English
Related papers

Related papers: On positivity sets for Helmholtz solutions

200 papers

Consider the one-dimensional stochastic Helmholtz equation where the source is assumed to be driven by the white noise. This paper concerns the stability analysis of the inverse random source problem which is to reconstruct the statistical…

Analysis of PDEs · Mathematics 2016-07-25 Peijun Li , Ganghua Yuan

The focus of this paper is to show the absence of critical points for the solutions to the Helmholtz equation in a bounded domain $\Omega\subset\mathbb{R}^{3}$, given by \[ \left\{ \begin{array}{l} -\rm{div}(a\,\nabla u_{\omega}^{g})-\omega…

Analysis of PDEs · Mathematics 2016-09-07 Giovanni S. Alberti

We establish sharp global regularity results for solutions to nonhomogeneous, nonunifomrly elliptic systems with zero boundary conditions. In particular, we obtain everywhere Lipschitz continuity under borderline Lorentz assumptions on the…

Analysis of PDEs · Mathematics 2022-07-01 Cristiana De Filippis , Mirco Piccinini

This paper addresses an inverse cavity scattering problem associated with the biharmonic wave equation in two dimensions. The objective is to determine the domain or shape of the cavity. The Green's representations are demonstrated for the…

Analysis of PDEs · Mathematics 2023-12-08 Heping Dong , Peijun Li

This article is devoted to review the known results on global well-posedness for the Cauchy problem to the Kirchhoff equation and Kirchhoff systems with small data. Similar results will be obtained for the initial-boundary value problems in…

Analysis of PDEs · Mathematics 2014-12-30 Tokio Matsuyama , Michael Ruzhansky

This paper is devoted to proving the almost global solvability of the Cauchy problem for the Kirchhoff equation in the Gevrey space $\gamma^s_{\eta,L^2}$. Furthermore, similar results are obtained for the initial-boundary value problems in…

Analysis of PDEs · Mathematics 2015-10-22 Tokio Matsuyama , Michael Ruzhansky

The existence theory for solutions to the Boltzmann equation in bounded domains has primarily been developed within uniformly bounded function classes, such as $L^{\infty}_{x,v}$, as in [Duan-Huang-Wang-Yang,2017], [Duan-Wang,2019],…

Analysis of PDEs · Mathematics 2025-08-11 Dingqun Deng , Jong-in Kim , Donghyun Lee

We consider a slightly subcritical elliptic system with Dirichlet boundary conditions and a non-power nonlinearity in a bounded smooth domain. For this problem, standard compact embeddings cannot be used to guarantee the existence of…

Analysis of PDEs · Mathematics 2023-11-20 Mabel Cuesta , Rosa Pardo , Angela Pistoia

In this article we consider the existence of positive singular solutions on bounded domains and also classical solutions on exterior domains. First we consider positive singular solutions of the following problems: \begin{equation}…

Analysis of PDEs · Mathematics 2020-04-15 A. Aghajani , C. Cowan

We prove local well-posedness for the inviscid surface quasigeostrophic (SQG) equation in bounded domains of $\mathbb{R}^2$. When fractional Dirichlet Laplacian dissipation is added, global existence of strong solutions is obtained for…

Analysis of PDEs · Mathematics 2018-08-01 Peter Constantin , Huy Quang Nguyen

In bounded domains, without any geometric conditions, we study the existence and uniqueness of globally Lipschitz and interior strong C^{1,1}, (and classical C^2), solutions of general semilinear oblique boundary value problems for…

Analysis of PDEs · Mathematics 2018-12-05 Feida Jiang , Neil S Trudinger

We consider the Helmholtz transmission problem with one penetrable star-shaped Lipschitz obstacle. Under a natural assumption about the ratio of the wavenumbers, we prove bounds on the solution in terms of the data, with these bounds…

Analysis of PDEs · Mathematics 2022-08-29 Andrea Moiola , Euan A. Spence

We prove an existence theorem for positive solutions to Lichnerowicz-type equations on complete manifolds with boundary and nonlinear Neumann conditions. This kind of nonlinear problems arise quite naturally in the study of solutions for…

Analysis of PDEs · Mathematics 2017-08-16 Guglielmo Albanese , Marco Rigoli

The existence of positive solutions to the system of ordinary differential equations related to the Belousov-Zhabotinsky reaction is established. The key idea is to use successive approximation of solutions, ensuring its positivity. To…

Classical Analysis and ODEs · Mathematics 2019-12-18 Y. Adachi , Novrianti , O. Sawada

We establish Lipschitz stability for both the potential and the initial conditions from a single boundary measurement in the context of a hyperbolic boundary initial value problem. In our setting, the initial conditions are allowed to…

Analysis of PDEs · Mathematics 2025-11-25 Shiqi Ma

This paper deals with existence and multiplicity of positive solutions for a quasilinear problem with Neumann boundary conditions, set in a ball. The problem admits at least one constant non-zero solution and it involves a nonlinearity that…

Analysis of PDEs · Mathematics 2020-02-28 Francesca Colasuonno , Benedetta Noris

We prove existence of multiple positive solutions for a {\sl fractional scalar field equation} in a bounded domain, whenever $p$ tends to the critical Sobolev exponent. By means of the "photography method", we prove that the topology of the…

Analysis of PDEs · Mathematics 2016-10-31 G. M. Figueiredo , G. Siciliano

We consider certain solutions of the Infinity-Laplace Equation in planar convex rings. Their ascending streamlines are unique while the descending ones may bifurcate. We prove that bifurcation occurs in the generic situation and as a…

Analysis of PDEs · Mathematics 2019-02-25 Erik Lindgren , Peter Lindqvist

In this paper we prove global existence of classical solutions to the Vlasov-Poisson and the ionic Vlasov-Poisson models in bounded domains. On the boundary, we consider the specular reflection boundary condition for the Vlasov equation and…

Analysis of PDEs · Mathematics 2023-12-20 Ludovic Cesbron , Mikaela Iacobelli

A characterization of non-hyperbolic pseudoconvex Reinhardt domains in $\mathbb C^2$ for which the answer to the Serre problem is positive is given.

Complex Variables · Mathematics 2012-06-07 Lukasz Kosinski