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arXiv · 1212.3816

Tail decay for the distribution of the endpoint of a directed polymer

Thomas Bothner·Karl Liechty
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Abstract

We obtain an asymptotic expansion for the tails of the random variable $\tcal=\arg\max_{u\in\mathbb{R}}(\mathcal{A}_2(u)-u^2)$ where $\mathcal{A}_2$ is the Airy$_2$ process. Using the formula of Schehr \cite{Sch} that connects the density function of $\tcal$ to the Hastings-McLeod solution of the second Painlevé equation, we prove that as $t\rightarrow\infty$, $\mathbb{P}(|\tcal|>t)=Ce^{-4/3φ(t)}t^{-145/32}(1+O(t^{-3/4}))$, where $φ(t)=t^3-2t^{3/2}+3t^{3/4}$, and the constant $C$ is given explicitly.

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Thomas Bothner, Karl Liechty. 2013-01-04. Tail decay for the distribution of the endpoint of a directed polymer. https://doi.org/10.1088/0951-7715%2F26%2F5%2F1449

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