Injectivité de la transformation de Radon sur les grassmanniennes
Injectivity radius and low eigenvalues of hyperbolic manifolds.
Injectivity radius and optimal regularity of Lorentzian manifolds with bounded curvature
We review recent work on the local geometry and optimal regularity of Lorentzian manifolds with bounded curvature. Our main results provide an estimate of the injectivity radius of an observer, and a local canonical foliations by CMC (Constant Mean Curvature) hypersurfaces, together with spatially harmonic coordinates. In contrast with earlier results based on a global bound for derivatives of the curvature, our method requires only a sup-norm bound on the curvature near the given observer.
Instabile Minimalflächen in Riemannschen Mannigfaltigkeiten nichtpositver Schnittkrümmung.
Instability of constant mean curvature surfaces of revolution in spherically symmetric spaces.
Instability of the nearly-Kähler six-sphere.
Instanton invariants of ...P2 via topology.
Instantons on cylindrical manifolds and stable bundles.
Instantons on Hopf surfaces and monopoles on solid tori.
Instantony a topologie čtyřrozměrných variet
Integrability for representations appearing in geometric pre-quantization
Integrability obstructions for extensions of Lie algebroids
Integrability of distribution on a nearly Sasakian manifold.
Integrability of tensor structures of electromagnetic type.
Integrable equations and their evolutions based on intrinsic geometry of Riemann spaces.
Integrable smooth planar billiards and evolutes.
Integral distance on a Lipschitz Riemannian manifold.
Integral formula for secantoptics and its application
Some properties of secantoptics of ovals defined by Skrzypiec in 2008 were proved by Mozgawa and Skrzypiec in 2009. In this paper we generalize to this case results obtained by Cieślak, Miernowski and Mozgawa in 1996 and derive an integral formula for an annulus bounded by a given oval and its secantoptic. We describe the change of the area bounded by a secantoptic and find the differential equation for this function. We finish with some examples illustrating the above results.
Integral formulae for a Riemannian manifold with two orthogonal distributions
We obtain a series of new integral formulae for a distribution of arbitrary codimension (and its orthogonal complement) given on a closed Riemannian manifold, which start from the formula by Walczak (1990) and generalize ones for foliations by several authors. For foliations on space forms our formulae reduce to the classical type formulae by Brito-Langevin-Rosenberg (1981) and Brito-Naveira (2000). The integral formulae involve the conullity tensor of a distribution, and certain components of the...
Integral formulas for closed spacelike hypersurfaces in anti-de Sitter space
In this paper, we study closed -maximal spacelike hypersurfaces in anti-de Sitter space with two distinct principal curvatures and give some integral formulas about these hypersurfaces.