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arXiv · 0811.4105

Unexpected features of quantum degeneracies in a pairing model with two integrable limits

J. Dukelsky·J. Okolowicz·M. Ploszajczak
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Abstract

The evolution pattern of level crossings and exceptional points is studied in a non-integrable pairing model with two different integrable limits. One of the integrable limits has two independent parameter-dependent integrals of motion. We demonstrate, and illustrate in our model, that quantum integrability of a system with more than one parameter-dependent integral of motion is always signaled by level crossings of a complex-extended Hamiltonian. We also find that integrability implies a reduced number of exceptional points. Both properties could uniquely characterize quantum integrability in small Hilbert spaces.

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J. Dukelsky, J. Okolowicz, M. Ploszajczak. 2008-11-25. Unexpected features of quantum degeneracies in a pairing model with two integrable limits. https://arxiv.org/abs/0811.4105

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