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arXiv · 2210.05507

The Sphaleron Rate from 4D Euclidean Lattices

Marc Barroso Mancha·Guy D. Moore
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Abstract

We develop a new method to determine thermal activation rates, such as for bubble nucleation, topology change, \textsl{etc.}, using 4-dimensional Euclidean methods. This allows nonperturbative study on the lattice. We then investigate the strong sphaleron rate in pure-glue QCD at temperatures between 1.3 $\Tc$ and 1000 $T_\mathrm{c}$, making contact with previous results but extending them down close to the critical temperature. The extension to full QCD will be straightforward. Limitations of the proposal (the inability to compute a certain dynamical prefactor, puzzling large-volume behavior, and the inability to treat temperatures $T < 1.3 \, T_\mathrm{c}$) are also discussed.

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BibTeXRIS

Marc Barroso Mancha, Guy D. Moore. 2022-10-11. The Sphaleron Rate from 4D Euclidean Lattices. https://doi.org/10.1007/jhep01(2023)155

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