Spontaneous breakdown of PT symmetry in the solvable square-well model

  title={Spontaneous breakdown of PT symmetry in the solvable square-well model},
  author={Miloslav Znojil and G{\'e}za L{\'e}vai},
  journal={arXiv: High Energy Physics - Theory},
In many PT symmetric models with real spectra, apparently, energy levels "merge and disappear" at a point of the spontaneous PT-symmetry breaking. We argue that such an oversimplified and discontinuous physical interpretation of this mechanism as proposed, e.g., by one of us in Phys. Lett. A 285 (2001), p. 7 would be inappropriate. Using the elementary square-well model of the above reference in the strongly non-Hermitian regime we exemplify how the doublets of states with broken PT symmetry… 

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