Coarse graining, fractional moments and the critical slope of random copolymers

Fabio Lucio Toninelli (CNRS and ENS Lyon)

Abstract


For a much-studied model of random copolymer at a selective interface we prove that the slope of the critical curve in the weak-disorder limit is strictly smaller than 1, which is the value given by the annealed inequality. The proof is based on a coarse-graining procedure, combined with upper bounds on the fractional moments of the partition function.

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Pages: 531-547

Publication Date: February 23, 2009

DOI: 10.1214/EJP.v14-612

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