Heavy-dense QCD, sign optimization and Lefschetz thimbles

Gokce Basar; Joseph Marincel

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arXiv · 2311.06343

Heavy-dense QCD, sign optimization and Lefschetz thimbles

Gokce Basar·Joseph Marincel

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Abstract

We study the heavy-dense limit of QCD on the lattice with heavy quarks at high density. The effective three dimensional theory has a sign problem which is alleviated by sign optimization where the path integration domain is deformed in complex space in a way that minimizes the phase oscillations. We simulate the theory via a Hybrid-Monte-Carlo, for different volumes, both to leading order and next-to-next-to leading order in the hopping expansion, and show that sign optimization successfully mitigates the sign problem at large enough volumes where usual re-weighting methods fail. Finally we show that there is a significant overlap between the complex manifold generated by sign optimization and the Lefschetz thimbles associated with the theory.

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Gokce Basar, Joseph Marincel. 2023-11-10. Heavy-dense QCD, sign optimization and Lefschetz thimbles. https://arxiv.org/abs/2311.06343

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