activity
19992026
most citedA lower bound to the spectral threshold in curved tubes

43 citations · 106 across the 34 of their papers we have counts for

collaborators

47 papers

math.SP2026

Spherical n-lunes: billiards and eigenvalues

Pedro Freitas, Isabel Salavessa

We characterise the periodic orbits of geodesic billiards on spherical lunes on . In the case of angle openings of the form for positive integer we fully…

math.SP2024★ 2 cited

Recurrence formulae for spectral determinants

J. Cunha, P. Freitas

We develop a unified method to study spectral determinants for several different manifolds, including spheres and hemispheres, and projective spaces. This is a direct consequence o…

math.SP2023★ 1 cited

On domain monotonicity of Neumann eigenvalues of convex domains

Pedro Freitas, James B. Kennedy

Inspired by a recent result of Funano's, we provide a sharp quantitative comparison result between the first nontrivial eigenvalues of the Neumann Laplacian on bounded convex domai…

math.SP2022★ 5 cited

Families of non-tiling domains satisfying Pólya's conjecture

Pedro Freitas, Isabel Salavessa

We show the existence of classes of non-tiling domains satisfying Pólya's conjecture in any dimension, in both the Euclidean and non-Euclidean cases. This is a consequence of a mor…

math.SP2022★ 1 cited

Pólya-type inequalities on spheres and hemispheres

Pedro Freitas, Jing Mao, Isabel Salavessa

Given an eigenvalue of the Laplace-Beltrami operator on spheres or hemispheres, with multiplicity such that , we characterise the lowest a…

math.HO2021

The Golden Angle is not Constructible

Pedro J. Freitas

We prove that the golden angle (an angle that divides the circle in the golden ratio) is not constructible using straightedge and compass.