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arXiv · 1304.6227

The tacnode Riemann-Hilbert problem

Arno Kuijlaars
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Abstract

The tacnode Riemann-Hilbert problem is a 4 x 4 matrix valued RH problem that appears in the description of the local behavior of two touching groups of non-intersecting Brownian motions. The same RH problem was also found by Duits and Geudens to describe a new critical regime in the two-matrix model. Delvaux gave integral representations for some of the entries of the 4 x 4 matrix. We complement this work by presenting integral representations for all of the entries. As a consequence we give an explicit formula for the Duits-Geudens critical kernel.

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Arno Kuijlaars. 2013-04-23. The tacnode Riemann-Hilbert problem. https://arxiv.org/abs/1304.6227

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