Morphology of an interacting three-dimensional trapped Bose-Einstein condensate from many-particle variance anisotropy

Ofir E. Alon

doi:10.3390/sym13071237

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arXiv · 2106.07001

Morphology of an interacting three-dimensional trapped Bose-Einstein condensate from many-particle variance anisotropy

Ofir E. Alon

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Abstract

The variance of the position operator is associated with how wide or narrow a wave-packet is, the momentum variance is similarly correlated with the size of a wave-packet in momentum space, and the angular-momentum variance quantifies to what extent a wave-packet is non-spherically symmetric. We examine an interacting three-dimensional trapped Bose-Einstein condensate at the limit of an infinite number of particles, and investigate its position, momentum, and angular-momentum anisotropies. Computing the variances of the three Cartesian components of the position, momentum, and angular-momentum operators we present simple scenarios where the anisotropy of a Bose-Einstein condensate is different at the many-body and mean-field levels of theory, despite having the same many-body and mean-field densities per particle. This suggests a way to classify correlations via the morphology of 100\% condensed bosons in a three-dimensional trap at the limit of an infinite number of particles. Implications are briefly discussed.

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Ofir E. Alon. 2021-06-13. Morphology of an interacting three-dimensional trapped Bose-Einstein condensate from many-particle variance anisotropy. https://doi.org/10.3390/sym13071237

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