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arXiv · 2104.13003

Excitation Spectrum for Bose Gases beyond the Gross-Pitaevskii Regime

Christian Brennecke·Marco Caporaletti·Benjamin Schlein
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Abstract

We consider Bose gases of $N$ particles in a box of volume one, interacting through a repulsive potential with scattering length of order $N^{1-\kappa}$, for $\kappa > 0$. Such regimes interpolate between the Gross-Pitaevskii and thermodynamic limits. Assuming that $\kappa$ is sufficiently small, we determine the ground state energy and the low-energy excitation spectrum of the system, up to errors vanishing in the limit of large $N$.

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Christian Brennecke, Marco Caporaletti, Benjamin Schlein. 2021-04-27. Excitation Spectrum for Bose Gases beyond the Gross-Pitaevskii Regime. https://doi.org/10.1142/s0129055x22500271

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