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Partial Dynamical Symmetry at Critical-Points of Quantum Phase Transitions

A. Leviatan
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Abstract

We show that partial dynamical symmetries (PDS) can occur at critical-points of quantum phase transitions, in which case, underlying competing symmetries are conserved exactly by a subset of states, and mix strongly in other states. Several types of PDS are demonstrated with the example of critical-point Hamiltonians for first- and second-order transitions in the framework of the interacting boson model, whose dynamical symmetries correspond to different shape-phases in nuclei.

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A. Leviatan. 2007-06-04. Partial Dynamical Symmetry at Critical-Points of Quantum Phase Transitions. https://doi.org/10.1103/physrevlett.98.242502

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