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arXiv · 2307.16805

Poincaré symmetries and representations in pseudo-Hermitian quantum field theory

Esra Sablevice·Peter Millington
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Abstract

This paper explores quantum field theories with pseudo-Hermitian Hamiltonians, where PT-symmetric Hamiltonians serve as a special case. In specific regimes, these pseudo-Hermitian Hamiltonians have real eigenspectra, orthogonal eigenstates, and unitary time evolution. So far, most pseudo-Hermitian quantum field theories have been constructed using analytic continuation or by adding non-Hermitian terms to otherwise Hermitian Hamiltonians. However, in this paper, we take a different approach. We construct pseudo-Hermitian scalar and fermionic quantum field theories from first principles by extending the Poincaré algebra to include non-Hermitian generators. This allows us to develop consistent pseudo-Hermitian quantum field theories, with Lagrangian densities that transform appropriately under the proper Poincaré group. By doing so, we establish a more solid theoretical foundation for the emerging field of non-Hermitian quantum field theory.

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Esra Sablevice, Peter Millington. 2024-04-03. Poincaré symmetries and representations in pseudo-Hermitian quantum field theory. https://doi.org/10.1103/physrevd.109.065012

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