Results 41 to 50 of about 508 (55)

Ornstein-Uhlenbeck semi-groups on stratified groups [PDF]

arXiv, 2009
We consider, in the setting of stratified groups G, two analogues of the Ornstein-Uhlenbeck semi-group, namely Markovian diffusion semi-groups acting on $L^q(pd g)$, whose invariant density $p$ is a heat kernel at time 1 on G.
arxiv  

Geometric inequalities in Carnot groups [PDF]

arXiv, 2012
Let $\GG$ be a sub-Riemannian $k$-step Carnot group of homogeneous dimension $Q$. In this paper, we shall prove several geometric inequalities concerning smooth hypersurfaces (i.e. codimension one submanifolds) immersed in $\GG$, endowed with the $\HH$-perimeter measure.
arxiv  

Polynomial and horizontally polynomial functions on Lie groups. [PDF]

Ann Mat Pura Appl, 2022
Antonelli G, Le Donne E.
europepmc   +1 more source

An integral formula on the Heisenberg group [PDF]

arXiv, 2012
Let Hn denote the (2n + 1)-dimensional (sub-Riemannian) Heisenberg group. In this note, we shall prove an integral identity (see Theorem 1.2) which generalizes a formula obtained in the Seventies by Reilly. Some first applications will be given in Section 4.
arxiv  

Some existence results for the Webster scalar curvature problem in presence of symmetry [PDF]

arXiv, 2002
We prove some existence results for the Webster scalar curvature problem on the Heisenberg group and on the unit sphere of ${\mathbb C}^{n+1}$, under the assumption of some natural symmetries of the prescribed curvatures. We use variational and perturbation techniques.
arxiv  

A Note on the Ruin Problem with Risky Investments [PDF]

arXiv, 2005
We reprove a result concerning certain ruin in the classical problem of the probability of ruin with risky investments and several of it's generalisations. We also provide the combined transition density of the risk and investment processes in the diffusion case.
arxiv  

A Restriction Theorem for M\'etivier Groups

, 2013
In the spirit of an earlier result of M\"uller on the Heisenberg group we prove a restriction theorem on a certain class of two step nilpotent Lie groups.
Casarino, Valentina, Ciatti, Paolo
core  

Sampling theorems on locally compact groups from oscillation estimates [PDF]

arXiv, 2005
We present a general approach to derive sampling theorems on locally compact groups from oscillation estimates. We focus on the ${\rm L}^2$-stability of the sampling operator by using notions from frame theory. This approach yields particularly simple and transparent reconstruction procedures.
arxiv  

On Value Distributions for Quasimeromorphic Mappings on $\mathbb H$-type Carnot Groups [PDF]

arXiv, 2005
In the present paper we define quasimeromorphic mappings on homogeneous groups and study their properties. We prove an analogue of results of L. Ahlfors, R. Nevanlinna and S. Rickman, concerning the value distribution for quasimeromorphic mappings on $\mathbb H$-type Carnot groups for parabolic and hyperbolic type domains.
arxiv  

Strongly singular Radon transforms on the Heisenberg group and folding singularities [PDF]

arXiv, 2006
We prove sharp $L^2$ regularity results for classes of strongly singular Radon transfoms on the Heisenberg group by means of oscillatory integrals. We show that the problem in question can be effectively treated by establishing uniform estimates for certain oscillatory integrals whose canonical relations project with two-sided fold singularities; this ...
arxiv