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  • Letter
  • Open Access

Sign optimization and complex saddle points in one-dimensional QCD

Gökçe Başar* and Joseph Marincel†

  • Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27599, USA

  • *gbasar@unc.edu
  • †marincel@unc.edu
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Phys. Rev. D 106, L091503 – Published 16 November, 2022

DOI: https://doi.org/10.1103/PhysRevD.106.L091503

Abstract

We study one-dimensional QCD at finite quark density by using the sign optimization framework. The fermion sign problem is mitigated by deforming the path integral domain SU(3) to a complexified one M⊂SL(3), explicitly constructed to reduce the phase fluctuations. The complexification is constructed using the angular representation of SU(3). We provide a physical explanation of the optimization procedure in terms of complex saddle points. This picture connects the sign optimization framework to the generalized Lefschetz thimbles.

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Phys. Rev. D 106, L091503– Published 16 November, 2022
  • Received 24 August 2022
  • Accepted 1 November 2022
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