ISSN:0092-7872    

DOI:10.1080/00927879808826232

出版商:Gordon and Breach Science Publishers Ltd.    

年代:1998

数据来源: Taylor

摘要:

Given a ringRand a class χ of rightR-modules, a rightR-moduleMcan be an extending module relative to χ in two different ways. Various general properties of such extending modules are given and, in case of specific classes ofR-modules, we characterize them.

ISSN:0092-7872    

DOI:10.1080/00927879808826233

出版商:Gordon and Breach Science Publishers Ltd.    

年代:1998

数据来源: Taylor

摘要:

The derivation algebraLof the associative algebra Cq[X,Y,X-1,Y-1] (qn:≠1,n∈ N)and the automorphism group AutLofLare given.

ISSN:0092-7872    

DOI:10.1080/00927879808826234

出版商:Gordon and Breach Science Publishers Ltd.    

年代:1998

数据来源: Taylor

摘要:

We investigate internal pregroupoid structures in congruence modular and congruence distributive varieties.

ISSN:0092-7872    

DOI:10.1080/00927879808826235

出版商:Gordon and Breach Science Publishers Ltd.    

年代:1998

数据来源: Taylor

摘要:

Here we study the Hilbert function of a Cohen-Macaulay homogeneous domain over an algebraically closed field of positive characteristic. The main tool (and an essential part of the main geometrical results) is the study of the Hilbert function of a general hyperplane sectionX⊂Prof an integral curveC⊂Pr+1, which is pathological in some sense. In §1, we study the case whenCis a strange curve, i.e., all tangent lines toCat its simple points pass through a fixed point υ∈Pr+1. In §2, we give more refined results under the assumption that the Trisecant Lemma fails forC, i.e., any line spanned by two points ofCcontains one more point ofC.

ISSN:0092-7872    

DOI:10.1080/00927879808826236

出版商:Gordon and Breach Science Publishers Ltd.    

年代:1998

数据来源: Taylor

摘要:

Let (R,m) be a noetherian local ring of prime characteristic andFR(-) be the Frobenius functor. We will show that for all finiteR-modulesMthere is ann∈ N (depending onM) such that the fundamental theorem for modules over principal domains holds fori.e. there arer, s∈ N and elementsif and only ifRis geometrically unibranch in the sense of Grothendieck [2] and dimR≤ 1.For exampleRis geometrically unibranch, if it is complete andR/mis an algebraically closed field.

ISSN:0092-7872    

DOI:10.1080/00927879808826237

出版商:Gordon and Breach Science Publishers Ltd.    

年代:1998

数据来源: Taylor

ISSN:0092-7872    

DOI:10.1080/00927879808826238

出版商:Gordon and Breach Science Publishers Ltd.    

年代:1998

数据来源: Taylor

摘要:

We prove that, for every natural numbern, there exists a unital semisimple Banach star algebraAand a closed star subalgebraBof the centre ofA, different from C, such that the globalB-homological dimension and theB-homological bidimension ofAare both equal ton. The algebrasAandBcan be taken to be function algebras.

ISSN:0092-7872    

DOI:10.1080/00927879808826239

出版商:Gordon and Breach Science Publishers Ltd.    

年代:1998

数据来源: Taylor

摘要:

Inspired by a result in [Ga], we locate three integer forms ofFq[SL(n+ 1)] overk[q,q-1] wih a presentation by generators and relations, which forq=1 specialize toU(𝔥)), where 𝔥 is the Lie bialgebra of the Poisson Lie group dual toSL(n+1). In sight of this we prove two PBW-like theorems forFq[SL(n+ 1)], both related to the classical PBW theorem for U(𝔥).

ISSN:0092-7872    

DOI:10.1080/00927879808826240

出版商:Gordon and Breach Science Publishers Ltd.    

年代:1998

数据来源: Taylor

摘要:

We study functional identities of degreem. As an application of obtained results, we describe additive mappingsfi:A→Aof a prime ring A satisfying a functional identity of the formProvided thatAis not algebraic of bounded degree ≤nover the extended centroid. A number of results onk-commuting additive mappings and commuting traces ofm-additive mappings, obtained earlier, are special cases of our ones.

ISSN:0092-7872    

DOI:10.1080/00927879808826241

出版商:Gordon and Breach Science Publishers Ltd.    

年代:1998

数据来源: Taylor