arXiv subjects
Publications and source records attributed to Katharine A. Ott.
We consider a class of Brascamp-Lieb forms and give conditions which guarantee the boundedness of these form on $L^p$-spaces with weights that are a power of the distance to the origin. These conditions are close to necessary and sufficient.
We establish a set of necessary conditions and a set of sufficient conditions for boundedness of a family of Brascamp-Lieb forms in Lorentz spaces and $L^p$-spaces with power weights. The conditions are close to optimal.
We consider the mixed boundary value problem or Zaremba's problem for the Laplacian in a bounded Lipschitz domain in R^n. We specify Dirichlet data on part of the boundary and Neumann data on the remainder of the boundary. We assume that the boundary between the sets where we specify Dirichlet and Neumann data is a Lipschitz surface. We require that the Neumann data is in L^p and the Dirichlet data is in the Sobolev space of functions having one derivative in L^p for some p near 1. Under these conditions, there is a unique solution to the mixed problem with the non-tangential maximal function of the gradient of the solution in L^p of the boundary. We also obtain results with data from Hardy spaces when p=1.
We consider the mixed problem for $L$ the Lamé system of elasticity in a bounded Lipschitz domain $ Ω\subset\reals ^2$. We suppose that the boundary is written as the union of two disjoint sets, $\partialΩ=D\cup N$. We take traction data from the space $L^p(N)$ and Dirichlet data from a Sobolev space $ W^{1,p}(D)$ and look for a solution $u$ of $Lu =0$ with the given boundary conditions. We give a scale invariant condition on $D$ and find an exponent $ p_0 >1$ so that for $1<p<p_0$, we have a unique solution of this boundary value problem with the non-tangential maximal function of the gradient of the solution in $L^ p(\partialΩ)$. We also establish the existence of a unique solution when the data is taken from Hardy spaces and Hardy-Sobolev spaces with $ p$ in $(p_1,1]$ for some $p_1 <1$.
This paper continues the study of the mixed problem for the Laplacian. We consider a bounded Lipschitz domain $Ω\subset \reals^n$, $n\geq2$, with boundary that is decomposed as $\partialΩ=D\cup N$, $D$ and $N$ disjoint. We let $Λ$ denote the boundary of $D$ (relative to $\partialΩ$) and impose conditions on the dimension and shape of $Λ$ and the sets $N$ and $D$. Under these geometric criteria, we show that there exists $p_0>1$ depending on the domain $Ω$ such that for $p$ in the interval $(1,p_0)$, the mixed problem with Neumann data in the space $L^p(N)$ and Dirichlet data in the Sobolev space $W^ {1,p}(D) $ has a unique solution with the non-tangential maximal function of the gradient of the solution in $L^p(\partialΩ)$. We also obtain results for $p=1$ when the Dirichlet and Neumann data comes from Hardy spaces, and a result when the boundary data comes from weighted Sobolev spaces.