3 citations · 4 across the 6 of their papers we have counts for
6 papers
Compact 4-manifolds with harmonic Weyl tensor and nonnegative biorthogonal curvature
Ezio Araujo Costa
In this note we classify compact 4-manifolds with harmonic Weyl tensor and nonnegative biorthogonal curvature
Minimal volume invariants, topological sphere theorems and biorthogonal curvature on 4-manifolds
E. Costa, E. Ribeiro
The goal of this article is to establish estimates involving the Yamabe minimal volume, mixed minimal volume and some topological invariants on compact 4-manifolds. In addition, we…
Estimates for Minimal Volume and Minimal Curvature on 4-dimensional compact manifolds
E. Costa, R. Diógenes, E. Ribeiro
In a remarkable article published in 1982, M. Gromov introduced the concept of minimal volume, namely, the minimal volume of a manifold is defined to be the greatest lower bo…
The scalar curvature and the biorthogonal curvature: A pinching problem
Ezio Araujo Costa
The famous pinching problem says that on a compact simply connected -manifold if its sectional curvature satisfies , then the manifold is homeomorphi…
A modified Yamabe invariant and a Hopf conjecture
Ezio Araujo Costa
In this paper we define the bi-orthogonal sectional curvature and we present two modified Yamabe invariants for compact 4-dimensional manifolds. In particular we obtained a relatio…
Einstein Hermitian Metrics of Non Negative Sectional Curvature
Ezio Costa
We prove that a simpy connected Hermitian Einstein 4-manifold with non-negative sectional curvature is isometric to complex projective space with the Fub…