The 2D Lorentz-violating fermionic Casimir effect under thermal conditions

Abstract

In the present work, we study a fermionic Lorentz invariance violation (LIV) theory with a CPT-even extension and analyze its impact on the Casimir effect under the MIT bag boundary condition model in a low-dimensional setting, where results are obtained without any approximations for a null-temperature system. Moreover, the Matsubara formalism is applied to derive closed expressions for the influence of temperature on the physical observables: Casimir energy, Casimir force, and entropy associated with the system in a LIV context. For each thermal observable, the influence of the LIV correction term is considered in the analysis of both low- and high-temperature regimes. Additionally, we construct a condensed matter analogue using the SSH model, where nonlinear fermionic dispersion and boundary-induced vacuum energy emerge, reproducing the analytical structure of the LIV Casimir effect.