Low-energy spectrum and dynamics of the weakly interacting Bose gas
نویسندگان
چکیده
We consider a gas of N bosons with interactions in the mean-field scaling regime. review proof an asymptotic expansion its low-energy spectrum, eigenstates, and dynamics, which provides corrections to Bogoliubov theory all orders 1/ N. This is based on joint works Petrat, Pickl, Seiringer, Soffer. In addition, we derive full ground state one-body reduced density matrix.
منابع مشابه
Weakly Interacting Bose Gas
We will look at the weakly interacting system at low temperatures. Already, without interactions, we have Bose condensation 〈 b+ 0 b0 〉 = N0 = N. (2) Interactions will reduce this, but if they are weak the depletion of the condensate will be a small fraction (N −N0)/N 1, or ∑ E k ′ 〈 bE k bE k 〉 N, (3) with ∑′ denoting the sum over all E k 6= 0. With the macroscopic occupation of the zero mode ...
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ژورنال
عنوان ژورنال: Journal of Mathematical Physics
سال: 2022
ISSN: ['0022-2488', '1527-2427', '1089-7658']
DOI: https://doi.org/10.1063/5.0089983