English
Related papers

Related papers: The Kato square root problem for mixed boundary va…

200 papers

We solve the Kato square root problem for general elliptic operators and systems with measurable and complex coefficients on any domain of the Euclidean space. The operators are subject to Dirichlet boundary conditions. We also allow…

Analysis of PDEs · Mathematics 2020-03-23 Julan Bailey , El Maati Ouhabaz

We obtain the Kato square root estimate for second order elliptic operators in divergence form with mixed boundary conditions on an open and possibly unbounded set in $\mathbb{R}^d$ under two simple geometric conditions: The Dirichlet…

Functional Analysis · Mathematics 2020-12-04 Sebastian Bechtel , Moritz Egert , Robert Haller-Dintelmann

This article focuses on Lp-estimates for the square root of elliptic systems of second order in divergence form on a bounded domain. We treat complex bounded measurable coefficients and allow for mixed Dirichlet/Neumann boundary conditions…

Classical Analysis and ODEs · Mathematics 2021-03-29 Moritz Egert

We consider the negative Laplacian subject to mixed boundary conditions on a bounded domain. We prove under very general geometric assumptions that slightly above the critical exponent $\frac{1}{2}$ its fractional power domains still…

Functional Analysis · Mathematics 2021-08-10 Moritz Egert , Robert Haller-Dintelmann , Patrick Tolksdorf

We solve the Kato square root problem for divergence form operators on complete Riemannian manifolds that are embedded in Euclidean space with a bounded second fundamental form. We do this by proving local quadratic estimates for…

Analysis of PDEs · Mathematics 2014-02-26 Andrew J. Morris

We obtain the Kato square root property for coupled second-order elliptic systems in divergence form subject to mixed boundary conditions on an open and possibly unbounded set in $\mathbb{R}^n$ under two simple geometric conditions: The…

Functional Analysis · Mathematics 2025-09-03 Sebastian Bechtel , Cody Hutcheson , Tim Schmatzler , Tolgahan Tasci , Mattes Wittig

We provide a direct proof of a quadratic estimate that plays a central role in the determination of domains of square roots of elliptic operators and, as shown more recently, in some boundary value problems with $L^2$ boundary data. We…

Classical Analysis and ODEs · Mathematics 2009-05-18 Pascal Auscher , Andreas Axelsson , Alan McIntosh

On a domain $\Omega \subseteq \mathbb{R}^d$ we consider second order elliptic systems in divergence form with bounded complex coefficients, realized via a sesquilinear form with domain $V \subseteq H^1(\Omega)$. Under very mild assumptions…

Functional Analysis · Mathematics 2021-08-10 Moritz Egert , Robert Haller-Dintelmann , Patrick Tolksdorf

We consider the Kato square root problem for non-divergence second order elliptic operators $L =- a_{ij} D_iD_j$, and, especially, the normalized adjoints of such operators. In particular, our results are applicable to the case of real…

Analysis of PDEs · Mathematics 2023-10-06 Luis Escauriaza , Pablo Hidalgo-Palencia , Steve Hofmann

We consider the Kato problem and extensions for degenerate elliptic operators of arbitrary order $2m$ ($m\geq 1$), whose coefficients are measurable, complex-valued and satisfy the G$\mathring{a}$rding inequality with respect to a…

Analysis of PDEs · Mathematics 2025-11-07 Guoming Zhang

We solve the Kato square root problem for bounded measurable perturbations of subelliptic operators on connected Lie groups. The subelliptic operators are divergence form operators with complex bounded coefficients, which may have lower…

Analysis of PDEs · Mathematics 2016-03-09 Lashi Bandara , A. F. M. ter Elst , Alan McIntosh

Weighted quadratic estimates are proved for certain bisectorial firstorder differential operators with bounded measurable coefficients which are (not necessarily pointwise) accretive, on complete manifolds with positive injectivity radius.…

Analysis of PDEs · Mathematics 2024-05-29 Pascal Auscher , Andrew J. Morris , Andreas Rosén

We solve the Kato square root problem for parabolic operators of arbitrary order $2m$ whose coefficients are allowed to depend on both space and time in a merely measurable way and possess boundedness and ellipticity controlled by a…

Analysis of PDEs · Mathematics 2025-11-10 Guoming Zhang

We prove the Kato conjecture for degenerate elliptic operators in R^n. More precisely, we consider the divergence form operator L_w = -1/w div (wA) grad, where w is a Muckenhoupt A_2 weight and A is a complex valued n x n matrix which is…

Analysis of PDEs · Mathematics 2009-07-20 D. Cruz-Uribe , C. Rios

We study the Dirichlet problem in Lipschitz domains and with boundary data in Besov spaces, for divergence form strongly elliptic systems of arbitrary order, with bounded, complex-valued coefficients. Our main result gives a sharp condition…

Analysis of PDEs · Mathematics 2007-05-23 Vladimir Maz'ya , Marius Mitrea , Tatyana Shaposhnikova

Let $L$ be an elliptic differential operator with bounded measurable coefficients, acting in Bochner spaces $L^{p}(R^{n};X)$ of $X$-valued functions on $R^n$. We characterize Kato's square root estimates $\|\sqrt{L}u\|_{p} \eqsim \|\nabla…

Functional Analysis · Mathematics 2007-05-23 Tuomas Hytonen , Alan McIntosh , Pierre Portal

We prove the first positive results concerning boundary value problems in the upper half-space of second order parabolic systems only assuming measurability and some transversal regularity in the coefficients of the elliptic part. To do so,…

Classical Analysis and ODEs · Mathematics 2023-07-03 Pascal Auscher , Moritz Egert , Kaj Nyström

We prove the Kato square root estimate for second-order divergence form elliptic operators $-div(A\nabla)$ on a bounded, locally uniform domain $D \subseteq \mathbb{R}^n$, for accretive coefficients $A \in L^\infty(D; \mathbb{C}^n)$, under…

Analysis of PDEs · Mathematics 2026-01-09 Sebastian Bechtel , Andreas Rosén

The Kato square root problem for divergence form elliptic operators with potential $V : \mathbb{R}^{n} \rightarrow \mathbb{C}$ is the equivalence statement $\left\Vert (L + V)^{\frac{1}{2}} u\right\Vert_{2} \simeq \left\Vert \nabla u…

Functional Analysis · Mathematics 2020-06-24 Julian Bailey

We give a simplified and direct proof of the Kato square root estimate for parabolic operators with elliptic part in divergence form and coefficients possibly depending on space and time in a merely measurable way. The argument relies on…

Analysis of PDEs · Mathematics 2022-09-23 Alireza Ataei , Moritz Egert , Kaj Nyström
‹ Prev 1 2 3 10 Next ›