English
Related papers

Related papers: Gradient Estimate on the Neumann Semigroup and App…

200 papers

The principal aim of this short note is to extend a recent result on Gaussian heat kernel bounds for self-adjoint $L^2(\Om; d^n x)$-realizations, $n\in\bbN$, $n\geq 2$, of divergence form elliptic partial differential expressions $L$ with…

Analysis of PDEs · Mathematics 2013-05-21 Fritz Gesztesy , Marius Mitrea , Roger Nichols , El Maati Ouhabaz

Let $G \subset \mathbb{C}^2$ be a smoothly bounded pseudoconvex domain and assume that the Bergman kernel of $G$ is algebraic of degree $d$. We show that the boundary $\partial G $ is of finite type and the type $r$ satisfies $r\leq 2d$.…

Complex Variables · Mathematics 2021-11-16 Peter Ebenfelt , Ming Xiao , Hang Xu

In this paper, we study the gradient estimate for positive solutions to the following nonlinear heat equation problem $$ u_t-\Delta u=au\log u+Vu, \ \ u>0 $$ on the compact Riemannian manifold $(M,g)$ of dimension $n$ and with non-negative…

Differential Geometry · Mathematics 2010-09-06 Li Ma

We prove a sharp lower bound for the fundamental gap on convex domains in Gaussian spaces, the difference between the first two eigenvalues of the Ornstein-Uhlenbeck operator with Dirichlet boundary conditions. Our main result establishes…

Spectral Theory · Mathematics 2025-10-28 Jin Sun , Kui Wang

This paper investigates gradient estimates on graphs satisfying the $CD\psi(n,-K)$ condition with positive constants $n,K$, and concave $C^{1}$ functions $\psi:(0,+\infty)\rightarrow\mathbb{R}$. Our study focuses on gradient estimates for…

Differential Geometry · Mathematics 2023-12-27 Yi Li , Qianwei Zhang

Refining the sharp upper bounds $\mu_{k,d}^* $ obtained by Kr\"oger (1999) for the $k$-th Neumann eigenvalue of a convex domain $\Omega \subset \mathbb{R}^d$, we prove the following inequalities: for any $k\in \mathbb{N}$ there exists a…

Analysis of PDEs · Mathematics 2026-04-16 Dorin Bucur , Andrea Gentile , Antoine Henrot

We give the upper and the lower estimates of heat kernels for Schr\"odinger operators $H=-\Delta+V$, with nonnegative and locally bounded potentials $V$ in $\mathbb{R}^d$, $d \geq 1$. We observe a factorization: the contribution of the…

Functional Analysis · Mathematics 2023-03-13 Miłosz Baraniewicz , Kamil Kaleta

We investigate the asymptotic behavior of solutions to a semilinear heat equation with homogeneous Neumann boundary conditions. It was recently shown that the nontrivial kernel of the linear part leads to the coexistence of fast solutions…

Analysis of PDEs · Mathematics 2016-07-22 Marina Ghisi , Massimo Gobbino , Alain Haraux

We obtain a new upper bound for Neumann eigenvalues of the Laplacian on a bounded convex domain in Euclidean space. As an application of the upper bound we derive universal inequalities for Neumann eigenvalues of the Laplacian.

Spectral Theory · Mathematics 2023-11-08 Kei Funano

We prove the equivalence of Hardy- and Sobolev-type inequalities, certain uniform bounds on the heat kernel and some spectral regularity properties of the Neumann Laplacian associated with an arbitrary region of finite measure in Euclidean…

Spectral Theory · Mathematics 2007-05-23 V. I. Burenkov , E. B. Davies

In this note we present upper bounds for the variational eigenvalues of the $p$-Laplacian on smooth domains of complete $n$-dimensional Riemannian manifolds and Neumann boundary conditions, and on compact (boundaryless) Riemannian…

Spectral Theory · Mathematics 2021-09-17 Bruno Colbois , Luigi Provenzano

We study the $\bar{\partial}_b$-Neumann problem for domains $\Omega$ contained in a strictly pseudoconvex manifold M^{2n+1} whose boundaries are noncharacteristic and have defining functions depending solely on the real and imaginary parts…

Complex Variables · Mathematics 2008-03-05 Robert K. Hladky

In this paper, we study the scale-invariant quantity \[\mathcal{G}(\Omega)=\frac{\|\partial_n u_1\|_{L^\infty(\partial\Omega)}}{\lambda_1},\]where $u_1$ is the first $L^2$-normalized Dirichlet Laplace eigenfunction of a Euclidean domain…

Numerical Analysis · Mathematics 2026-03-18 Zijian Wang , Jeremy G. Hoskins , Manas Rachh , Alex H. Barnett

We obtain pointwise lower bounds for heat kernels of higher order differential operators with Dirichlet boundary conditions on bounded domains in $\R^N$. The bounds exhibit explicitly the nature of the spatial decay of the heat kernel close…

Spectral Theory · Mathematics 2011-10-18 Narinder S Claire

We introduce a new integral representation formula in the d-bar Neumann Theory on weakly pseudoconvex domains which satisfies certain estimates analogous to the basic L^2 estimate. It is expected that more complete estimates can be obtained…

Complex Variables · Mathematics 2016-01-20 R. Michael Range

We discuss the wellposedness of the Neumann problem on a half-space for the Kohn-Laplacian in the Heisenberg group. We then construct the Neumann function and explicitly represent the solution of the associated inhomogeneous problem.

Analysis of PDEs · Mathematics 2021-05-28 Ashutosh Pandey , Mukund Madhav Mishra , Shivani Dubey

We establish geometric upper and lower estimates for the Carath\'eodory and Kobayashi-Eisenman volume elements on the class of non-degenerate convex domains, as well as on the more general class of non-degenerate $\mathbb{C}$-convex…

Complex Variables · Mathematics 2024-07-17 Debaprasanna Kar

We consider on Riemannian manifolds the nonlinear evolution equation \begin{equation*} \partial _{t}u=\Delta _{p}(u^{1/(p-1)}), \end{equation*}% where $p>1$. This equation is also known as a doubly non-linear parabolic equation or…

Analysis of PDEs · Mathematics 2024-02-19 Philipp Sürig

In this paper, a high-order exponential scheme is developed to solve the 1D unsteady convection-diffusion equation with Neumann boundary conditions. The present method applies fourth-order compact exponential difference scheme in spatial…

Fluid Dynamics · Physics 2018-05-16 Yucheng Fu , Zhenfu Tian , Yang Liu

We derive optimal estimates for the Bergman kernel and the Bergman metric for certain model domains in $\mathbb{C}^2$ near boundary points that are of infinite type. Being unbounded models, these domains obey certain geometric constraints…

Complex Variables · Mathematics 2021-03-25 Gautam Bharali