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Unfolding of eigenvalue surfaces near a diabolic point due to a complex perturbation

O. N. Kirillov·A. A. Mailybaev·A. P. Seyranian
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Abstract

The paper presents a new theory of unfolding of eigenvalue surfaces of real symmetric and Hermitian matrices due to an arbitrary complex perturbation near a diabolic point. General asymptotic formulae describing deformations of a conical surface for different kinds of perturbing matrices are derived. As a physical application, singularities of the surfaces of refractive indices in crystal optics are studied.

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O. N. Kirillov, A. A. Mailybaev, A. P. Seyranian. 2004-11-02. Unfolding of eigenvalue surfaces near a diabolic point due to a complex perturbation. https://doi.org/10.1088/0305-4470/38/24/007

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