Université de Fribourg

Arc and curve graphs for infinite-type surfaces

Aramayona, Javier ; Fossas, Ariadna ; Parlier, Hugo

In: Proceedings of the American Mathematical Society, 2017, vol. 145, no. 11, p. 4995–5006

We study arc graphs and curve graphs for surfaces of infinite topological type. First, we define an arc graph relative to a finite number of (isolated) punctures and prove that it is a connected, uniformly hyperbolic graph of infinite diameter; this extends a recent result of J. Bavard to a large class of punctured surfaces.

Université de Fribourg

Convexity of strata in diagonal pants graphs of surfaces

Aramayona, Javier ; Lecuire, Cyril ; Parlier, Hugo ; Shackleton, Kenneth J.

In: Publicacions Matemàtiques, 2012, vol. 57, no. 1, p. 219-237

We prove a number of convexity results for strata of the diagonal pants graph of a surface, in analogy with the extrinsic geometric properties of strata in the Weil-Petersson completion. As a consequence, we exhibit convex flat subgraphs of every possible rank inside the diagonal pants graph.