Search results for "function spaces"

showing 3 items of 3 documents

Well-posedness and singularity formation for the Camassa-Holm equation

2006

We prove the well-posedness of Camassa--Holm equation in analytic function spaces both locally and globally in time, and we investigate numerically the phenomenon of singularity formation for particular initial data.

Camassa-Holm equation complex singularities analytic function spacesSettore MAT/07 - Fisica Matematica
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MR2524292 (2010f:26007): Kolyada, V. I.; Lind, M. On functions of bounded p-variation. J. Math. Anal. Appl. 356 (2009), no. 2, 582–604. (Reviewer: Lu…

2009

For p∈(1,+∞), let f∈Lp be a 1-periodic function on the real line, with the norm of f given by ∥f∥p=(∫10|f(x)|pdx)1/p. The Lp-modulus of continuity of f is defined by ω(f,δ)p=sup0≤h≤δ(∫10|f(x+h)−f(x)|pdx)1/p, 0≤δ≤1. A partition of period 1 (or simply a partition) is a set Π={x0,x1,…,xn} of points such that x0<x1<…<xn=x0+1. For a given partition Π={x0,x1,…,xn} let vp(f;Π)=(∑k=0n−1|f(xk+1)−f(xk)|p)1/p. The modulus of p-continuity of f is defined by ω1−1/p(f,δ)=sup∥Π∥≤δvp(f;Π), where the supremum is taken over all partitions Π such that ∥Π∥=maxk(xk+1−xk)≤δ. In this paper, improving a previous estimate given by A. P. Terehin [Mat. Zametki 2 (1967), 289--300; MR0223512 (36 #6560)], it is shown th…

Modulus of continuityFunctions of bounded p-variationFunction spacesOptimal constant factor
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Differential of metric valued Sobolev maps

2020

We introduce a notion of differential of a Sobolev map between metric spaces. The differential is given in the framework of tangent and cotangent modules of metric measure spaces, developed by the first author. We prove that our notion is consistent with Kirchheim's metric differential when the source is a Euclidean space, and with the abstract differential provided by the first author when the target is $\mathbb{R}$.

metric measure spacesPure mathematicsFunction spaces; Metric measure spaces; Sobolev spaces01 natural sciencesMetric measure spacesfunction spacesSettore MAT/05 - Analisi Matematica0103 physical sciencesFOS: MathematicsTrigonometric functions0101 mathematicsMathematicsEuclidean space010102 general mathematicsTangentmetriset avaruudetFunctional Analysis (math.FA)Mathematics - Functional AnalysisSobolev spaceMetric spaceSobolev spacesFunction spaces010307 mathematical physicsfunktionaalianalyysiMetric differentialAnalysisJournal of Functional Analysis
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