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arXiv · 1612.00386

(Non)-universality of vortex reconnections in superfluids

Alberto Villois·Giorgio Krstulovic·Davide Proment
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Abstract

An insight into vortex reconnections in superfluids is presented making use of analytical results and numerical simulations of the Gross--Pitaevskii model. Universal aspects of the reconnection process are investigated by considering different initial vortex configurations and making use of a recently developed tracking algorithm to reconstruct the vortex filaments. We show that during a reconnection event the vortex lines approach and separate always accordingly to the time scaling $ \delta \sim t^{1/2} $ with pre-factors that depend on the vortex configuration. We also investigate the behavior of curvature and torsion close to the reconnection point, demonstrating analytically that the curvature can exhibit a self-similar behavior that might be broken by the development of shock-like structures in the torsion.

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Alberto Villois, Giorgio Krstulovic, Davide Proment. 2016-12-01. (Non)-universality of vortex reconnections in superfluids. https://doi.org/10.1103/physrevfluids.2.044701

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