# Three Solvable Matrix Models of a Quantum Catastrophe

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## Abstract

Three classes of finite-dimensional models of quantum systems exhibiting spectral degeneracies called quantum catastrophes are described in detail. Computer-assisted symbolic manipulation techniques are shown unexpectedly efficient for the purpose.

## Keywords

Quantum theory PT symmetry Finite-dimensional non-Hermitian Hamiltonians Exceptional-point localization Quantum theory of catastrophes Methods of computer algebra## References

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