Airy wanderer line ensembles
Evgeni Dimitrov
TL;DR
This work develops a multi-parameter generalization of the extended Airy kernel, introducing the Airy wanderer kernel $K_{a,b,c}$ built from two convergent parameter sequences and two nonnegative shifts. It proves the existence of a determinantal point process on $\mathbb{R}^2$ with this kernel and, under the finite-minus-parameter condition ($c^-=0$ and finite $J_a^-,J_b^-$), lifts it to a line ensemble on $\mathbb{R}$ with the Brownian Gibbs property, extending the wanderer ensemble framework. The approach hinges on a careful scaling and limiting procedure for Schur processes, via geometric last passage percolation with defects, yielding a double-contour kernel that converges to $K_{a,b,c}$. The paper also develops upper-tail and tightness estimates to establish finite-dimensional convergence and constructs the corresponding Wanderer line ensembles, providing a robust probabilistic framework for these generalized integrable models within the KPZ universality class. Together, these results broaden the class of exactly solvable line ensembles and connect multi-parameter deformations of the Airy kernel to concrete probabilistic objects with Gibbsian structure.
Abstract
In (J. Stat. Phys. 132, 275-290, 2008) Borodin and Péché introduced a generalization of the extended Airy kernel based on two infinite sets of parameters. For an arbitrary choice of parameters we construct determinantal point processes on $\mathbb{R}^2$ for these generalized kernels. In addition, for a subset of the parameter space we show that the point processes can be lifted to line ensembles on $\mathbb{R}$, which satisfy the Brownian Gibbs property. Our ensembles generalize the wanderer line ensembles introduced by Corwin and Hammond in (Invent. Math. 195, 441-508, 2014).
