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arXiv · 1603.05630

Interpreting Numerical Measurements in Fixed Topological Sectors

Wolfgang Bietenholz·Christopher Czaban·Arthur Dromard·Urs Gerber·Christoph P. Hofmann·Héctor Mejía-Díaz·Marc Wagner
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Abstract

For quantum field theories with topological sectors, Monte Carlo simulations on fine lattices tend to be obstructed by an extremely long auto-correlation time with respect to the topological charge. Then reliable numerical measurements are feasible only within individual sectors. The challenge is to assemble such restricted measurements in a way that leads to a substantiated approximation to the fully fledged result, which would correspond to the correct sampling over the entire set of configurations. We test an approach for such a topological summation, which was suggested by Brower, Chandrasekharan, Negele and Wiese. Under suitable conditions, energy levels and susceptibilities can be obtained to a good accuracy, as we demonstrate for O(N) models, SU(2) Yang-Mills theory, and for the Schwinger model.

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Wolfgang Bietenholz, Christopher Czaban, Arthur Dromard, Urs Gerber, Christoph P. Hofmann, Héctor Mejía-Díaz, Marc Wagner. 2016-03-17. Interpreting Numerical Measurements in Fixed Topological Sectors. https://doi.org/10.1103/physrevd.93.114516

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