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In this paper, we are interested in the study of a problem with fractional derivatives having boundary conditions of integral types. The problem represents a Caputo type advection-diffusion equation where the fractional order derivative…

Numerical Analysis · Mathematics 2021-02-23 Saadoune Brahimi , Ahcene Merad , Adem Kilicman

We give an example of a reflected diffferential equation which may have infinitely many solutions if the driving signal is rough enough (e.g. of infinite $p$-variation, for some $p>2$). For this equation, we identify a sharp condition on…

Probability · Mathematics 2020-11-16 Paul Gassiat

This paper generalizes the results of [13] and then provides an interesting example. We construct a family of $W$-like maps $\{W_a\}$ with a turning fixed point having slope $s_1$ on one side and $-s_2$ on the other. Each $W_a$ has an…

Dynamical Systems · Mathematics 2013-10-18 Zhenyang Li

We consider the problem of isotropic effective conductivity $\sigma_e(\sigma_1,\ldots,\sigma_n)$ in two-dimensional three- and four-phase symmetric composites with a partial isotropic conductivity $\sigma_j$ of the $j$-th phase. The upper…

Disordered Systems and Neural Networks · Physics 2025-12-24 Leonid Fel

Let $\Omega \subset \mathbb{R}^d$ be bounded open and connected. Suppose that $W^{1,2}(\Omega) \subset L^r(\Omega)$ for some $r > 2$. Let $A$ be a pure second-order elliptic differential operator with bounded real measurable coefficients on…

Analysis of PDEs · Mathematics 2018-11-26 A. F. M. ter Elst , Hannes Meinlschmidt , Joachim Rehberg

Weakly harmonic maps from a domain $\Omega$ (the upper half-space $\Rd$ or a bounded $C^{1,\alpha}$ domain, $\alpha\in (0,1]$) into a smooth closed manifold are studied. Prescribing small Dirichlet data in either of the classes…

Analysis of PDEs · Mathematics 2021-10-11 Gael Diebou Yomgne , Herbert Koch

We prove the global uniqueness in determination of the conductivity, the permeability and the permittivity of two dimensional Maxwell's equations by partial Dirichlet-to-Neumann map limited to an arbitrary subboundary.

Mathematical Physics · Physics 2014-04-01 O. Yu. Imanuvilov M. Yamamoto

We consider the nonlinear and nonlocal problem $$ A_{1/2}u=|u|^{2^\sharp-2}u\ \text{in \Omega, \quad u=0 \text{on} \partial\Omega $$where $A_{1/2}$ represents the square root of the Laplacian in a bounded domain with zero Dirichlet boundary…

Analysis of PDEs · Mathematics 2010-04-23 Antonio Capella Kort

We consider the problem of the recovery of a Robin coefficient on a part $\gamma \subset \partial \Omega$ of the boundary of a bounded domain $\Omega$ from the principal eigenvalue and the boundary values of the normal derivative of the…

Analysis of PDEs · Mathematics 2020-07-08 Matteo Santacesaria , Toshiaki Yachimura

We prove several universal properties of charge transport in generic CFTs holographic to nonminimal extensions of four-dimensional Einstein-Maxwell theory with exact electromagnetic duality invariance. First, we explicitly verify that the…

High Energy Physics - Theory · Physics 2023-03-24 Ángel J. Murcia , Dmitri Sorokin

Now a final and maybe simplest formulation of the enclosure method applied to inverse obstacle problems governed by partial differential equations in a {\it spacial domain with an outer boundary} over a finite time interval is fixed. The…

Analysis of PDEs · Mathematics 2017-12-07 Masaru Ikehata

We construct anisotropic conductivities with the same Dirichlet-to-Neumann map as a homogeneous isotropic conductivity. These conductivities are singular close to a surface inside the body.

Analysis of PDEs · Mathematics 2007-05-23 Allan Greenleaf , Matti Lassas , Gunther Uhlmann

We study some inverse problems for time-fractional Schr\"odinger equations involving the Caputo derivative of fractional order $\alpha \in (0,1)$. We prove refined uniqueness results from sets of positive Lebesgue measure for various…

Analysis of PDEs · Mathematics 2025-11-13 S. E. Chorfi , F. Et-tahri , L. Maniar , M. Yamamoto

This study addresses the inverse source problem for the fractional diffusion-wave equation, characterized by a source comprising spatial and temporal components. The investigation is primarily concerned with practical scenarios where data…

Numerical Analysis · Mathematics 2025-04-22 Lingyun Qiu , Jiwoon Sim

Let $\Omega \subset \mathbb{R}^N$, $N \geq 2$, be a smooth bounded domain. For $s \in (1/2,1)$, we consider a problem of the form \[ \left\{\begin{aligned} (-\Delta)^s u & = \mu(x)\, \mathbb{D}_s^{2}(u) + \lambda f(x)\,, & \quad \mbox{in}…

Analysis of PDEs · Mathematics 2018-12-04 Boumediene Abdellaoui , Antonio J. Fernández

This paper shows global uniqueness in an inverse problem for a fractional magnetic Schr\"odinger equation (FMSE): an unknown electromagnetic field in a bounded domain is uniquely determined up to a natural gauge by infinitely many…

Analysis of PDEs · Mathematics 2019-10-14 Giovanni Covi

Consider a quantum graph consisting of a ring with two attached edges, and assume Kirchhoff-Neumann conditions hold at the internal vertices. Associated to this graph is a Schr\"{o}dinger type operator $L=-\Delta +q(x)$ with Dirichlet…

Analysis of PDEs · Mathematics 2025-08-15 Sergei Avdonin , Julian Edward

We consider the inverse conductivity problem of identifying embedded objects in unbounded domains. The main tool is a set of special solutions to the Schroedinger equation, the complex spherical waves, which are constructed by a Carleman…

Analysis of PDEs · Mathematics 2009-11-11 Mikko Salo , Jenn-Nan Wang

We study the Dirichlet problem for least gradient functions for domains in metric spaces equipped with a doubling measure and supporting a (1,1)-Poincar\'e inequality when the boundary of the domain satisfies a positive mean curvature…

Analysis of PDEs · Mathematics 2022-10-18 Josh Kline

Let $\Omega,\Omega'\subset\mathbb{R}^3$ be Lipschitz domains, let $f_m:\Omega\to\Omega'$ be a sequence of homeomorphisms with prescribed Dirichlet boundary condition and $\sup_m \int_{\Omega}(|Df_m|^2+1/J^2_{f_m})<\infty$. Let $f$ be a weak…

Functional Analysis · Mathematics 2025-10-14 Anna Doležalová , Stanislav Hencl , Jan Malý