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P,T,PT, and CPT invariance of Hermitian Hamiltonians

Zafar Ahmed
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Abstract

Currently, it has been claimed that certain Hermitian Hamiltonians have parity (P) and they are PT-invariant. We propose generalized definitions of time-reversal operator (T) and orthonormality such that all Hermitian Hamiltonians are P, T, PT, and CPT invariant. The PT-norm and CPT-norm are indefinite and definite respectively. The energy-eigenstates are either E-type (e.g., even) or O-type (e.g., odd). C mimics the charge-conjugation symmetry which is recently found to exist for a non-Hermitian Hamiltonian. For a Hermitian Hamiltonian it coincides with P.

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Zafar Ahmed. 2003-02-26. P,T,PT, and CPT invariance of Hermitian Hamiltonians. https://doi.org/10.1016/s0375-9601(03)00339-6

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