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Robustness of Wave Functions of Interacting Many Bosons in a Leaky Box

Akira Shimizu·Takayuki Miyadera
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Abstract

We study the robustness, against the leakage of bosons, of wave functions of interacting many bosons confined in a finite box, by deriving and analyzing a general equation of motion for the reduced density operator. We identify a robust wave function that remains a pure state, whereas other wave functions, such as the Bogoliubov's ground state and the ground state with a fixed number of bosons, evolve into mixed states. Although these states all have the off-diagonal long-range order, and almost the same energy densities, we argue that only the robust state is realized as a macroscopic quantum state.

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Akira Shimizu, Takayuki Miyadera. 2001-03-14. Robustness of Wave Functions of Interacting Many Bosons in a Leaky Box. https://doi.org/10.1103/physrevlett.85.688

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