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arXiv · 1403.2761

Maximum-Likelihood Approach to Topological Charge Fluctuations in Lattice Gauge Theory

R. C. Brower·M. Cheng·G. T. Fleming·M. F. Lin·E. T. Neil·J. C. Osborn·C. Rebbi·E. Rinaldi·D. Schaich·C. Schroeder·G. Voronov·P. Vranas·E. Weinberg·O. Witzel
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Abstract

We present a novel technique for the determination of the topological susceptibility (related to the variance of the distribution of global topological charge) from lattice gauge theory simulations, based on maximum-likelihood analysis of the Markov-chain Monte Carlo time series. This technique is expected to be particularly useful in situations where relatively few tunneling events are observed. Restriction to a lattice subvolume on which topological charge is not quantized is explored, and may lead to further improvement when the global topology is poorly sampled. We test our proposed method on a set of lattice data, and compare it to traditional methods.

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R. C. Brower, M. Cheng, G. T. Fleming, M. F. Lin, E. T. Neil, J. C. Osborn, C. Rebbi, E. Rinaldi, D. Schaich, C. Schroeder, G. Voronov, P. Vranas, E. Weinberg, O. Witzel. 2014-07-24. Maximum-Likelihood Approach to Topological Charge Fluctuations in Lattice Gauge Theory. https://doi.org/10.1103/physrevd.90.014503

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