Search results for "Number"

showing 10 items of 3939 documents

On Higgs bundles over Shimura varieties of ball quotient type

2016

We prove the generic exclusion of certain Shimura varieties of unitary and orthogonal types from the Torelli locus. The proof relies on a slope inequality on surface fibration due to G. Xiao, and the main result implies that certain Shimura varieties only meet the Torelli locus in dimension zero.

Pure mathematicsMathematics - Number TheoryApplied MathematicsGeneral MathematicsMathematics::Number Theory010102 general mathematicsFibrationQuotient type01 natural sciencesUnitary stateMathematics::Algebraic TopologyMathematics - Algebraic GeometryMathematics::Algebraic GeometryFOS: MathematicsHiggs bosonNumber Theory (math.NT)Ball (mathematics)0101 mathematicsMathematics::Representation TheoryAlgebraic Geometry (math.AG)Mathematics
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Transcendental lattices of some K 3-surfaces

2008

In a previous paper, (S2), we described six families of K3-surfaces with Picard- number 19, and we identified surfaces with Picard-number 20. In these notes we classify some of the surfaces by computing their transcendental lattices. Moreover we show that the surfaces with Picard-number 19 are birational to a Kummer surface which is the quotient of a non-product type abelian surface by an involution.

Pure mathematicsMathematics::Algebraic GeometryGeneral MathematicsMathematical analysisAbelian surfaceTranscendental numberKummer surfaceQuotientMathematicsMathematische Nachrichten
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On a Theorem of Greuel and Steenbrink

2017

A famous theorem of Greuel and Steenbrink states that the first Betti number of the Milnor fibre of a smoothing of a normal surface singularity vanishes. In this paper we prove a general theorem on the first Betti number of a smoothing that implies an analogous result for weakly normal singularities.

Pure mathematicsMathematics::Algebraic GeometryGeneral theoremSingularityBetti numberGravitational singularityNormal surfaceMathematics::Algebraic TopologySmoothingMathematics
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Stable Images and Discriminants

2020

We show that the discriminant/image of a stable perturbation of a germ of finite \(\mathcal {A}\)-codimension is a hypersurface with the homotopy type of a wedge of spheres in middle dimension, provided the target dimension does not exceed the source dimension by more than one. The number of spheres in the wedge is called the discriminant Milnor number/image Milnor number. We prove a lemma showing how to calculate this number, and show that when the target dimension does not exceed the source dimension, the discriminant Milnor number and the \(\mathcal {A}\)-codimension obey the “Milnor–Tjurina relation” familiar in the case of isolated hypersurface singularities. This relation remains conj…

Pure mathematicsMathematics::Algebraic GeometryHypersurfaceDiscriminantHomotopyPerturbation (astronomy)SPHERESGravitational singularityMathematics::Algebraic TopologyWedge (geometry)MathematicsMilnor number
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Projecting 4-folds from G(1, 5) to G(1, 4)

2002

We study 4-dimensional subvarieties of the Grassmannian G(1,5) with singular locus of dimension at most 1 that can be isomorphically projected to G(1,4).

Pure mathematicsMathematics::Algebraic GeometryNumber theoryGeneral MathematicsGrassmannianGeometryAlgebraic geometrySettore MAT/03 - GeometriaLocus (mathematics)Computer Science::DatabasesMathematicsGrassmannians projections
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Equidistribution and Counting of Quadratic Irrational Points in Non-Archimedean Local Fields

2019

We use these results to deduce equidistribution and counting results of quadratic irrational elements in non-Archimedean local fields.

Pure mathematicsMathematics::Dynamical SystemsMathematics::Number TheoryQuadratic irrationalMathematics
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Banach partial *-algebras: an overview

2019

A Banach partial $*$-algebra is a locally convex partial $*$-algebra whose total space is a Banach space. A Banach partial $*$-algebra is said to be of type (B) if it possesses a generating family of multiplier spaces that are also Banach spaces. We describe the basic properties of these objects and display a number of examples, namely, $L^p$-like function spaces and spaces of operators on Hilbert scales or lattices. Finally we analyze the important cases of Banach quasi $*$-algebras and $CQ^*$-algebras.

Pure mathematicsMathematics::Functional AnalysisAlgebra and Number Theorypartial inner product spacesPartial *-algebra Banach partial *-algebra CQ*-algebra partial inner product space operators on Hilbert scale.Partial algebraPartial *-algebraspartial $*$-algebraCQ*-algebraspartial inner product spaceSettore MAT/05 - Analisi Matematica$CQ^*$-algebraBanach partial *-algebrasoperators on Hilbert scaleBanach partial $*$-algebra46J1008A55Analysis47L60Mathematics
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"Fixed Point Theorems for '?, ?'Contractive maps in Weak nonArchimedean Fuzzy Metric Spaces and Application"

2011

The present study introduce the notion of (ψ, ϕ)-Contractive maps in weak non-Archimedean fuzzy metric spaces to derive a common fixed point theorem which complements and extends the main theorems of [C.Vetro, Fixed points in weak non-Archimedean fuzzy metric spaces, Fuzzy Sets and System, 162 (2011), 84-90] and [D.Mihet, Fuzzy ψ-contractive mappings in non-Archimedean fuzzy metric spaces, Fuzzy Sets and System, 159 (2008) 739-744]. We support our result by establishing an application to product spaces.

Pure mathematicsMathematics::General MathematicsComputer scienceInjective metric spaceFuzzy setFixed-point theoremNon-Archimedean fuzzy metric spaceProduct metricT-normFuzzy subalgebraFixed pointCommon fixed pointFuzzy logic ϕ)-contractive mapsConvex metric spaceSettore MAT/05 - Analisi MatematicaFuzzy mathematicsFuzzy numberMetric mapInternational Journal of Computer Applications
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Principal Values of Cauchy Integrals, Rectifiable Measures and Sets

1991

The extensive studies started by A. P. Calderon in the sixties and continued by many authors up today have revealed that the Cauchy integrals $$ {C_{\Gamma }}f(z) = \int_{\Gamma } {\frac{{f\left( \zeta \right)d\zeta }}{{\zeta - z}}} $$ behave very well on sufficiently regular, not necessarily smooth, curves F, see [CCFJR], [D] and [MT].

Pure mathematicsMathematics::Number TheoryResidue theoremPrincipal valueCauchy principal valueCauchy distributionCauchy's integral theoremMathematics
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Decomposition numbers and local properties

2020

Abstract If G is a finite group and p is a prime, we give evidence that the p-decomposition matrix encodes properties of p-Sylow normalizers.

Pure mathematicsMatrix (mathematics)Finite groupAlgebra and Number TheoryCharacter table010102 general mathematics0103 physical sciencesDecomposition (computer science)010307 mathematical physics0101 mathematics01 natural sciencesPrime (order theory)MathematicsJournal of Algebra
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