Compensating strong coupling with large charge

  title={Compensating strong coupling with large charge},
  author={Lu{\'i}s Alvarez-Gaum{\'e} and Orestis Loukas and Domenico Orlando and Susanne Reffert},
  journal={Journal of High Energy Physics},
A bstractWe 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 λeff ∼ λb/Qa, where λ is the original coupling… 
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