Search results for "Radon measure"

showing 10 items of 13 documents

A space on which diameter-type packing measure is not Borel regular

1999

We construct a separable metric space on which 1-dimensional diameter-type packing measure is not Borel regular.

CombinatoricsBorel equivalence relationRiesz–Markov–Kakutani representation theoremApplied MathematicsGeneral MathematicsRadon measureStandard probability spaceBaire measureBorel setBorel measureMeasure (mathematics)MathematicsProceedings of the American Mathematical Society
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Regularity of renormalized solutions to nonlinear elliptic equations away from the support of measure data

2018

We prove boundedness and continuity for solutions to the Dirichlet problem for the equation $$ - {\rm{div}}(a(x,\nabla u)) = h(x,u) + \mu ,\;\;\;\;\;{\rm{in}}\;{\rm{\Omega }} \subset \mathbb{R}^{N},$$ where the left-hand side is a Leray-Lions operator from $$- {W}^{1,p}_0(\Omega)$$ into W−1,p′(Ω) with 1 < p < N, h(x,s) is a Caratheodory function which grows like ∣s∣p−1 and μ is a finite Radon measure. We prove that renormalized solutions, though not globally bounded, are Holder-continuous far from the support of μ.

Dirichlet problemElliptic partial differential equations; boundary-value problems; regularity; Hölder-continuityregularityOperator (physics)boundary-value problemsElliptic partial differential equationsHölder-continuityMeasure (mathematics)OmegaCombinatoricsBounded functionRadon measurep-LaplacianNabla symbolMathematics
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Nonlinear Potential Theory and PDEs

1994

We consider equations like — div(∣∇u∣ p-2∇u) = µ, where µ is a nonnegative Radon measure and 1 < p < ∞. Results that relate the solution u and the measure µ are reviewed. A link between potential estimates and the boundary regularity of the Dirichlet problem is established.

Dirichlet problemNonlinear systemMathematical analysisRadon measureMathematics::Analysis of PDEsBoundary (topology)Link (knot theory)Measure (mathematics)Potential theoryMathematics
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Some regularity results on the ‘relativistic’ heat equation

2008

AbstractWe prove some partial regularity results for the entropy solution u of the so-called relativistic heat equation. In particular, under some assumptions on the initial condition u0, we prove that ut(t) is a Radon measure in RN. Moreover, if u0 is log-concave inside its support Ω, Ω being a convex set, then we show the solution u(t) is also log-concave in its support Ω(t). This implies its smoothness in Ω(t). In that case we can give a simpler characterization of the notion of entropy solution.

Flux limited diffusion equationsEntropy solutionsApplied MathematicsHeat equationMathematical analysisRadon measureConvex setInitial value problemHeat equationAnalysisMathematicsJournal of Differential Equations
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Equivalence Relations on Stonian Spaces

1996

Abstract Quotient spaces of locally compact Stonian spaces which generalize in some sense the concept of Stone representation space of a Boolean algebra are investigated emphasizing the measure theoretical point of view, and a representation theorem for finitely additive measures is proved.

Mathematics(all)Representation theoremquotient spaceRiesz–Markov–Kakutani representation theoremGeneral Mathematicsba spacerepresentation of a space of measuresQuotient space (linear algebra)Stone representation spaceAlgebranormal Radon measureStonian spaceEquivalence relationLocally compact spaceStone's representation theorem for Boolean algebrasQuotientfinitely additive measureMathematicsAdvances in Mathematics
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A short proof of the infinitesimal Hilbertianity of the weighted Euclidean space

2020

We provide a quick proof of the following known result: the Sobolev space associated with the Euclidean space, endowed with the Euclidean distance and an arbitrary Radon measure, is Hilbert. Our new approach relies upon the properties of the Alberti-Marchese decomposability bundle. As a consequence of our arguments, we also prove that if the Sobolev norm is closable on compactly-supported smooth functions, then the reference measure is absolutely continuous with respect to the Lebesgue measure.

Mathematics::Functional AnalysisPure mathematicsLebesgue measureEuclidean spaceGeneral Mathematics010102 general mathematicsAbsolute continuity01 natural sciencesMeasure (mathematics)Functional Analysis (math.FA)Mathematics - Functional AnalysisdifferentiaaligeometriaEuclidean distanceSobolev spaceNorm (mathematics)0103 physical sciencesRadon measureFOS: Mathematics010307 mathematical physics0101 mathematicsfunktionaalianalyysi53C23 46E35 26B05MathematicsComptes Rendus. Mathématique
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Porous measures on $\mathbb {R}^{n}$: Local structure and dimensional properties

2001

We study dimensional properties of porous measures on R n . As a corollary of a theorem describing the local structure of nearly uniformly porous measures we prove that the packing dimension of any Radon measure on R n has an upper bound depending on porosity. This upper bound tends to n - 1 as porosity tends to its maximum value.

Packing dimensionCorollaryApplied MathematicsGeneral MathematicsMathematical analysisRadon measurePorosityUpper and lower boundsLocal structurePhysics::GeophysicsMathematicsProceedings of the American Mathematical Society
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Characterisation of upper gradients on the weighted Euclidean space and applications

2020

In the context of Euclidean spaces equipped with an arbitrary Radon measure, we prove the equivalence among several different notions of Sobolev space present in the literature and we characterise the minimal weak upper gradient of all Lipschitz functions.

Pure mathematicsEuclidean spaceApplied MathematicsMathematics::Analysis of PDEsContext (language use)Sobolev spaceLipschitz continuityFunctional Analysis (math.FA)46E35 53C23 26B05differentiaaligeometriaSobolev spaceMathematics - Functional AnalysisMathematics - Analysis of PDEsRadon measureEuclidean geometryFOS: MathematicsWeighted Euclidean spaceDecomposability bundlefunktionaalianalyysiEquivalence (measure theory)MathematicsAnalysis of PDEs (math.AP)
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A DUALITY APPROACH TO THE FRACTIONAL LAPLACIAN WITH MEASURE DATA

2011

We describe a duality method to prove both existence and uniqueness of solutions to nonlocal problems like $$(-\Delta)^s v = \mu \quad \text{in } \mathbb{R}^N,$$ ¶ with vanishing conditions at infinity. Here $\mu$ is a bounded Radon measure whose support is compactly contained in $\mathbb{R}^N$, $N\geq2$, and $-(\Delta)^s$ is the fractional Laplace operator of order $s\in (1/2,1)$.

Pure mathematicsGeneral MathematicsDuality (optimization)fractional laplacianmeasure dataExistenceMeasure (mathematics)Duality solutionsFractional LaplacianOrder (group theory)UniquenessMeasure dataMathematicsFractional Laplacian ; Measure data ; Existence ; Uniqueness ; Duality solutions35B40Mathematical analysisexistenceuniquenessduality solutionsBounded function35K55Radon measurefractional laplacian; uniqueness; duality solutions; measure data; existenceUniquenessFractional LaplacianLaplace operator
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A note on zeroes of real polynomials in $C(K)$ spaces

2008

For real C(K) spaces, we show that being injected in a Hilbert space is a 3-space property. As a consequence, we obtain that, when K does not carry a strictly positive Radon measure, every quadratic continuous homogeneous real-valued polynomial on C(K) admits a linear zero subspace enjoying a property which implies non-separability.

Pure mathematicsPolynomialZero setApplied MathematicsGeneral MathematicsCarry (arithmetic)Mathematical analysisZero (complex analysis)Hilbert spacesymbols.namesakeQuadratic equationRadon measuresymbolsSubspace topologyMathematicsProceedings of the American Mathematical Society
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