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arXiv · 2110.12155

Quantum mechanics using two auxiliary inner products

Miloslav Znojil
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Abstract

The current applications of non-Hermitian but ${\cal PT}-$symmetric Hamiltonians $H$ cover several, mutually not too closely connected subdomains of quantum physics. Mathematically, the split between the open and closed systems can be characterized by the respective triviality and non-triviality of an auxiliary inner-product metric $\Theta=\Theta(H)$. With our attention restricted to the latter, mathematically more interesting unitary-evolution case we show that the intuitive but technically decisive simplification of the theory achieved via an "additional" ${\cal PCT}-$symmetry constraint upon $H$ can be given a deeper mathematical meaning via introduction of a certain second auxiliary inner product.

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Miloslav Znojil. 2021-10-23. Quantum mechanics using two auxiliary inner products. https://doi.org/10.1016/j.physleta.2021.127792

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