4 papers
Log-Concavity and Level-Set Horoconvexity of the First Eigenfunction on Horoconvex Domains in the Hyperbolic Plane
Xianzhe Dai, John M. Ennis, Xuan Hien Nguyen +1
The paper proves that the first Dirichlet eigenfunction on any bounded smooth horoconvex domain in the hyperbolic plane is log‑concave, i.e., the Hessian of its negative logarithm…
A Large-Diameter Fundamental-Gap Lower Bound for Horoconvex Domains
Xianzhe Dai, John Ennis, Xuan Hien Nguyen +1
We prove a large-diameter fundamental-gap lower bound for compact horoconvex domains in real hyperbolic space of curvature \(-1\). The geometric part reduces large horoconvex domai…
Regularity of solutions to degenerate and singular free boundary problems with volume constraint
T. M. Nascimento, X. H. Nguyen, P. R. Stinga
We prove existence and regularity of solutions to degenerate and singular elliptic free boundary problems, where the volume of the positivity set of the solution is prescribed.
Constant potentials do not minimise the fundamental gap on convex domains in hyperbolic space
Julie Clutterbuck, Frieder Jäckel, Xuan Hien Nguyen
We show that for every and there exist a convex domain with diameter and a convex potential on such that the fundamental g…