Results 51 to 60 of about 553 (167)
A comparison principle for nonlinear heat Rockland operators on graded groups
Abstract In this note we show a comparison principle for nonlinear heat Rockland operators on graded groups. We give a simple proof for it using purely algebraic relations. As an application of the established comparison principle we prove the global in t‐boundedness of solutions for a class of nonlinear equations for the heat p‐sub‐Laplacian on ...
Michael Ruzhansky, Durvudkhan Suragan
wiley +1 more source
Null-controllability of hypoelliptic quadratic differential equations [PDF]
46 pagesInternational audienceWe study the null-controllability of parabolic equations associated to a general class of hypoelliptic quadratic differential operators.
Karel Pravda-Starov +3 more
core +1 more source
Dunkl convolution and elliptic regularity for Dunkl operators
Abstract We discuss in which cases the Dunkl convolution u∗kv$u*_kv$ of distributions u,v$u,v$, possibly both with non‐compact support, can be defined and study its analytic properties. We prove results on the (singular‐)support of Dunkl convolutions.
Dominik Brennecken
wiley +1 more source
LOWER ORDER PERTURBATION AND GLOBAL ANALYTIC VECTORS FOR A CLASS OF GLOBALLY ANALYTIC HYPOELLIPTIC OPERATORS [PDF]
In this work we return to the class of globally analytic hypoelliptic Hormander's operators defined on the N-dimensional torus introduced by Cordaro and Himonas and prove that if P is any operator in this class, then a perturbation of P by an analytic ...
Jahnke, MR +3 more
core +1 more source
On a rigidity result for Kolmogorov-type operators
Let D be a bounded open subset of ℝN and let z0 be a point of D. Assume that the Newtonian potential of D is proportional outside D to the potential of a mass concentrated at z0. Then D is a Euclidean ball centred at z0. This theorem, proved by Aharonov,
Alessia E. Kogoj
doaj +1 more source
The Uncertainty Principle and Hypoelliptic Operators
Let P be a differential operator of second order with coefficients in \(C^{\infty}(R^ n)\), that is, \[ (1)\quad P=\sum_{j,k}a_{jk}(x)D_ jD_ k+\sum_{j}ib_ j(x)D_ j+c(x),\quad D_ j=-i\partial_{x_ j}. \] We assume that \[ (2)\quad a_{jk}\quad and\quad b_ j\quad are\quad real\quad valued,\quad \sum a_{jk}(x)\xi_ j\xi_ k\geq 0\quad for\quad any\quad (x,\xi)
openaire +3 more sources
Abstract The aim of this paper is to prove the existence of Hadamard states for the Maxwell equations on any globally hyperbolic spacetime. This will be achieved by introducing a new gauge fixing condition, the Cauchy radiation gauge, that will allow to suppress all the unphysical degrees of freedom. The key ingredient for achieving this gauge is a new
Simone Murro, Gabriel Schmid
wiley +1 more source
Let $\mathcal{L}$ be the hypoelliptic Ornstein-Uhlenbeck operator associated with the pair of matrices (A,B). In 2004, Priola and Zabczyk proved the following Liouville-type theorem: every bounded entire solution of $\mathcal{L}u=0$ is constant if and ...
Alessia E. Kogoj +2 more
doaj +1 more source
On curvature bounds in Lorentzian length spaces
Abstract We introduce several new notions of (sectional) curvature bounds for Lorentzian pre‐length spaces: On the one hand, we provide convexity/concavity conditions for the (modified) time separation function, and, on the other hand, we study four‐point conditions, which are suitable also for the non‐intrinsic setting. Via these concepts, we are able
Tobias Beran +2 more
wiley +1 more source
The analysis of the hypoelliptic Laplacian [PDF]
This chapter constructs a functional analytic machinery that is adapted to the analysis of the hypoelliptic Laplacian ℒA,bX. The analysis of the hypoelliptic Laplacian essentially consists in the construction of Sobolev spaces on which the operators ℒA ...
Jean-Michel Bismut
core +1 more source

