Displaying 221 – 240 of 467

Showing per page

The null condition and global existence for nonlinear wave equations on slowly rotating Kerr spacetimes

Jonathan Luk (2013)

Journal of the European Mathematical Society

We study a semilinear equation with derivatives satisfying a null condition on slowly rotating Kerr spacetimes. We prove that given sufficiently small initial data, the solution exists globally in time and decays with a quantitative rate to the trivial solution. The proof uses the robust vector field method. It makes use of the decay properties of the linear wave equation on Kerr spacetime, in particular the improved decay rates in the region { r t 4 } .

The polar curve of a foliation on 2

Rogério S. Mol (2010)

Annales de la faculté des sciences de Toulouse Mathématiques

We study some properties of the polar curve P l associated to a singular holomorphic foliation on the complex projective plane 2 . We prove that, for a generic center l 2 , the curve P l is irreducible and its singular points are exactly the singular points of with vanishing linear part. We also obtain upper bounds for the algebraic multiplicities of the singularities of and for its number of radial singularities.

The proportionality constant for the simplicial volume of locally symmetric spaces

Michelle Bucher-Karlsson (2008)

Colloquium Mathematicae

We follow ideas going back to Gromov's seminal article [Publ. Math. IHES 56 (1982)] to show that the proportionality constant relating the simplicial volume and the volume of a closed, oriented, locally symmetric space M = Γ∖G/K of noncompact type is equal to the Gromov norm of the volume form in the continuous cohomology of G. The proportionality constant thus becomes easier to compute. Furthermore, this method also gives a simple proof of the proportionality principle for arbitrary manifolds.

Currently displaying 221 – 240 of 467