2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/54343We introduce an approach for calculating the quantum loop corrections in the $ϕ^4$ theory. Differential regularization and background-field method are essential tools and are used to calculate the effective action of the theory to two-loop order. Our approach is considerably simpler than other known methods and can be readily extended to higher-loop calculations and to other models.12 pagesHigh Energy Physics - Theorytext