Comultiplication and suspension
نویسنده
چکیده
We prove the conjecture of Berstein, Hilton, and Ganea that an (n I)-connected CW-complex X with dim X < k(n 2) + 3 which has a co-Ak_,-space structure desuspends. Moreover, we show the following dual of a result of Segal: given a cosimplicial space Y, which is special in the sense that the canonical maps Vz’, Yr + k;, are homotopy equivalences and Yl is 2-connected then there is a functorial desuspension of Y,.
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