Essays about: "Sobolev space"

Found 4 essays containing the words Sobolev space.

  1. 1. Multiple Phase Hele-Shaw Flows

    University essay from KTH/Matematik (Avd.)

    Author : Karl Jonsson; [2014]
    Keywords : ;

    Abstract : A one phase Hele-Shaw flow, described by a domain D(t) (t represents time) in the plane is the flow of a liquid injected at a constant rate in the separation between two narrowly separated parallel planes. This thesis deals with the formulation and proof of existence for a multiple phase Hele-Shaw flow in arbitrary dimension R^n exhibiting separation of the phases. READ MORE

  2. 2. Lebesgue points, Hölder continuity and Sobolev functions

    University essay from Matematiska institutionen

    Author : John Karlsson; [2009]
    Keywords : Lebesgue point; Hausdorff dimension; Hausdorff measure; Hölder continuity; Maximal function; Poincaré inequality; Sobolev space; Uniform continuity;

    Abstract : This paper deals with Lebesgue points and studies properties of the set of Lebesgue points for various classes of functions. We consider continuous functions, L1 functions and Sobolev functions. In the case of uniformly continuous functions and Hölder continuous functions we develop a characterization in terms of Lebesgue points. READ MORE

  3. 3. A counterexample concerning nontangential convergence for the solution to the time-dependent Schrödinger equation

    University essay from Matematiska och systemtekniska institutionen

    Author : Karoline Johansson; [2007]
    Keywords : Time-dependent Schrödinger equation; counterexample; nontangential convergence;

    Abstract : Abstract: Considering the Schrödinger equation $\Delta_x u = i\partial{u}/\partial{t}$, we have a solution $u$ on the form $$u(x, t)= (2\pi)^{-n} \int_{\RR} {e^{i x\cdot \xi}e^{it|\xi|^2}\widehat{f}(\xi)}\, d \xi, x \in \RR, t \in \mathbf{R}$$ where $f$ belongs to the Sobolev space. It was shown by Sjögren and Sjölin, that assuming $\gamma : \mathbf{R}_+ \rightarrow \mathbf{R}_+ $ being a strictly increasing function, with $\gamma(0) = 0$ and $u$ and $f$ as above, there exists an $f \in H^{n/2} (\RR)$ such that $u$ is continuous in $\{ (x, t); t>0 \}$ and $$\limsup_{(y,t)\rightarrow (x,0),|y-x|<\gamma (t), t>0} |u(y,t)|= + \infty$$ for all $x \in \RR$. READ MORE

  4. 4. Upper gradients and Sobolev spaces on metric spaces

    University essay from Matematiska institutionen

    Author : David Färm; [2006]
    Keywords : capacity; measure; metric space; Sobolev space; upper gradient;

    Abstract : The Laplace equation and the related p-Laplace equation are closely associated with Sobolev spaces. During the last 15 years people have been exploring the possibility of solving partial differential equations in general metric spaces by generalizing the concept of Sobolev spaces. READ MORE