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arXiv · 1103.4001

The horizons of observability in PT-symmetric four-site quantum lattices

Miloslav Znojil
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Abstract

The "Hermitizability" problem of quantum theory is explained, discussed and illustrated via the discrete-lattice cryptohermitian quantum graphs. In detail, the description of the domain ${\cal D}$ of admissible parameters is provided for the "circular-model" three-parametric quantum Hamiltonian $H$ using periodic boundary conditions. It is emphasized that even in such an elementary system the weak- and strong-coupling subdomains of ${\cal D}$ become, unexpectedly, non-empty and disconnected.

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Miloslav Znojil. 2011-03-21. The horizons of observability in PT-symmetric four-site quantum lattices. https://arxiv.org/abs/1103.4001

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