Zobrazeno 1 - 10
of 12
pro vyhledávání: '"Marcus Kriele"'
Autor:
Marcus Kriele
Publikováno v:
Journal of Geometry. 66:123-135
We investigate the conormal geometry of relative affine hypersurfaces whose relative metric (Blaschke metric) degenerates on a codimension 1 submanifold. Such hypersurfaces arise in the investigation of compact hypersurfaces which are not diffeomorph
Autor:
Marcus Kriele, Luc Vrancken
Publikováno v:
Transactions of the American Mathematical Society. 352:1581-1599
We study ane hyperspheres M with constant sectional curvature (with respect to the ane metric h). A conjecture by M. Magid and P. Ryan states that every such ane hypersphere with nonzero Pick invariant is anely equivalent to either where the dimensio
Autor:
Luc Vrancken, Marcus Kriele
Publikováno v:
Archiv der Mathematik. 72:223-232
We study Lagrangian immersions \(M^n_1\) into Lorentzian complex indefinite space forms \(\tilde M^n_1(4 \tilde c), \tilde c \ne 0\) and classify all such immersions which are minimal and have constant curvature \(c \ne \tilde c\).
Autor:
Luc Vrancken, Marcus Kriele
Publikováno v:
Geometriae Dedicata. 77:239-252
In analogy to an inequality of Chen [2], Scharlach and co-workers [7] have found a new, optimal inequality for (equi-) affine spheres. We classify those three-dimensional hyperbolic affine spheres for which the corresponding equality is assumed. This
Autor:
Marcus Kriele, Marek Kossowski
Publikováno v:
Geometriae Dedicata. 64:1-16
Consider a smooth manifold with smooth (0, 2)-tensor which changes bilinear type on a hypersurface. We show that there are natural tensors on this hypersurface which control the smooth extension of sectional, Ricci, and scalar curvature. This enables
Publikováno v:
Classical and Quantum Gravity. 13:1161-1182
In a four-dimensional Lorentzian manifold, a family of light rays emanating orthogonally from a spacelike 2-surface generates a `wavefront'. The caustic of a wavefront is the set of all points where the wavefront fails to be an (immersed) submanifold
Publikováno v:
Nonlinearity. 9:209-224
We establish the local existence of solutions with isolated -singularities for smooth, possibly underdetermined, systems of first-order ODE. AMS classification scheme numbers 34A34, 34C05
Autor:
Marcus Kriele, Giselle Lim
Publikováno v:
Classical and Quantum Gravity. 12:3019-3035
We study a class of singularities of prescribed behaviour and investigate physical properties such as their strength, and the validity of energy conditions in a neighbourhood of these singularities. As applications of our theory, we show that shell (
Publikováno v:
Results in Mathematics. 27:41-50
Local and global properties of the first order spherical functions are generalized to projectively flat manifolds.
Autor:
Marcus Kriele, Marek Kossowski
Publikováno v:
Proceedings of the Royal Society of London. Series A: Mathematical and Physical Sciences. 446:115-126
We give a local existence and uniqueness theorem for solutions of Einstein’s equations with dust energy momentum tensor in the class of m -dimensional, analytic, transverse, signature type changing spacetimes where the initial conditions are give