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arXiv · 1403.3639

Toeplitz determinants with merging singularities

T. Claeys·I. Krasovsky
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Abstract

We study asymptotic behavior for determinants of $n\times n$ Toeplitz matrices corresponding to symbols with two Fisher-Hartwig singularities at the distance $2t\ge0$ from each other on the unit circle. We obtain large $n$ asymptotics which are uniform for $0<t<t_0$ where $t_0$ is fixed. They describe the transition as $t\to 0$ between the asymptotic regimes of 2 singularities and 1 singularity. The asymptotics involve a particular solution to the Painlev\'e V equation. We obtain small and large argument expansions of this solution. As applications of our results we prove a conjecture of Dyson on the largest occupation number in the ground state of a one-dimensional Bose gas, and a conjecture of Fyodorov and Keating on the second moment of powers of the characteristic polynomials of random matrices.

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T. Claeys, I. Krasovsky. 2014-03-14. Toeplitz determinants with merging singularities. https://doi.org/10.1215/00127094-3164897

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