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arXiv · 1411.6648

Entropy from Scaling Symmetry Breaking

Neymar Cavalcante·Saulo Diles·Kumar S. Gupta·Amilcar R. de Queiroz
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Abstract

The scaling symmetry in conformal quantum mechanics (CQM) can be broken due to the boundary conditions that follow from the requirement of a unitary time evolution of the Hamiltonian. We show that the scaling symmetry of CQM can be restored by introducing a suitable mixed state, which is associated with a nonvanishing von Neumann entropy. We give an explicit formula for the entropy arising from the mixed state in CQM. Our work provides a direct link between the restoration of a broken symmetry and von Neumann entropy.

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Neymar Cavalcante, Saulo Diles, Kumar S. Gupta, Amilcar R. de Queiroz. 2014-11-24. Entropy from Scaling Symmetry Breaking. https://arxiv.org/abs/1411.6648

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