简介:LetMbeacompactminimalhypersurfaceofsphereSn+1(1).Let(M)beH(r)-torusofsphereSn+1(1).AssumetheyhavethesameconstantmeancurvatureH,theresultin[1]isthatifSpec0(M,g)=Spec0((M),g),thenfor3≤n≤6,r2≤n-1/norn≥6,r2≥n-1,thenMisisometricto(M).Weimprovedtheresultandprovethat:ifSpec0(M,g)=Spec0((M),g),thenMisisometricto(M).Generally,ifSpecp(M,g)=Specp((M),g),herepisfixedandsatisfiesthatn(n-1)≠6p(n-p),thenMisisometricto(M).
简介:Anewmethodwasproposedforconstructingtotalvariationdiminishing(TVD)upwindschemesinconservationforms.Twolimiterswereusedtopreventnon-physicaloscillationsacrossdiscontinuity.BothlimiterscanensurethenonlinearcompactschemesTVDproperty.TwocompactTVD(CTVD)schemesweretested,oneisthird-orderaccuracy,andtheotherisfifth-order.Theperformanceofthenumericalalgorithmswasassessedbyone-dimensionalcomplexwavesandRiemannproblems,aswellasatwo-dimensionalshock-vortexinteractionandashock-boundaryflowinteraction.Numericalresultsshowtheirhigh-orderaccuracyandhighresolution,andlowoscillationsacrossdiscontinuities.更多还原
简介:THEGENERALIZEDEINSTEINRELATIONONACOMPACT ORIENTABLERIMANNIANMANIFOLDFangHaito(方海涛);GongGuanglu(龚光鲁)(DepartmentofAppliedMathem...
简介:ThispaperintroducesaunifiedoperatortheoryapproachtotheabstractFourieranalysisoverhomogeneousspacesofcompactgroups.LetGbeacompactgroupandHbeaclosedsubgroupofG.LetG/HbetheleftcosetspaceofHinGandμbethenormalizedG-invariantmeasureonG/HassociatedtotheWeil'sformula.Then,wepresentageneralizedabstractframeworkofFourieranalysisfortheHilbertfunctionspaceL~2(G/H,μ).
简介:这份报纸介绍概括Riesz操作符的概念和概括Riesz操作符的西方分解的定义的一个一般操作符的概括韦斯特分解的概念,并且证明下列三个语句在一个一般Banach空格是相等的:(a)每个概括Riesz操作员有概括韦斯特分解;每个操作员使Stampfli强壮的(b)定理真;(c)每个操作员有Apostol鈥檚协议修正。关键词Banach空间-概括Riesz操作员-概括韦斯特分解-紧缩的修正先生(2000)题目分类47A10-47A11-47A53由中国(10471025)的国家自然科学基础支持了,福建省(Z0511019)和福建省(JA04170)的教育系的基础的国家科学基金
简介:Inthispaper,thenotionoftheboundedcompactapproximationproperty(BCAP)ofapair[Banachspaceanditssubspace]isusedtoprovethatifXisaclosedsubspaceofL∞withtheBCAP,thenL∞/XhastheBCAP.WealsoshowthatX*hastheλ-BCAPwithconjugateoperatorsifandonlyifthepair(X,Y)hastheλ-BCAPforeachfinitecodimensionalsubspaceY∈X.LetMbeaclosedsubspaceofXsuchthatM⊥iscomplementedinX*.IfXhasthe(bounded)approximationpropertyoforderp,thenMhasthe(bounded)approximationpropertyoforderp.
简介:这份报纸给有限维的无法缩减的操作员的概念((FDI)操作员)并且无限的维的无法缩减的操作员((IDI)操作员)。讨论关系(FDI)操作员,(IDI)操作员和强烈无法缩减的操作员((SI)操作员)并且说明操作员的三个班的一些性质。为有上面的三角形的操作员矩阵的形式的操作员的有限维的irreducibility的一些足够的条件被给。这份报纸证明有一个单条系列的每个操作符是小紧缩的不安一(FDI)在每围住的线性操作符T能被操作符接近在的可分离的Banach空格和表演(FDI)的操作员关于强壮操作员的拓扑学和每个紧缩的操作符K罐头的(X)由操作符接近了在(FDI)关于有一个Schauder基础的Banach空格X上的标准拓扑学的(X),在此(FDI)(X):={TB(X):T=i=1kTi,Ti(FDI),k}。
简介:TheauthorgivesanoptimumestimateofthefirsteigenvalueofacompactRiemannianmanifold.ItisshownthatletMbeacompactRiemannianmanifold,thenthefirsteigenvalueλ1oftheLaplaceoperatorofMsatisfiesα1+max{0,-(n-1)K}≥π2/d2wheredisthediameterofMand(n-1)KisthenegativelowerboundoftheRiccicurvatureofM.
简介:WefindalowerboundfortheessentialnormofthedifferenceoftwocompositionoperatorsactingonH2(BN)orAs2(BN)(s>1).Thisresultplaysanimportantroleinprovinganecessaryandsufficientconditionforthedifferenceoflinearfractionalcompositionoperatorstobecompact,whichanswersaquestionposedbyMacCluerandWeirin2005.更多还原
简介:为>1,让d在bidisk和一项复杂措施上表示加权的Lebesgue措施令人满意一些Carleson类型条件。在这份报纸,我们为Toeplitz操作员$T_显示出一个足够、必要的条件{\bar\mu}在加权的Bergman空间L上要跳或压缩的^\alpha$一1(d)。
简介:ThispapeerstudiestheknowndensitytheoremofArrow-Barankin-Blackwell.Thefollowingmainresultisobtained:IfXisaHausdorfflocallyconvexTopologicalspaceandCbelongtoXisaclosedconvexconewithboundedbase,thenforeverynonemptyweaklycompactconvexsubsetA,thesetofpositiveproperefficientpointsofAisdenseinthesetofefficientpointsofA.
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简介:<正>LetMbeacompactminimalsurfaceinS3.Y.J.Hsuprovedthatif‖S‖2≤2(21/2π,thenMiseithertheequatorialsphereortheCliffordtorus,where5"isthesquareofthelengthofthesecondfundamentalformofM,‖·‖2denotestheL2-normonM.Inthispaper,wegeneralizeHsu’sresulttoanycompactsurfacesinS3withconstantmeancurvature.