Hua operators, Poisson transform and relative discrete series on line bundle over bounded symmetric domains

Let $\Omega=G/K$ be a bounded symmetric domain and $S=K/L$ its Shilov boundary. We consider the action of $G$ on sections of a homogeneous line bundle over $\Omega$ and the corresponding eigenspaces of $G$-invariant differential operators. The Poisson transform maps hyperfunctions on the $S$ to the eigenspaces. We characterize the image in terms of twisted Hua operators. For some special parameters the Poisson transform is of Szeg\"o type mapping into the relative discrete series; we compute the corresponding elements in the discrete series

Jordan algebras, geometry of Hermitian symmetric spaces and non-commutative Hardy spaces

These notes were written following lectures I had the pleasure of giving on this subject at Keio University, during November and December 2004. The first part is about new applications of Jordan algebras to the geometry of Hermitian symmetric spaces and to causal semi-simple symmetric spaces of Cayley type. The second part will present new contributions for studing (non commutative) Hardy spaces of holomorphic functions on Lie semi-groups which is a part of the so called Gelfand-Gindikin program

Conformally Covariant Bi-Differential Operators on a Simple Real Jordan Algebra

For a simple real Jordan algebra $V,$ a family of bi-differential operators from $\mathcal{C}^\infty(V\times V)$ to $\mathcal{C}^\infty(V)$ is constructed. These operators are covariant under the rational action of the conformal group of $V.$ They generalize the classical {\em Rankin-Cohen} brackets (case $V=\mathbb{R}$)

The Schwarzian derivative on symmetric spaces of Cayley type

International audienceLet M be a symmetric space of Cayley type. For any conformal diffeomorphism of M we study the relationship betwenn the conformal factor of f and a generalized Schwarzian derivative of f

THE SCHWARZIAN DERIVATIVE ON SYMMETRIC SPACES OF CAYLEY TYPE

International audienceLet M be a symmetric space of Cayley type and f a conformal diffeomorphism of M. We study a relationship between the conformal factor of f and a generalized Shwarzian derivatine of f

The source operator method: an overview

This is an overview on the {source operator method} which leads to the construction of symmetry breaking differential operators (SBDO) in the context of tensor product of two principals series representations for the conformal group of a simple real Jordan algebra. This method can be applied to other geometric contexts: in the construction of SBDO for differential forms and for spinors, and also for the construction of Juhl's operators corresponding to the restriction from the sphere $S^n$ to $S^{n-1}$