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arXiv · 2112.08964

Excitation spectrum for the Lee-Huang-Yang model for the bose gas in a periodic box

Stephen Sorokanich
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Abstract

We derive a new formula for excited many-body eigenstates of the approximate Hamiltonian of Lee, Huang, and Yang, which describes the weakly interacting bose gas in a periodic box. Our formula utilizes a non-Hermitian transform to isolate a process of pair excitation in all excited states. This program is inspired by the description of Wu for the many-body ground state of the Lee-Huang-Yang Hamiltonian, as well as similar descriptions for the ground state of quadratic Hamiltonians in generic trapping potentials.

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Stephen Sorokanich. 2021-12-16. Excitation spectrum for the Lee-Huang-Yang model for the bose gas in a periodic box. https://arxiv.org/abs/2112.08964

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