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Berry phase due to quantum measurements

P. Facchi·S. Pascazio
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Abstract

The usual, "static" version of the quantum Zeno effect consists in the hindrance of the evolution of a quantum systems due to repeated measurements. There is however a "dynamic" version of the same phenomenon, first discussed by von Neumann in 1932 and subsequently explored by Aharonov and Anandan, in which a system is forced to follow a given trajectory. A Berry phase appears if such a trajectory is a closed loop in the projective Hilbert space. A specific example involving neutron spin is considered and a similar situation with photon polarization is investigated.

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P. Facchi, S. Pascazio. 1999-04-24. Berry phase due to quantum measurements. https://arxiv.org/abs/quant-ph/9904082

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