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arXiv · 1610.04495

Compensating strong coupling with large charge

Luis Alvarez-Gaume·Orestis Loukas·Domenico Orlando·Susanne Reffert
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Abstract

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 [Hellerman et al. 2015], that the effective field theory describing such sector of fixed $Q$ contains effective couplings $λ_{\text{eff}}\sim λ^b /Q^{a}$, 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.

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Luis Alvarez-Gaume, Orestis Loukas, Domenico Orlando, Susanne Reffert. 2017-03-20. Compensating strong coupling with large charge. https://doi.org/10.1007/jhep04(2017)059

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