Se p 20 04 Postnikov Invariants of Crossed Complexes
نویسندگان
چکیده
We determine the Postnikov Tower and Postnikov Invariants of a Crossed Complex in a purely algebraic way. Using the fact that Crossed Complexes are homotopy types for filtered spaces, we use the above " algebraically defined " Postnikov tower and Postnikov invariants to obtain from them those of filtered spaces. We argue that a similar " purely algebraic " approach to Postnikov invariants may also be used in other categories of spaces.
منابع مشابه
Postnikov invariants of crossed complexes
We determine the Postnikov tower and Postnikov invariants of a crossed complex in a purely algebraic way. Using the fact that crossed complexes are homotopy types for filtered spaces, we use the above “algebraically defined” Postnikov tower and Postnikov invariants to obtain from them those of filtered spaces. We argue that a similar “purely algebraic” approach to Postnikov invariants may also ...
متن کاملSe p 20 04 POSTNIKOV PIECES AND B Z / p - HOMOTOPY THEORY
We present a constructive method to compute the cellularization with respect to B m Z/p for any integer m ≥ 1 of a large class of H-spaces, namely all those which have a finite number of non-trivial B m Z/p-homotopy groups (the pointed mapping space map * (B m Z/p, X) is a Postnikov piece). We prove in particular that the B m Z/p-cellularization of an H-space having a finite number of B m Z/p-h...
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The very nature of the so-called Postnikov invariants is carefully studied. Two functors, precisely defined, explain the exact nature of the connection between the category of topological spaces and the category of Postnikov towers. On one hand, these functors are in particular effective and lead to concrete machine computations through the general machine program Kenzo. On the other hand, the ...
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