000136115 001__ 136115 000136115 005__ 20240711103552.0 000136115 0247_ $$2doi$$a10.3390/physics6020040 000136115 0248_ $$2sideral$$a139050 000136115 037__ $$aART-2024-139050 000136115 041__ $$aeng 000136115 100__ $$0(orcid)0000-0003-3669-6241$$aAsorey, Manuel$$uUniversidad de Zaragoza 000136115 245__ $$aCasimir Energy in (2 + 1)-Dimensional Field Theories 000136115 260__ $$c2024 000136115 5060_ $$aAccess copy available to the general public$$fUnrestricted 000136115 5203_ $$aWe explore the dependence of vacuum energy on the boundary conditions for massive scalar fields in (2 + 1)-dimensional spacetimes. We consider the simplest geometrical setup given by a two-dimensional space bounded by two homogeneous parallel wires in order to compare it with the non-perturbative behaviour of the Casimir energy for non-Abelian gauge theories in (2 + 1) dimensions. Our results show the existence of two types of boundary conditions which give rise to two different asymptotic exponential decay regimes of the Casimir energy at large distances. The two families are distinguished by the feature that the boundary conditions involve or not interrelations between the behaviour of the fields at the two boundaries. Non-perturbative numerical simulations and analytical arguments show such an exponential decay for Dirichlet boundary conditions of SU(2) gauge theories. The verification that this behaviour is modified for other types of boundary conditions requires further numerical work. Subdominant corrections in the low-temperature regime are very relevant for numerical simulations, and they are also analysed in this paper. 000136115 536__ $$9info:eu-repo/grantAgreement/ES/DGA-FSE/E21-17R$$9info:eu-repo/grantAgreement/ES/MICINN/PGC2022-126078NB-C21 000136115 540__ $$9info:eu-repo/semantics/openAccess$$aby$$uhttp://creativecommons.org/licenses/by/3.0/es/ 000136115 655_4 $$ainfo:eu-repo/semantics/article$$vinfo:eu-repo/semantics/publishedVersion 000136115 700__ $$aIuliano, Claudio 000136115 700__ $$aEzquerro, Fernando$$uUniversidad de Zaragoza 000136115 7102_ $$12004$$2405$$aUniversidad de Zaragoza$$bDpto. Física Teórica$$cÁrea Física Teórica 000136115 773__ $$g6, 2 (2024), 613-628$$tPhysics (Switzerland)$$x2624-8174 000136115 8564_ $$s636787$$uhttps://zaguan.unizar.es/record/136115/files/texto_completo.pdf$$yVersión publicada 000136115 8564_ $$s2569567$$uhttps://zaguan.unizar.es/record/136115/files/texto_completo.jpg?subformat=icon$$xicon$$yVersión publicada 000136115 909CO $$ooai:zaguan.unizar.es:136115$$particulos$$pdriver 000136115 951__ $$a2024-07-11-08:38:37 000136115 980__ $$aARTICLE