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arXiv · 1002.3347

Double scaling limits of random matrices and minimal (2m,1) models: the merging of two cuts in a degenerate case

Olivier Marchal·Mattia Cafasso
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Abstract

In this article, we show that the double scaling limit correlation functions of a random matrix model when two cuts merge with degeneracy $2m$ (i.e. when $y\sim x^{2m}$ for arbitrary values of the integer $m$) are the same as the determinantal formulae defined by conformal $(2m,1)$ models. Our approach follows the one developed by Bergère and Eynard in \cite{BergereEynard} and uses a Lax pair representation of the conformal $(2m,1)$ models (giving Painlevé II integrable hierarchy) as suggested by Bleher and Eynard in \cite{BleherEynard}. In particular we define Baker-Akhiezer functions associated to the Lax pair to construct a kernel which is then used to compute determinantal formulae giving the correlation functions of the double scaling limit of a matrix model near the merging of two cuts.

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Olivier Marchal, Mattia Cafasso. 2011-03-24. Double scaling limits of random matrices and minimal (2m,1) models: the merging of two cuts in a degenerate case. https://doi.org/10.1088/1742-5468%2F2011%2F04%2Fp04013

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