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arXiv · 0811.1850

Two complex problems on the lattice: transport coefficients and finite chemical potential

Gert Aarts
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Abstract

After a few remarks about the problem of extracting transport coefficients from lattice QCD calculations, I report on recent developments in applying stochastic quantization and complex Langevin dynamics to field theories with a complex action due to a nonzero chemical potential. First results demonstrate that the sign problem poses no obstacle for this approach, even in the thermodynamic limit. I conclude with a comparison of two simple one-link models, describing a euclidean system at finite chemical potential and a Minkowski system in real time.

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Gert Aarts. 2008-11-12. Two complex problems on the lattice: transport coefficients and finite chemical potential. https://doi.org/10.1016/j.nuclphysa.2009.01.019

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