collaborators

5 papers

math.DS2026

Monotonicity of the Liouville entropy along the Ricci flow on surfaces

Karen Butt, Alena Erchenko, Tristan Humbert +1

We show that the Liouville entropy of the geodesic flow of a closed surface of non-constant negative curvature is eventually strictly increasing along the normalized Ricci flow (NR…

math.SP2026

Flexibility of eigenvalues for graph Laplacians arising from genus 3 surfaces

Alena Erchenko, Dmitry Jakobson, Allison Tsypin

It is known that the small eigenvalues of the Laplacian of a Riemann surface close to the boundary of the modular space can be well approximated by the eigenvalues of the discrete…

math.DS2025

Normal forms in a neighborhood of hyperbolic periodic orbits for flows in dimension 3

Alena Erchenko, Kurt Vinhage, Yun Yang

In a neighborhood of a hyperbolic periodic orbit of a volume-preserving flow on a manifold of dimension 3, we define and show the existence of a normal form for the generator of th…

math.DG2025

Marked Poincaré rigidity near hyperbolic metrics and injectivity of the Lichnerowicz Laplacian in dimension 3

Karen Butt, Alena Erchenko, Tristan Humbert +2

Let be a compact manifold without boundary equipped with a Riemannian metric of negative curvature. In this paper, we introduce the marked Poincaré determinant (MPD), a ho…

math.DG2025

Monotonicity of topological entropy along the Ricci flow near a hyperbolic metric

Karen Butt, Alena Erchenko, Tristan Humbert

In 2004, Manning showed that the topological entropy of the geodesic flow of a closed surface of non-constant negative curvature is strictly decreasing along the normalized Ricci f…