PT-Symmetric Models in Curved Manifolds

The collision of two real eigenvalues (balls) results in the creation of complex conjugated pair of eigenvalues. The restoration of two real eigenvalues from the complex conjugated pair follows and the next collision produces another complex conjugated pair. The coupling parameter plays the role of "time".

The details can be found in PT-symmetric models in curved manifolds or arXiv:1001.2988 by D. Krejčiřík and P. Siegl.