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arXiv · 2110.14009

Finite-density QCD, $\mathcal{PT}$ symmetry, and dual algorithms

Moses A. Schindler·Stella T. Schindler·Michael C. Ogilvie
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Abstract

Finite-density QCD and many other field theories with sign problems have a $\mathcal{PT}$-type symmetry. After a brief introduction to $\mathcal{PT}$-symmetric field theories, a real dual representation for $\mathcal{PT}$-symmetric scalar field theories with complex actions is derived. We show that $\mathcal{PT}$-symmetric field theories can exhibit exotic behavior, including sinusoidally modulated propagators, disorder lines, and spatially inhomogeneous pattern-forming phases. We discuss the interplay of duality, $\mathcal{PT}$-symmetry and pattern formation using a $\phi^4$ model and $Z(N)$ spin model with sign problems as examples. These behaviors may occur in finite-density QCD and related models.

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Moses A. Schindler, Stella T. Schindler, Michael C. Ogilvie. 2021-10-26. Finite-density QCD, $\mathcal{PT}$ symmetry, and dual algorithms. https://arxiv.org/abs/2110.14009

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