简介:Inthispaper,westudynon-cosemisimpleHopfalgebrasthroughtheirunderlyingcoalgebrastructure.Weintroducetheconceptofthemaximalpointedsubcoalgebra/Hopfsubalgebra.Foranon-cosemisimpleHopfalgebraAwiththeChevalleyproperty,ifitsdiagramisaNicholsalgebra,thenthediagramofitsmaximalpointedHopfsubalgebraisalsoaNicholsalgebra.WhenAisoffinitedimension,weprovideanecessaryandsufficientconditionforA’sdiagramequalingthediagramofitsmaximalpointedHopfsubalgebra.
简介:LetHbeafinite-dimensionalweakHopfalgebraandAaleftH-modulealgebrawithitsinvariantsubalgebraA~H.WeprovethatthesmashproductA#HisanA-ringwithagrouplikecharacter,andgiveacriterionforA#HtobeFrobeniusoverA.UsingthetheoryofA-rings,wemainlyconstructaMoritacontextconnectingthesmashproductA#HandtheinvariantsubalgebraA~H,whichgeneralizesthecorrespondingresultsobtainedbyCohen,FischmanandMontgomery.
简介:Thepurposeofthispaperistopresentsomedualpropertiesofdualcomodule.Itturnsoutthatdualcomodulehasuniversalproperty(cf.Theorem2).Since(()*,()°)isanadjointpair(cf.Theorem3),somenicepropertiesoffunctor()°areobtained.FinelyTheoram4providesthatthecotensorproductisthedualofthetensorproductby(MAN)°≌M°□A.N°.Moreover,theresultHomA(M,N)≌Coma.(N°,M°)isprovedforfiterelatedmodulesM,NoverarefiexivealgebraA.
简介:Inthispaper,westudyaYetter-DrinfeldmoduleVoveraweakHopfalgebraH.AlthoughthecategoryofallleftH-modulesisnotabraidedtensorcategory,wecandefineaYetter-Drinfeldmodule.UsingthisYetter-DrinfeldmodulesV,weconstructNicholsalgebraB(V)overtheweakHopfalgebraH,andaseriesofweakHopfalgebras.Someresultsof[8]aregeneralized.