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Compensating strong coupling with large charge

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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 effλ 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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Correspondence to Susanne Reffert.

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ArXiv ePrint: 1610.04495

On leave of absence from the Department of Theoretical Physics, CERN, Switzerland. (Luis Alvarez-Gaume)

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Alvarez-Gaume, L., Loukas, O., Orlando, D. et al. Compensating strong coupling with large charge. J. High Energ. Phys. 2017, 59 (2017).

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  • Conformal Field Theory
  • Effective Field Theories
  • Global Symmetries
  • Spontaneous Symmetry Breaking