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arXiv · 0806.0365

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

F. Toninelli
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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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F. Toninelli. 2009-02-25. Coarse graining, fractional moments and the critical slope of random copolymers. https://arxiv.org/abs/0806.0365

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