collaborators

6 papers

math.AP2026

Structure of the free interfaces near triple junction singularities in harmonic maps and optimal partition problems

Roberto Ognibene, Bozhidar Velichkov

We consider energy-minimizing harmonic maps into trees and we prove the regularity of the singular part of the free interface near triple junction points. Precisely, by proving a n…

math.AP2026

On the splitting of Neumann eigenvalues in perforated domains

Veronica Felli, Lorenzo Liverani, Roberto Ognibene

We address the problem of splitting of eigenvalues of the Neumann Laplacian under singular domain perturbations. We consider a domain perturbed by the excision of a small spherical…

math.AP2025

A survey on the optimal partition problem

Roberto Ognibene, Bozhidar Velichkov

This survey synthesizes the current state of the art on the regularity theory for solutions to the optimal partition problem. Namely, we consider non-negative, vector-valued Sobole…

math.AP2025

On asymptotics of Robin eigenvalues in the Dirichlet limit

Roberto Ognibene

We investigate the asymptotic behavior of the eigenvalues of the Laplacian with homogeneous Robin boundary conditions, when the (positive) Robin parameter is diverging. In this fra…

math.AP2025

Asymptotics of nonlinear Robin energies

Giuseppe Buttazzo, Roberto Ognibene

This paper investigates the asymptotic behavior of a class of nonlinear variational problems with Robin-type boundary conditions on a bounded Lipschitz domain. The energy functiona…

math.AP2025

Quantitative spectral stability for the Neumann Laplacian in domains with small holes

Veronica Felli, Lorenzo Liverani, Roberto Ognibene

The aim of the present paper is to investigate the behavior of the spectrum of the Neumann Laplacian in domains with little holes excised from the interior. More precisely, we cons…