On the hydrodynamic canonical formalism of the Gross-Pitaevskii field

Yvan Buggy; Patrik Öhberg

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arXiv · 1908.07090

On the hydrodynamic canonical formalism of the Gross-Pitaevskii field

Yvan Buggy·Patrik Öhberg

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Abstract

We derive a canonical formalism for the hydrodynamic representation of the Gross-Pitaevskii field (nonlinear Schr\"odinger field), where the density and the phase of the condensate form a canonical pair of conjugate field variables. To do so, we treat the meanfield as a singular Lagrangian system and apply both the Dirac-Bergmann and Faddeev-Jackiw methods. The Faddeev-Jackiw method is found to be a more direct approach to the problem.

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Yvan Buggy, Patrik Öhberg. 2019-08-19. On the hydrodynamic canonical formalism of the Gross-Pitaevskii field. https://arxiv.org/abs/1908.07090

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