Extensions of group retractions
نویسندگان
چکیده
منابع مشابه
Group Actions and Group Extensions
In this paper we study finite group extensions represented by special cohomology classes. As an application, we obtain some restrictions on finite groups which can act freely on a product of spheres or on a product of real projective spaces. In particular, we prove that if (Z/p)r acts freely on (S1)k , then r ≤ k.
متن کاملRetractions of Chaotic Buchdahi Space and Their Chaotic Homology Group
The purpose of this paper is to give a combinatorial characterization and also construct representations of the chaotic homology groups of the chaotic submanifolds of chaotic Buchdahi space by using some geometrical transformations. The chaotic homotopy groups of the limit for chaotic Buchdahi space are presented. The chaotic homology groups of some types of chaotic geodesics in chaotic Buchdah...
متن کاملCohomology of Group Extensions
Introduction. Let G be a group, K an invariant subgroup of G. The purpose of this paper is to investigate the relations between the cohomology groups of G, K, and G/K. As in the case of fibre spaces, it turns out that such relations can be expressed by a spectral sequence whose term E2 is HiG/K, HiK)) and whose term Em is the graduated group associated with i7(G). This problem was first studied...
متن کاملSpeedups of ergodic group extensions
We prove that for all ergodic extensions S1 of a transformation by a locally compact second countable group G, and for all G-extensions S2 of an aperiodic transformation, there is a relative speedup of S1 that is relatively isomorphic to S2. We apply this result to give necessary and sufficient conditions for two ergodic n-point or countable extensions to be related in this way.
متن کاملKazhdan Constants of Group Extensions
We give bounds on Kazhdan constants of abelian extensions of (finite) groups. As a corollary, we improved known results of Kazhdan constants for some meta-abelian groups and for the relatively free group in the variety of p-groups of lower p-series of class 2. Furthermore, we calculate Kazhdan constants of the tame automorphism groups of the free nilpotent groups.
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: International Journal of Mathematics and Mathematical Sciences
سال: 1980
ISSN: 0161-1712,1687-0425
DOI: 10.1155/s016117128000052x