Sharp asymptotics for the partition function of some continuous-time directed polymers
نویسندگان
چکیده
This paper is concerned with two related types of directed polymers in a random medium. The first one is a d-dimensional Brownian motion living in a random environment which is Brownian in time and homogeneous in space. The second is a continuous-time random walk on Zd, in a random environment with similar properties as in continuous space, albeit defined only on R+ ×Zd. The case of a space-time white noise environment can be acheived in this second setting. By means of some Gaussian tools, we estimate the free energy of these models at low temperature, and give some further information on the strong disorder regime of the objects under consideration.
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تاریخ انتشار 2007