• Corpus ID: 235352570

Many-body excitations in trapped Bose gas: A non-Hermitian view

  title={Many-body excitations in trapped Bose gas: A non-Hermitian view},
  author={Manoussos G. Grillakis and Dionisios Margetis and Stephen Sorokanich},
We provide the analysis of a physically motivated model for a trapped dilute Bose gas with repulsive pairwise atomic interactions at zero temperature. Our goal is to describe aspects of the excited many-body quantum states by accounting for the scattering of atoms in pairs from the macroscopic state (condensate). We formally construct a many-body Hamiltonian, Happ, that is quadratic in the Boson field operators for noncondensate atoms. This Happ conserves the total number of atoms. Inspired by… 

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