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Classical phase space structure induced by spontaneous symmetry breaking

M. Grigorescu
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Abstract

The collective dynamics of a many-body system is described as a special case of low-energy quantum dynamics, occurring when the ground state breaks a continuous symmetry of the Hamiltonian. This approach is applied to the spontaneous breaking of the rotational symmetry of a nuclear Hamiltonian. It is shown that the excitation operator of the isovector low-lying angular oscillations in deformed nuclei is a linear combination between angular momentum operators, which generate static rotations, and "angle" operators, which generate the transition to a rotating frame.

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M. Grigorescu. 2000-04-30. Classical phase space structure induced by spontaneous symmetry breaking. https://arxiv.org/abs/math-ph/0005001

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