Page 1 Next

Displaying 1 – 20 of 34

Showing per page

The density of the area integral in + n + 1

Richard F. Gundy, Martin L. Silverstein (1985)

Annales de l'institut Fourier

Let u ( x , y ) be a harmonic function in the half-plane R + n + 1 , n 2 . We define a family of functionals D ( u ; r ) , - > r > , that are analogs of the family of local times associated to the process u ( x t , y t ) where ( x t , y t ) is Brownian motion in R + n + 1 . We show that D ( u ) = sup r D ( u ; r ) is bounded in L p if and only if u ( x , y ) belongs to H p , an equivalence already proved by Barlow and Yor for the supremum of the local times. Our proof relies on the theory of singular integrals due to Caldéron and Zygmund, rather than the stochastic calculus.

The level crossing problem in semi-classical analysis I. The symmetric case

Yves Colin de Verdière (2003)

Annales de l’institut Fourier

We describe a microlocal normal form for a symmetric system of pseudo-differential equations whose principal symbol is a real symmetric matrix with a generic crossing of eigenvalues. We use it in order to give a precise description of the microlocal solutions.

The level crossing problem in semi-classical analysis. II. The Hermitian case

Yves Colin de Verdière (2004)

Annales de l’institut Fourier

This paper is the second part of the paper ``The level crossing problem in semi-classical analysis I. The symmetric case''(Annales de l'Institut Fourier in honor of Frédéric Pham). We consider here the case where the dispersion matrix is complex Hermitian.

The signature package on Witt spaces

Pierre Albin, Éric Leichtnam, Rafe Mazzeo, Paolo Piazza (2012)

Annales scientifiques de l'École Normale Supérieure

In this paper we prove a variety of results about the signature operator on Witt spaces. First, we give a parametrix construction for the signature operator on any compact, oriented, stratified pseudomanifold X which satisfies the Witt condition. This construction, which is inductive over the ‘depth’ of the singularity, is then used to show that the signature operator is essentially self-adjoint and has discrete spectrum of finite multiplicity, so that its index—the analytic signature of  X —is well-defined....

Currently displaying 1 – 20 of 34

Page 1 Next