Functional Matching and Renormalization Group Equations at Two-Loop Order

Autor: Fuentes-Martín, Javier, Palavrić, Ajdin, Thomsen, Anders Eller
Rok vydání: 2023
Předmět:
Zdroj: Phys.Lett.B 851 (2024) 138557
Druh dokumentu: Working Paper
DOI: 10.1016/j.physletb.2024.138557
Popis: We present a systematic method for determining the two-loop effective Lagrangian resulting from integrating out a set of heavy particles in an ultraviolet scalar theory. We prove that the matching coefficients are entirely determined from the (double-)hard region of the loop integrals and present a master formula for matching, applicable to both diagrammatic and functional approaches. We further employ functional methods to determine compact expressions for the effective Lagrangian that do not rely on any previous knowledge of its structure or symmetries. The same methods are also applicable to the computation of renormalization group equations. We demonstrate the application of the functional approach by computing the two-loop matching coefficients and renormalization group equations in a scalar toy model.
Comment: 13 pages, 2 figures. v2: Matching journal version
Databáze: arXiv