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arXiv · 0707.0396

Finite volume QCD at fixed topological charge

Sinya Aoki·Hidenori Fukaya·Shoji Hashimoto·Tetsuya Onogi
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Abstract

In finite volume the partition function of QCD with a given $θ$ is a sum of different topological sectors with a weight primarily determined by the topological susceptibility. If a physical observable is evaluated only in a fixed topological sector, the result deviates from the true expectation value by an amount proportional to the inverse space-time volume 1/V. Using the saddle point expansion, we derive formulas to express the correction due to the fixed topological charge in terms of a 1/V expansion. Applying this formula, we propose a class of methods to determine the topological susceptibility in QCD from various correlation functions calculated in a fixed topological sector.

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Sinya Aoki, Hidenori Fukaya, Shoji Hashimoto, Tetsuya Onogi. 2007-07-19. Finite volume QCD at fixed topological charge. https://doi.org/10.1103/physrevd.76.054508

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