Search results for "Absolute continuity"

showing 10 items of 34 documents

On $L^p$ resolvent estimates for Laplace-Beltrami operators on compact manifolds

2011

Abstract. In this article we prove Lp estimates for resolvents of Laplace–Beltrami operators on compact Riemannian manifolds, generalizing results of Kenig, Ruiz and Sogge (1987) in the Euclidean case and Shen (2001) for the torus. We follow Sogge (1988) and construct Hadamard's parametrix, then use classical boundedness results on integral operators with oscillatory kernels related to the Carleson and Sjölin condition. Our initial motivation was to obtain Lp Carleman estimates with limiting Carleman weights generalizing those of Jerison and Kenig (1985); we illustrate the pertinence of Lp resolvent estimates by showing the relation with Carleman estimates. Such estimates are useful in the …

Pure mathematicsLaplace transformParametrixApplied MathematicsGeneral MathematicsMathematics::Analysis of PDEsTorusInverse problemAbsolute continuityMathematics::Spectral TheoryMathematics - Analysis of PDEsLaplace–Beltrami operatorEuclidean geometryFOS: Mathematics[MATH.MATH-AP]Mathematics [math]/Analysis of PDEs [math.AP]ResolventMathematicsAnalysis of PDEs (math.AP)
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On the inverse absolute continuity of quasiconformal mappings on hypersurfaces

2018

We construct quasiconformal mappings $f\colon \mathbb{R}^{3} \rightarrow \mathbb{R}^{3}$ for which there is a Borel set $E \subset \mathbb{R}^2 \times \{0\}$ of positive Lebesgue $2$-measure whose image $f(E)$ has Hausdorff $2$-measure zero. This gives a solution to the open problem of inverse absolute continuity of quasiconformal mappings on hypersurfaces, attributed to Gehring. By implication, our result also answers questions of V\"ais\"al\"a and Astala--Bonk--Heinonen.

Pure mathematicsMathematics::Complex VariablesMathematics - Complex VariablesGeneral MathematicsImage (category theory)Open problem010102 general mathematicsHausdorff spaceZero (complex analysis)InverseAbsolute continuityLebesgue integration01 natural sciences30C65 30L10funktioteoriasymbols.namesakeFOS: MathematicssymbolsMathematics::Metric GeometryComplex Variables (math.CV)0101 mathematicsBorel setMathematics
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Some new results on integration for multifunction

2018

It has been proven in previous papers that each Henstock-Kurzweil-Pettis integrable multifunction with weakly compact values can be represented as a sum of one of its selections and a Pettis integrable multifunction. We prove here that if the initial multifunction is also Bochner measurable and has absolutely continuous variational measure of its integral, then it is a sum of a strongly measurable selection and of a variationally Henstock integrable multifunction that is also Birkhoff integrable.

Pure mathematicsSelection (relational algebra)Integrable systemApplied MathematicsGeneral Mathematics010102 general mathematicsMultifunction set-valued Pettis integral set-valued variationally Henstock and Birkhoff integrals selectionselectionAbsolute continuity01 natural sciencesMeasure (mathematics)Set-valued Pettis integralFunctional Analysis (math.FA)28B20 26E25 26A39 28B05 46G10 54C60 54C65Mathematics - Functional Analysisset-valued Pettis integral010101 applied mathematicsMultifunctionSettore MAT/05 - Analisi MatematicaHenstock and Birkhoff integralsFOS: Mathematicsset-valued variationally0101 mathematicsSet-valued variationally henstock and birkhoff integralMathematicsRicerche di Matematica
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Absolutely continuous variational measures of Mawhin's type

2011

Abstract In this paper we study absolutely continuous and σ-finite variational measures corresponding to Mawhin, F- and BV -integrals. We obtain characterization of these σ-finite variational measures similar to those obtained in the case of standard variational measures. We also give a new proof of the Radon-Nikodým theorem for these measures.

