منابع مشابه
O ct 2 00 0 PERIODIC COMPLEXES AND GROUP ACTIONS
In this paper we show that the cohomology of a connected CW–complex is periodic if and only if it is the base space of an orientable spherical fibration with total space that is homotopically finite dimensional. As applications we characterize those discrete groups that act freely and properly on R × S; we construct non–standard free actions of rank two simple groups on finite complexes Y ≃ S ×...
متن کامل. A T ] 1 2 Ju l 2 00 1 PERIODIC COMPLEXES AND GROUP ACTIONS
In this paper we show that the cohomology of a connected CW–complex is periodic if and only if it is the base space of a spherical fibration with total space that is homotopically finite dimensional. As applications we characterize those discrete groups that act freely and properly on R×S; we construct non–standard free actions of rank two simple groups on finite complexes Y ≃ S × S; and we pro...
متن کاملGroup Actions on Algebraic Cell Complexes
We establish an algebraic version of the classical result that a G-map f between G-complexes which restricts to a homotopy equivalence fH on H-fixed sets for all subgroups H of G is a G-homotopy equivalence. This is used to give an alternative proof of a theorem of Bouc. We also include a number of illustrations and applications.
متن کاملBraid Group Actions via Categorified Heisenberg Complexes
We construct categorical braid group actions from 2-representations of a Heisenberg algebra. These actions are induced by certain complexes which generalize spherical (Seidel-Thomas) twists and are reminiscent of the Rickard complexes defined by Chuang-Rouquier. Conjecturally, one can relate our complexes to Rickard complexes using categorical vertex operators.
متن کاملGroup 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 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: The Annals of Mathematics
سال: 2001
ISSN: 0003-486X
DOI: 10.2307/3062102