A new symmetry theory for non-Hermitian Hamiltonians

Abstract: The {\eta} pseudo PT symmetry theory, denoted by the symbol {\eta}, explores the conditions under which non-Hermitian Hamiltonians can possess real spectra despite the violation of PT symmetry, that is the adjoint of H, denoted H^{{\dag}} is expressed as H^{{\dag}}=PTHPT. This theory introduces a new symmetry operator, {\eta}=PT{\eta}, which acts on the Hilbert space. The {\eta} pseudo PT symmetry condition requires the Hamiltonian to commute with the {\eta} operator, leading to real eigenvalues. We discuss some general implications of our results for the coupled non hermitian harmonic oscillator.