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arXiv · 1703.02414

Tempered transitions between thimbles

Andrei Alexandru·Gokce Basar·Paulo F. Bedaque·Neill C. Warrington
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Abstract

Quantum field theories with complex actions cannot be investigated using importance sampling due to the sign problem. One possible solution is to use the holomorphic gradient flow, a method we introduced related to the Lefschetz thimbles idea. In many cases the probability distribution generated by this method is multi-modal and standard Monte-Carlo sampling fails. We propose an algorithm that incorporates tempered proposals to solve this problem. We apply this algorithm to the 0+1 dimensional Thirring model at finite density for a parameter set where standard sampling fails and show that tempered proposals cure this problem.

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Andrei Alexandru, Gokce Basar, Paulo F. Bedaque, Neill C. Warrington. 2017-03-07. Tempered transitions between thimbles. https://doi.org/10.1103/physrevd.96.034513

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