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arXiv · 1202.2721

Validity of the kink approximation to the tunneling action

Koushik Dutta·Cecelie Hector·Thomas Konstandin·Pascal M. Vaudrevange·Alexander Westphal
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Abstract

Coleman tunneling in a general scalar potential with two non-degenerate minima is known to have an approximation in terms of a piecewise linear triangular-shaped potential with sharp 'kinks' at the place of the local minima. This approximate potential has a regime where the existence of the bounce solution needs the scalar field to 'wait' for some amount of Euclidean time at one of the 'kinks'. We discuss under which conditions a kink approximation of locally smooth 'cap' regions provides a good estimate for the bounce action.

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Koushik Dutta, Cecelie Hector, Thomas Konstandin, Pascal M. Vaudrevange, Alexander Westphal. 2013-01-10. Validity of the kink approximation to the tunneling action. https://doi.org/10.1103/physrevd.86.123517

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