English
Related papers

Related papers: Heat properties for groups

200 papers

Let $(\mathbb{G},\circ)$ be a stratified Lie group. We estimate the Hausdorff dimension (with respect to the Carnot-Carath\'eodory metric) of the singular sets in $\mathbb{G}$, where a positive solution of the Heat equation corresponding to…

Classical Analysis and ODEs · Mathematics 2025-09-04 Utsav Dewan

We show that Property $\mathrm{(TTT)}$ is an obstruction to weak amenability with Cowling--Haagerup constant $1$. More precisely, if $G$ is a countable group and $H$ is an infinite subgroup of $G$ such that the pair $(G,H)$ has relative…

Group Theory · Mathematics 2024-10-10 Ignacio Vergara

We give a partial solution to a long-standing open problem in the theory of quantum groups, namely we prove that all finite-dimensional representations of a wide class of locally compact quantum groups factor through matrix quantum groups…

Operator Algebras · Mathematics 2019-01-28 Biswarup Das , Matthew Daws , Pekka Salmi

We show that for any non--elementary hyperbolic group $H$ and any finitely presented group $Q$, there exists a short exact sequence $1\to N\to G\to Q\to 1$, where $G$ is a hyperbolic group and $N$ is a quotient group of $H$. As an…

Group Theory · Mathematics 2011-11-09 Igor Belegradek , Denis Osin

Kazhdan's notion of property T has recently been imported to the C$^*$-world by Bekka. Our objective is to extend a well known fact to this realm; we show that a nuclear C$^*$-algebra with property T is finite dimensional (for all intents…

Operator Algebras · Mathematics 2007-05-23 Nathanial P. Brown

This paper investigates the application of the classical Chernoff's theorem to construct explicit solutions for the heat and Schr\"odinger equations on the Heisenberg group $\mathbb{H}^d$. Using semigroup approximation techniques, we obtain…

Analysis of PDEs · Mathematics 2025-03-25 Nicolò Drago , Sonia Mazzucchi , Andrea Pinamonti

We extend the Delorme-Guichardet characterization of Kazhdan property $T$ groups to $r$-discrete measured groupoids. We give several applications, in particular to stability results of Kazhdan property $T$ and to the study of cocycles…

Dynamical Systems · Mathematics 2007-05-23 Claire Anantharaman-Delaroche

In this paper we explore the weak solutions of the Cauchy problem and an inverse source problem for the heat equation in the quantum calculus, formulated in abstract Hilbert spaces. For this we use the Fourier series expansions. Moreover,…

Analysis of PDEs · Mathematics 2022-12-16 Michael Ruzhansky , Serikbol Shaimardan

We introduce some new classes of time dependent functions whose defining properties take into account of oscillations around singularities. We study properties of solutions to the heat equation with coefficients in these classes which are…

Analysis of PDEs · Mathematics 2007-05-23 Qi S. Zhang

It is shown that a locally compact second countable group $G$ has the Haagerup property if and only if there exists a sharply weak mixing 0-type measure preserving free $G$-action $T=(T_g)_{g\in G}$ on an infinite $\sigma$-finite standard…

Dynamical Systems · Mathematics 2021-10-28 Alexandre I. Danilenko

Let $G$ be a subgroup of a discrete (countable) group $\Gamma$. We introduce a notion of relative inner amenability of $G$ in $\Gamma$, we prove some equivalent conditions and provide examples as well as counter-examples. We also discuss…

Group Theory · Mathematics 2013-12-03 Paul Jolissaint

D. A. Kahzdan first put forth property (T) in relation to the study of discrete subgroups of Lie groups of finite co-volume. Through a combinatorial approach, we define an analogue of property (T) for regular graphs. We then prove the basic…

Combinatorics · Mathematics 2007-05-23 Clara Brasseur , Ryan E. Grady , Stratos Prassidis

We consider weak solutions of the fractional heat equation posed in the whole $n$-dimensional space, and establish their asymptotic convergence to the fundamental solution as $t\to\infty$ under the assumption that the initial datum is an…

Analysis of PDEs · Mathematics 2017-10-18 Juan Luis Vázquez

We present a new proof of the caloric smoothing related to the fractional Gauss-Weierstrass semi-group in Triebel-Lizorkin spaces. This property will be used to prove existence and uniqueness of mild and strong solutions of the Cauchy…

Analysis of PDEs · Mathematics 2024-02-12 Franka Baaske , Hans-Jürgen Schmeißer , Hans Triebel

For each countable group $Q$ we produce a short exact sequence $1\to N \to G \to Q\to 1$ where $G$ is f.g. and has a graphical $\frac16$ presentation and $N$ is f.g. and satisfies property $T$. As a consequence we produce a group $N$ with…

Group Theory · Mathematics 2007-05-23 Yann Ollivier , Daniel T. Wise

The overarching goal of this paper is to link the notion of sets of finite perimeter (a concept associated with $N^{1,1}$-spaces) and the theory of heat semigroups (a concept related to $N^{1,2}$-spaces) in the setting of metric measure…

Analysis of PDEs · Mathematics 2016-06-13 Niko Marola , Michele Miranda , Nageswari Shanmugalingam

In this article we deal with the backward uniqueness property of the heat equation in conical domains in two spatial dimensions via Carleman inequality techniques. Using a microlocal interpretation of the pseudoconvexity condition, we…

Analysis of PDEs · Mathematics 2015-09-29 Angkana Rüland

In this paper, we consider a semi-classical version of the nonhomogeneous heat equation with singular time-dependent coefficients on the lattice $\hbar \mathbb{Z}^n$. We establish the well-posedeness of such Cauchy equations in the…

Analysis of PDEs · Mathematics 2025-04-30 Marianna Chatzakou , Aparajita Dasgupta , Michael Ruzhansky , Abhilash Tushir

In this paper we obtain necessary conditions and sufficient conditions on the initial data for the solvability of fractional semilinear heat equations with power nonlinearities in the Heisenberg group $\mathbb{H}^N$. Using these conditions,…

Analysis of PDEs · Mathematics 2024-09-02 The Anh Bui , Kotaro Hisa

In this paper, we regularize the nonlinear inverse time heat problem in the unbounded region by Fourier method. Some new convergence rates are obtained. Meanwhile, some quite sharp error estimates between the approximate solution and exact…

Analysis of PDEs · Mathematics 2009-11-16 Alain Pham Ngoc Dinh , Dang Duc Trong , Pham Hoang Quan , Nguyen Huy Tuan