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arXiv · 1904.04000

Derivation of the time-dependent Gross-Pitaevskii equation for the dipolar gases

Arnaud Triay
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Abstract

We derive the time-dependent dipolar Gross-Pitaevskii (GP) equation from the N-body Schr{\"o}dinger equation. More precisely we show a norm approximation for the solution of the many body equation as well as the convergence of its one-body reduced density matrix towards the orthogonal projector onto the solution of the dipolar GP equation. We consider the interpolation regime where interaction potential is scaled like $N^{3\beta--1} w(N^\beta (x -- y))$, the range of validity of $\beta$ depends on the stability of the ground state problem. In particular we can prove the convergence on the one-body density matrix assuming $\widehat{w} $\ge$ 0$ and $\beta < 3/8$.

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Arnaud Triay. 2019-04-08. Derivation of the time-dependent Gross-Pitaevskii equation for the dipolar gases. https://arxiv.org/abs/1904.04000

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