Event Detail

Event Type: 
Probability Seminar
Tuesday, November 25, 2014 - 16:00 to 17:00
Kidder 356

Speaker Info

University of Sao Paulo, Brazil

We show the presence of a first-order phase transition for a ferromagnetic Ising model on integer 2 dimensional lattice with a periodical external magnetic field. The external field takes two values h and -h, where h>0. The sites associated with positive and negative values of external field form a chessboard configuration with rectangular cells of sides L1xL2 sites. The phase transition holds if h is small enough. We prove a first-order phase transition using reflection positivity (RP) method. We apply a key inequality which is usually referred to as the chessboard estimate. This is a joint work with E. Pechersky and M. Gonzalez, my PhD student.