Comment on: "On the characteristic polynomial of an effective Hamiltonian"

Francisco M. Fernández

doi:10.1016/j.physleta.2022.128456

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arXiv · 2209.10112

Comment on: "On the characteristic polynomial of an effective Hamiltonian"

Francisco M. Fernández

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Abstract

We show that a method proposed recently, based on the characteristic polynomial of an effective Hamiltonian, had been developed several years earlier by other authors in a clearer and more general way. We outline both implementations of the approach and compare them by means of the calculation of the exceptional point closest to origin for a toy model.

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Francisco M. Fernández. 2022-09-19. Comment on: "On the characteristic polynomial of an effective Hamiltonian". https://doi.org/10.1016/j.physleta.2022.128456

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