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arXiv · 2503.16101

Complex oscillations of non-definite Sturm-Liouville problems, II

Angelo B. Mingarelli
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Abstract

We correct and update a result of R.G.D. Richardson [13] dealing with the separation of zeros of the real and imaginary parts of non-real eigenfunctions of non-definite Sturm-Liouville eigenvalue problems. We then extend it to the case where the weight function is allowed to be identically zero on a subinterval that excludes the end-points and study the behavior of the zeros of the real and imaginary parts when the end-points are included. Examples are given illustrating the sharpness of the results along with open questions.

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Angelo B. Mingarelli. 2025-03-20. Complex oscillations of non-definite Sturm-Liouville problems, II. https://arxiv.org/abs/2503.16101

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