arXiv subjects

Michelli S. R. Sarges

Publications and source records attributed to Michelli S. R. Sarges.

3 recordsLinked to original sources

arXiv2026

Effective Lagrangian of a fermion field in a nontrivial topology under magnetic effects

We have investigated a fermionic system from the perspective of an effective quantum field theory defined on a nontrivial topology in the presence of an external magnetic field. Using the proper-time representation, we obtained one-loop expressions for the corresponding effective Lagrangian, taking into account all Landau levels in the propagator. We also computed the significant boundary-induced contributions to the system's magnetization. To verify the reliability of our results, we examined the limit of zero temperature and infinite spatial extent, which correctly reproduces the celebrated Schwinger result.

hep-th↗

arXiv2025

Green's functions under magnetic effects in a nontrivial topology

We calculate the Bose and Dirac field propagators in a four-dimensional Euclidean space under a magnetic external field by using a hybrid version of the Ritus and Schwinger methods. We get both propagators explicitly in the coordinate and momentum domains without dimensional reduction. Through gauge transformations, we eliminate the translation non-invariant part of the propagators. Also, the Matsubara frequencies of the fields are obtained in a toroidal topology. The approach we consider in this paper has the advantage of taking into account thermal and finite-volume effects with several kinds of boundary conditions, in addition to considering all Landau levels simultaneously, in an analytical and tractable way.

hep-th↗

arXiv2025

Boundary conditions and electromagnetic effects on the phase transition of a zero spin bosonic system

In the following paper, we will study a charged scalar field under an electromagnetic external field taking into account the spatial confining of the system. We shall use the Coleman-Weinberg method in one-loop approximation to obtain the effective potential of the model in the proper time representation. Through generalized Matsubara formalism, we applied several kinds of boundary conditions on the frontier of the system. The regularization of the model is performed by a scheme independent of the external electromagnetic applied field. The model presents phase transition and we carry out its analysis by the free energy density functional of the bosonic system. The findings show magnetic catalysis, electric catalysis, and inverse electric catalysis phenomena, all of them depending on the thickness of the system.

hep-th↗