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Quantum Zeno subspaces and dynamical superselection rules

P. Facchi·S. Pascazio
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Abstract

The quantum Zeno evolution of a quantum system takes place in a proper subspace of the total Hilbert space. The physical and mathematical features of the "Zeno subspaces" depend on the measuring apparatus: when this is included in the quantum description, the Zeno effect becomes a mere consequence of the dynamics and, remarkably, can be cast in terms of an adiabatic theorem, with a dynamical superselection rule. We look at several examples and focus on quantum computation and decoherence-free subspaces.

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P. Facchi, S. Pascazio. 2002-07-04. Quantum Zeno subspaces and dynamical superselection rules. https://doi.org/10.1142/9789812704634_0015

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