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The C Operator in PT-Symmetric Quantum Field Theory Transforms as a Lorentz Scalar

Carl M. Bender·Sebastian F. Brandt·Jun-Hua Chen·Qinghai Wang
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Abstract

A non-Hermitian Hamiltonian has a real positive spectrum and exhibits unitary time evolution if the Hamiltonian possesses an unbroken PT (space-time reflection) symmetry. The proof of unitarity requires the construction of a linear operator called C. It is shown here that C is the complex extension of the intrinsic parity operator and that the C operator transforms under the Lorentz group as a scalar.

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Carl M. Bender, Sebastian F. Brandt, Jun-Hua Chen, Qinghai Wang. 2004-12-29. The C Operator in PT-Symmetric Quantum Field Theory Transforms as a Lorentz Scalar. https://doi.org/10.1103/physrevd.71.065010

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