activity
20162024
most citedGeography of pinched four-manifolds

1 citations · 1 across the 3 of their papers we have counts for

collaborators

13 papers

math.AG2024

Two results on the Convex Algebraic Geometry of sets with continuous symmetries

Renato G. Bettiol, Mario Kummer, Ricardo A. E. Mendes

We prove two results on convex subsets of Euclidean spaces invariant under an orthogonal group action. First, we show that invariant spectrahedra admit an equivariant spectrahedral…

math.MG2022

A geometric take on Kostant's Convexity Theorem

Ricardo A. E. Mendes

Given a compact Lie group and an orthogonal -representation , we give a purely metric criterion for a closed subset of the orbit space to have convex pre-image in $…

math.DG2021★ 1 cited

Geography of pinched four-manifolds

Renato G. Bettiol, Mario Kummer, Ricardo A. E. Mendes

We prove several new restrictions on the Euler characteristic and signature of oriented 4-manifolds with (positively or negatively) pinched sectional curvature. In particular, we s…

math.RT2020

Maximality of Laplacian Algebras, with Applications to Invariant Theory

Ricardo A. E. Mendes, Marco Radeschi

We show Laplacian algebras are maximal, and give applications to the Classical Invariant Theory of real orthogonal representations of compact groups, including: The solution of the…

math.MG2020

Lifting isometries of orbit spaces

Ricardo A. E. Mendes

Given an orthogonal representation of a compact group, we show that any element of the connected component of the isometry group of the orbit space lifts to an equivariant isometry…

math.DG2019

Laplacian algebras, manifold submetries and the Inverse Invariant Theory Problem

Ricardo A. E. Mendes, Marco Radeschi

Manifold submetries of the round sphere are a class of partitions of the round sphere that generalizes both singular Riemannian foliations, and the orbit decompositions by the orth…