English
Related papers

Related papers: The Subelliptic Heat Kernel on the CR sphere

200 papers

In this paper we prove that the heat kernel $k$ associated to the operator $A:= (1+|x|^\alpha)\Delta +b|x|^{\alpha-1}\frac{x}{|x|}\cdot\nabla -|x|^\beta$ satisfies $$ k(t,x,y) \leq c_1e^{\lambda_0 t+…

Analysis of PDEs · Mathematics 2017-11-27 S. E. Boutiah , A. Rhandi , C. Tacelli

Aim of this short note is to show that a dimension-free Harnack inequality on an infinitesimally Hilbertian metric measure space where the heat semigroup admits an integral representation in terms of a kernel is suffcient to deduce a sharp…

Probability · Mathematics 2019-07-17 Luca Tamanini

Asymptotic expansions of heat kernels and heat traces of Schr\"odinger operators on non-compact spaces are rarely explored, and even for cases as simple as $\mathbb{C}^n$ with (quasi-homogeneous) polynomials potentials, it's already very…

Differential Geometry · Mathematics 2020-11-12 Xianzhe Dai , Junrong Yan

We consider rough metrics on smooth manifolds and corresponding Laplacians induced by such metrics. We demonstrate that globally continuous heat kernels exist and are H\"older continuous locally in space and time. This is done via local…

Differential Geometry · Mathematics 2018-07-23 Lashi Bandara , Paul Bryan

We give optimal bounds for the radial, space and time derivatives of arbitrary order of the heat kernel of the Laplace--Beltrami operator on Damek--Ricci spaces. In the case of symmetric spaces of rank one, these complete and actually…

Functional Analysis · Mathematics 2022-10-06 Tommaso Bruno , Federico Santagati

We prove a bound on the heat trace of the Neumann Laplacian on a convex domain that captures the first two terms in its small-time expansion, but is valid for all times and depends on the underlying domain only through very simple geometric…

Analysis of PDEs · Mathematics 2026-01-13 Rupert L. Frank , Simon Larson

Let M be a smooth closed (compact without boundary) Riemannian manifold of dimension n and P a q-dimensional smooth submanifold of M. U will denote the tubular neighborhood of P in M. Let E be a smooth vector bundle over M. Here we will…

General Mathematics · Mathematics 2025-12-22 Martin N. Ndumu

An important object of study in harmonic analysis is the heat equation. On a Euclidean space, the fundamental solution of the associated semigroup is known as the heat kernel, which is also the law of Brownian motion. Similar statements…

Representation Theory · Mathematics 2010-05-27 David G Maher

Kernel functions for Laplacian integral operators are constructed on $p$-adic analytic manifolds using charts and transition maps from an atlas with connected nerve complex. In the compact case, an operator of Vladimirov-Taibleson type…

Analysis of PDEs · Mathematics 2025-12-11 Patrick Erik Bradley

We consider second-order elliptic partial differential operators acting on sections of vector bundles over a compact Riemannian manifold without boundary, working without the assumption of Laplace-like principal part $-\N^\mu\N_\mu$. Our…

Mathematical Physics · Physics 2015-06-26 Ivan G. Avramidi , Thomas Branson

The heat kernel associated with an elliptic second-order partial differential operator of Laplace type acting on smooth sections of a vector bundle over a Riemannian manifold, is studied. A general manifestly covariant method for…

High Energy Physics - Theory · Physics 2011-04-20 Ivan G. Avramidi

In this paper we provide the small-time heat kernel asymptotics at the cut locus in three relevant cases: generic low-dimensional Riemannian manifolds, generic 3D contact sub-Riemannian manifolds (close to the starting point) and generic 4D…

Analysis of PDEs · Mathematics 2013-12-12 Davide Barilari , Ugo Boscain , Grégoire Charlot , Robert W. Neel

We study integral kernels of strongly continuous semigroups on Lebesgue spaces over metric measure spaces. Based on semigroup smoothing properties and abstract Morrey-type inequalities, we give sufficient conditions for H\"older or…

Functional Analysis · Mathematics 2024-01-18 Patrizio Bifulco , Delio Mugnolo

Faber-Krahn functions provide lower bounds on the first Dirichlet eigenvalue of the Laplacian and are useful because they imply heat kernel upper bounds. In this paper, we are interested in Faber-Krahn functions and heat kernel estimates…

Probability · Mathematics 2026-01-15 Emily Dautenhahn , Laurent Saloff-Coste

We introduce, for the first time, a Bochner integral formula for the logarithmic Laplacian on any complete Riemannian manifold. This unified framework recovers the classical pointwise expression on Euclidean space and allows us to define…

Analysis of PDEs · Mathematics 2025-06-25 Rui Chen

In the first part of this paper, we study the heat equation and the heat kernel associated with the Heckman-Opdam Laplacian in the compact, Weyl-group invariant setting. In particular, this Laplacian gives rise to a Feller-Markov semigroup…

Classical Analysis and ODEs · Mathematics 2014-05-14 Heiko Remling , Margit Rösler

We consider the problem of allocating a finite number of heat sources in the n-dimensional sphere. When only one such source -assumed to be of infinite temperature- is placed and assuming a constant cooling rate in the sphere, we prove that…

Metric Geometry · Mathematics 2016-09-29 Carlos Beltrán , Nuria Corral , Juan G. Criado del Rey

For $d\ge 2$ and $0<\beta<\alpha<2$, consider a family of non-local operators $\mathcal{L}^{b}=\Delta^{\alpha/2}+\mathcal{S}^{b}$ on $\mathbb{R}^d$, where $$ \mathcal{S}^{b}f(x):=\lim_{\varepsilon\to 0}\mathcal{A}(d,-\beta)\int_{ \{z\in…

Probability · Mathematics 2015-03-19 Zhen-Qing Chen , Ting Yang

In this paper we use the heat equation in a group of Heisenberg type $\mathbb{G}$ to provide a unified treatment of the two very different extension problems for the time independent pseudo-differential operators $\mathscr L^s$ and…

Analysis of PDEs · Mathematics 2021-02-12 Nicola Garofalo , Giulio Tralli

We construct the biharmonic heat kernel for a suitable self-adjoint extension of the bi-Laplacian on a manifold with incomplete edge singularities. We employ a microlocal description of the biharmonic heat kernel to establish mapping…

Spectral Theory · Mathematics 2016-03-25 Boris Vertman