Ornstein–Uhlenbeck semi-groups on stratified groups

On Lie Semi-Groups

a subset of real Euclidean n-space, En, by (p, q) → F (p − q) = p ◦ q. In this note we shall be concerned with a representation T (.) of π as a semi-group of bounded linear operators on a Banach space X. More particularly, we suppose that postulates P1, P2, P3, P5, and P6 of chapter 25 of (2) are satisfied so that, by Theorem 25.3.1 of that book, there is a continuous function, f(.), defined on...

Realization of a Certain Class of Semi-Groups as Value Semi-Groups of Valuations

Extremal Polynomials in Stratified Groups

We introduce a family of extremal polynomials associated with the prolongation of a stratified nilpotent Lie algebra. These polynomials are related to a new algebraic characterization of abnormal subriemannian geodesics in stratified nilpotent Lie groups. They satisfy a set of remarkable structure relations that are used to integrate the adjoint equations.

Semi-groups and Representations of Lie Groups

With every Lie semi-group, Π, possessing certain regularity properties, there is associated a Lie algebra, A; and with every strongly continuous representation of Π in a Banach space there is associated a representation A(a) of A. Certain theorems regarding this representation are established. The above theorems are valid for a representation of a Lie group also. In this case, it is shown that ...

Semi-Groups and Representations of Lie Groups

The above theorems are valid for a representation of a Lie group also. In this case, it is shown that it is possible to extend the representation to elliptic elements of the universal enveloping algebra. It is also shown that the representatives of the strongly elliptic elements of the universal enveloping algebra are the infinitesimal generators of holomorphic semi-groups. Integral representat...