Compensating strong coupling with large charge

• Published in: The journal of high energy physics Vol. 2017; no. 4; pp. 1 - 21
• Main Authors: Alvarez-Gaume, Luis, Loukas, Orestis, Orlando, Domenico, Reffert, Susanne
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.04.2017; Springer Nature B.V; SpringerOpen
• Subjects: Classical and Quantum Gravitation; Conformal Field Theory; Coupling; Couplings; Effective Field Theories; Elementary Particles; Energy industry; Field theory; Global Symmetries; High energy physics; Hilbert space; Low energy; Mathematical models; Physics; Physics and Astronomy; Quantum Field Theories; Quantum Field Theory; Quantum Physics; Regular Article - Theoretical Physics; Relativity Theory; Spontaneous Symmetry Breaking; String Theory; Symmetry; Theorems; Theoretical physics; Values; Global Symmetries; Effective Field Theories; Spontaneous Symmetry Breaking; Conformal Field Theory
• ISSN: 1029-8479; 1029-8479
• DOI: 10.1007/JHEP04(2017)059

A bstract We study some (conformal) field theories with global symmetries in the sector where the value of the global charge Q is large. We find (as expected) that the low energy excitations of this sector are described by the general form of Goldstone’s theorem in the non-relativistic regime. We also derive the unexpected result, first presented in [ 1 ], that the effective field theory describing such sector of fixed Q contains effective couplings λ eff ∼ λ b / Q a , where λ is the original coupling. Hence, large charge leads to weak coupling. In the last section of the paper we present an outline of how to compute anomalous dimensions of the O ( n ) model in this limit.