1,720,994 research outputs found

    Embedding results

    No full text

    Bounds in spaces of Morrey under Cordes type conditions

    No full text
    In the study of boundary value problems for linear elliptic equations in nondivergence form with discontinuous coefficients we consider the class of discontinuity of Cordes type. In particular we state some local and non local a priori bounds for solutions of Dirichlet problem in unbounded domains. The coefficients of lower terms in the differential operator belong to Morrey spaces and the principal coefficients are 'near' to functions satisfying a condition of Cordes type. Our results are based on embedding theorems which allow us to require a summability lower than n for the coefficients of the operator L. We introduce a modulus of continuity of the functions in Morrey spaces to obtain the dependence of the constants in the estimates. We state also a result about the multiplication operator from W^1(\Omega) in L^2(\Omega)

    A class of weighted Hardy type inequalities in R^N

    No full text
    In the paper we prove the weighted Hardy type inequality \begin{equation} \int_{{\mathbb R}^N}V\varphi^2 \mu(x)dx\le \int_{\R^N}|\nabla \varphi|^2\mu(x)dx +K\int_{\R^N}\varphi^2\mu(x)dx, \end{equation} for functions φ\varphi in a weighted Sobolev space Hμ1H^1_\mu, for a wider class of potentials VV than inverse square potentials and for weight functions μ\mu of a quite general type. The case μ=1\mu=1 is included. To get the result we introduce a generalized vector field method. The estimates apply to evolution problems with Kolmogorov operators \begin{equation*} Lu=\Delta u+\frac{\nabla \mu}{\mu}\cdot\nabla u \end{equation*} perturbed by singular potentials

    Existence and uniqueness results in Morrey type spaces

    No full text
    We consider boundary value problems for linear elliptic equations in nondivergence form with discontinuous coefficients when the class of discontinuity is of Chicco type. The main result we state is an existence ad uniqueness theorem for solutions of Dirichlet problem in unbounded domains. To this aim we introduce a regularization of the principal coefficients of the differential operator. Basic tools to prove the result are some a priori bounds stated in a previous paper

    An embedding result

    No full text
    In unbounded subset in R^n we study the multiplication operator as an operator defined in Sobolev spaces and which takes values in L^p. The functions g belong to wider spaces of L^p connected with the Morrey type spaces. The main result is an embedding theorem from which we an deduce a Fefferman type inequality

    On some results in weighted spaces under Chicco type conditions

    No full text
    In the present paper we consider weighted spaces where the weight is related to the distance function from a fixed subset S of \partial\Omega. In unbounded domains we study Dirichlet problem for linear elliptic equations in nondivergence form with discontinuous coefficients when the class of discontinuity is of Chicco type. In particular we state some local and non local a priori bounds and study the dependence of the constants in the estimates. The coefficients of lower terms in the differential operator belong to weighted spaces and the principal coefficients are 'near' to functions satisfying a condition of Chicco type. The conditions we impose on the coefficients allow us to apply embedding results to get local estimates
    corecore