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arXiv · 2310.11347

Diagonalizing Bose Gases in the Gross-Pitaevskii Regime and Beyond

Morris Brooks
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Abstract

We present a novel approach to the Bogoliubov theory of dilute Bose gases, allowing for an elementary derivation of the celebrated Lee-Huang-Yang formula in the Gross-Pitaevskii regime. Furthermore, we identify the low lying excitation spectrum beyond the Gross-Pitaevskii scaling, extending a recent result [3] to significantly more singular scaling regimes. Finally, we provide an upper bound on the ground state energy in the Gross-Pitaevskii regime that captures the correct expected order of magnitude beyond the Lee-Huang-Yang formula.

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Morris Brooks. 2023-10-17. Diagonalizing Bose Gases in the Gross-Pitaevskii Regime and Beyond. https://arxiv.org/abs/2310.11347

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