Fermion number of twisted kinks in the NJL 2 model revisited

  title={Fermion number of twisted kinks in the NJL 2 model revisited},
  author={Michael Thies},
  journal={Physical Review D},
  • M. Thies
  • Published 10 October 2017
  • Physics
  • Physical Review D
As a consequence of axial current conservation, fermions cannot be localized in the massless NJL$_2$ model. In the case of twisted kinks, this manifests itself in a cancellation between valence fermion density and fermion density induced in the Dirac sea. To attribute the correct fermion number to these bound states requires an infrared regularization. Recently, this has been achieved by introducing a bare fermion mass, at least in the non-relativistic regime of small twist angles and fermion… 

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