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arXiv · hep-lat/0110122

Measuring infrared contributions to the QCD pressure

K. Kajantie·M. Laine·K. Rummukainen·Y. Schroder
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Abstract

For the pressure (or free energy) of QCD, four-dimensional (4d) lattice data is available at zero baryon density up to a few times the critical temperature $T_c$. Perturbation theory, on the other hand, has serious convergence problems even at very high temperatures. In a combined analytical and three-dimensional (3d) lattice method, we show that it is possible to compute the QCD pressure from about $2 T_c$ to infinity. The numerical accuracy is good enough to resolve in principle, e.g., logarithmic contributions related to 4-loop perturbation theory.

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K. Kajantie, M. Laine, K. Rummukainen, Y. Schroder. 2001-10-15. Measuring infrared contributions to the QCD pressure. https://doi.org/10.1016/s0920-5632(01)01768-6

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