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Borcea’s Variance Conjectures on the Critical Points of Polynomials

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Notions of Positivity and the Geometry of Polynomials

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Abstract

Closely following recent ideas of J. Borcea, we discuss various modifications and relaxations of Sendov’s conjecture about the location of critical points of a polynomial with complex coefficients. The resulting open problems are formulated in terms of matrix theory, mathematical statistics or potential theory. Quite a few links between classical works in the geometry of polynomials and recent advances in the location of spectra of small rank perturbations of structured matrices are established. A couple of simple examples provide natural and sometimes sharp bounds for the proposed conjectures.

Mathematics Subject Classification (2000). Primary 12D10; Secondary 26C10, 30C10, 15A42, 15B05.

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Correspondence to Dmitry Khavinson .

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Khavinson, D., Pereira, R., Putinar, M., Saff, E.B., Shimorin, S. (2011). Borcea’s Variance Conjectures on the Critical Points of Polynomials. In: Brändén, P., Passare, M., Putinar, M. (eds) Notions of Positivity and the Geometry of Polynomials. Trends in Mathematics. Springer, Basel. https://doi.org/10.1007/978-3-0348-0142-3_16

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