### A note on directed polymers in gaussian environments

**Yueyun Hu**

*(Université Paris XIII)*

**Qi-Man Shao**

*(The Hong Kong University of Science and Technology)*

#### Abstract

We study the problem of directed polymers in gaussian environments in $\mathbb{Z}^d$ from the viewpoint of a gaussian family indexed by the set of random walk paths. In the zero-temperature case, we give a numerical bound on the maximum of the Hamiltonian, whereas in the finite temperature case, we establish an equivalence between the "very strong disorder" and the growth rate of the entropy associated to the model

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Pages: 518-528

Publication Date: September 24, 2009

DOI: 10.1214/ECP.v14-1509

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