RT Journal Article T1 Phase transitions in multi-cut matrix models and matched solutions of Whitham hierarchies A1 Álvarez Galindo, Gabriel A1 Martínez Alonso, Luis A1 Medina Reus, Elena AB We present a method for studying phase transitions in the large N limit of matrix models using matched solutions of Whitham hierarchies. The endpoints of the eigenvalue spectrum as functions of the temperature are characterized both as solutions of hodograph equations and as solutions of a system of ordinary differential equations. In particular we show that the free energy of the matrix model is the quasiclassical tau-function of the associated hierarchy, and that critical processes in which the number of cuts changes in one unit are third-order phase transitions described by C(1) matched solutions of Whitham hierarchies. The method is illustrated with the Bleher-Eynard model for the merging of two cuts. We show that this model involves also the birth of a cut. PB IOP Publishing SN 1742-5468 YR 2010 FD 2010-03 LK https://hdl.handle.net/20.500.14352/43721 UL https://hdl.handle.net/20.500.14352/43721 LA eng NO �© 2010 IOP Publishing Ltd and SISSA. The financial support of the Universidad Complutense under project GR58/08-910556, that of the Comision Interministerial de Ciencia y Tecnologia under projects FIS2008-00200 and FIS2008-00209, and that of the ESF programme MISGAM are gratefully acknowledged. NO Universidad Complutense NO Comisión Interministerial de Ciencia y Tecnología NO ESF programme MISGAM. DS Docta Complutense RD 6 abr 2025