摘要:

LetK,S,Tbe subsets of a near-ringR.ThenKis (S,T)-distributive if:s(k1+k2)t=sk1t+sk2t, for eachk1,k2εK,sεS,tεT; andKis (S, T)-d.g. onXifKis (S, X)-distributive andTis contained in the additive subgroup generated byX.This paper considers υ-primitivity and the associated ℑυradicals under various such conditions, particularly whereS, T, andKare powers ofR.Natural examples which illustrate and delimit the theory are given.

ISSN:1607-3606    

DOI:10.1080/16073606.1996.9631995

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Homotopy operations Θ: [ΣY,U] → [ΣY,V] which are natural inYare considered. In particular a technique used in the definition of the Hopf invariant (as treated by Berstein-Hilton) shows that any fibrationp:E→Bwith fiberV, when provided with a homotopy section of Ωp, determines such a homotopy operation [ΣY,E] → [ΣY,V]. More generally, starting from a track class of homotopies α ºf≃ β ºgwe adapt this fibration technique to construct a homotopy operation [ΣY,M(f,g)] → [ΣY,Fα*Fβ] called a Hopf invariant. The intervening fibration in the definition of this Hopf invariant arises via the fiberwise join construction.

ISSN:1607-3606    

DOI:10.1080/16073606.1996.9631996

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

ISSN:1607-3606    

DOI:10.1080/16073606.1996.9631997

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

ISSN:1607-3606    

DOI:10.1080/16073606.1996.9631984

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor