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arXiv · 2003.02070

Obtaining the sphaleron field configurations with gradient flow

Yu Hamada·Kengo Kikuchi
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Abstract

We propose a formalism to obtain the electroweak sphaleron, which is one of the static classical solutions, using the gradient flow method. By adding a modification term to the gradient flow equation, we can obtain the sphaleron configuration as a stable fixed point of the flow in the large flow time. Applying the method to the $SU(2)$-Higgs model (the Weinberg angle $\theta_W$ is $0$) in four dimensions, we obtain the sphaleron configuration whose energy coincides with previous studies numerically. We can also show that the Chern-Simons number of the solution has a half-integer.

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Yu Hamada, Kengo Kikuchi. 2020-03-04. Obtaining the sphaleron field configurations with gradient flow. https://doi.org/10.1103/physrevd.101.096014

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