Pure mathematicsVariational measure Mawhin integral Radon-Nikodym theoremSettore MAT/05 - Analisi MatematicaGeneral MathematicsCalculusAlgebra over a fieldCharacterization (mathematics)Absolute continuityMathematics
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Classes of regular Sobolev mappings

2008

We prove that a slight modification of the notion of α-absolute continuity introduced in [D. Bongiorno, Absolutely continuous functions in Rn, J. Math. Anal. Appl. 303 (2005) 119–134] is equivalent to the notion of n, λ-absolute continuity given by S. Hencl in [S. Hencl, On the notions of absolute continuity for functions of several variables, Fund. Math. 173 (2002) 175–189].

Settore MAT/05 - Analisi MatematicaAbsolute continuitySobolev space
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THE HKr-INTEGRAL IS NOT CONTAINED IN THE Pr-INTEGRAL

2022

We compare a Perron-type integral with a Henstock-Kurzweiltype integral, both having been introduced to recover functions from their generalized derivatives defined in the metric Lr. We give an example of an HKr-integrable function which is not Pr-integrable, thereby showing that the first integral is strictly wider than the second one.

Settore MAT/05 - Analisi MatematicaHenstock-Kurzweil-type integralgeneralized absolute continuityDerivative in LrPerron-type integral
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Regular subclasses in the Sobolev space W_{loc}^{1,n}

2009

Westudy some slight modifications of the class AC^n introduced in [D. Bongiorno, Absolutely continuous functions in Rn, J. Math. Anal. and Appl. 303 (2005) 119 134]. In particular we prove that the classes introduced in [C. Di Bari, C. Vetro, A remark on absolutely continuous functions in R^n, Rend. Circ. Matem. Palermo 55 (2006) 296 304] are independent by and contain properly the class AC^n.

Settore MAT/05 - Analisi MatematicaSobolev space Absolute continuity.
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On the Hencl's notion of absolute continuity

2009

Abstract We prove that a slight modification of the notion of α-absolute continuity introduced in [D. Bongiorno, Absolutely continuous functions in R n , J. Math. Anal. Appl. 303 (2005) 119–134] is equivalent to the notion of n, λ-absolute continuity given by S. Hencl in [S. Hencl, On the notions of absolute continuity for functions of several variables, Fund. Math. 173 (2002) 175–189].

Sobolev spacePure mathematicsContinuous functionApplied MathematicsCalculusAbsolute continuityAbsolute continuitySobolev spaceAnalysisModulus of continuityMathematics
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Applications de type Lasota–Yorke à trou : mesure de probabilité conditionellement invariante et mesure de probabilité invariante sur l'ensemble des …

2003

Abstract Let T :I→I be a Lasota–Yorke map on the interval I, let Y be a nontrivial sub-interval of I and g 0 :I→ R + , be a strictly positive potential which belongs to BV and admits a conformal measure m. We give constructive conditions on Y ensuring the existence of absolutely continuous (w.r.t. m) conditionally invariant probability measures to nonabsorption in Y. These conditions imply also existence of an invariant probability measure on the set X∞ of points which never fall into Y. Our conditions allow rather “large” holes.

Statistics and ProbabilityDiscrete mathematicsPure mathematicsHausdorff dimensionErgodic theoryInvariant measureInterval (mathematics)Statistics Probability and UncertaintyInvariant (mathematics)Absolute continuityMeasure (mathematics)Probability measureMathematicsAnnales de l'Institut Henri Poincare (B) Probability and Statistics
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THE MINIMIZING TOTAL VARIATION FLOW WITH MEASURE INITIAL CONDITIONS

2004

In this paper we obtain existence and uniqueness of solutions for the Cauchy problem for the minimizing total variation flow when the initial condition is a Radon measure in ℝN. We study limit solutions obtained by weakly approximating the initial measure μ by functions in L1(ℝN). We are able to characterize limit solutions when the initial condition μ=h+μs, where h∈L1(ℝN)∩L∞(ℝN), and μs=αℋk⌊ S,α≥0,k is an integer and S is a k-dimensional manifold with bounded curvatures. In case k<N-1 we prove that the singular part of the solution does not move, it remains equal to μs for all t≥0. In particular, u(t)=δ0 when u(0)=δ0. In case k=N-1 we prove that the singular part of the limit solution …

Strong solutionsNonlinear parabolic equationsApplied MathematicsGeneral MathematicsBounded functionRadon measureMathematical analysisInitial value problemEntropy (information theory)UniquenessAbsolute continuityMathematicsCommunications in Contemporary Mathematics
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