Generic Rules for High Temperature Dimensional Reduction and Their Application to the Standard Model
K. Kajantie, M. Laine, K. Rummukainen, M. Shaposhnikov
TL;DR
The paper develops a general framework for high-temperature dimensional reduction of gauge theories to a 3d bosonic effective theory by matching static Green's functions, and applies it to map the Standard Model electroweak sector onto a 3d $SU(2)\times U(1)$ gauge-Higgs theory. It provides explicit 1-loop and 2-loop building blocks, derives the relations between 4d MSbar parameters and the 3d theory, and addresses the role of higher-order operators and infrared safety. The approach yields a practical pathway to study electroweak phase transitions nonperturbatively via lattice simulations of the 3d theory and to explore extensions of the SM within a universal 3d framework. The results include detailed mappings of SM parameters to 3d couplings, numerical assessments as functions of $m_H$ and temperature, and a discussion of perturbative and nonperturbative implications for early-universe cosmology and beyond-Standard-Model scenarios.
Abstract
We formulate the rules for dimensional reduction of a generic finite temperature gauge theory to a simpler three-dimensional effective bosonic theory in terms of a matching of Green's functions in the full and the effective theory, and present a computation of a generic set of 1- and 2-loop graphs needed for the application of these rules. As a concrete application we determine the explicit mapping of the physical parameters of the standard electroweak theory to a three-dimensional SU(2)xU(1) gauge-Higgs theory. We argue that this three-dimensional theory has a universal character and appears as an effective theory for many extensions of the Standard Model.
