion of the one-loop effective action induced by the charged scalar and the charged Dirac particles both at zero and finite temperatures are derived with account of possible nontrivial boundary conditions. The background electromagnetic field is assumed to be stationary and such that the corresponding Klein–Gordon operator or the Dirac Hamiltonian is self-adjoint. The contributions of particles and antiparticles are obtained separately. The explicit expressions for the C-symmetric and the non-C-symmetric vacuum energies of the Dirac fermions are derived. The leading corrections to the high-temperature expansion due to the nontrivial boundary conditions are explicitly found. The corrections to the logarithmic divergence of the effective action that come from the boundary conditions are derived. The high-temperature expansion of the naive one-loop effective action induced by charged fermions turns out to be divergent in the limit of a zero fermion mass.
© The Author(s), 2017