Positivity in Perturbative Renormalization: an EFT $a$-theorem

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: Liao, You-Peng, Nepveu, Jasper Roosmale, Shen, Chia-Hsien
Format: Preprint
Publié: 2025
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866910928443801600
author Liao, You-Peng
Nepveu, Jasper Roosmale
Shen, Chia-Hsien
author_facet Liao, You-Peng
Nepveu, Jasper Roosmale
Shen, Chia-Hsien
contents We show that the direction of renormalization in effective field theory is constrained by fundamental principles in the infrared$\unicode{x2014}$unitarity, analyticity, and Lorentz invariance. Our theorem, in the spirit of the $a$-theorem in conformal field theory, determines the sign of the one-loop running of couplings in the forward limit, when one inserts two operators whose mass dimensions are identical and even. The theorem holds for a broad class of effective field theories with arbitrary ultraviolet completions. The constraint directly applies to linear positivity bounds derived using tree-level amplitudes in the IR, providing a criterion for whether renormalization effects can preserve the positivity bounds, or lead to their apparent violation. We discuss the phenomenological implications of our theorem in chiral perturbation theory and the Standard Model Effective Field Theory, where our theorem is particularly constraining for the running at dimension eight. We provide several examples and show various extensions and applications even at dimension six.
format Preprint
id arxiv_https___arxiv_org_abs_2505_02910
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Positivity in Perturbative Renormalization: an EFT $a$-theorem
Liao, You-Peng
Nepveu, Jasper Roosmale
Shen, Chia-Hsien
High Energy Physics - Phenomenology
High Energy Physics - Theory
We show that the direction of renormalization in effective field theory is constrained by fundamental principles in the infrared$\unicode{x2014}$unitarity, analyticity, and Lorentz invariance. Our theorem, in the spirit of the $a$-theorem in conformal field theory, determines the sign of the one-loop running of couplings in the forward limit, when one inserts two operators whose mass dimensions are identical and even. The theorem holds for a broad class of effective field theories with arbitrary ultraviolet completions. The constraint directly applies to linear positivity bounds derived using tree-level amplitudes in the IR, providing a criterion for whether renormalization effects can preserve the positivity bounds, or lead to their apparent violation. We discuss the phenomenological implications of our theorem in chiral perturbation theory and the Standard Model Effective Field Theory, where our theorem is particularly constraining for the running at dimension eight. We provide several examples and show various extensions and applications even at dimension six.
title Positivity in Perturbative Renormalization: an EFT $a$-theorem
topic High Energy Physics - Phenomenology
High Energy Physics - Theory
url https://arxiv.org/abs/2505.02910