Fe b 20 00 INTERCHANGING HOMOTOPY LIMITS AND COLIMITS IN CAT
نویسندگان
چکیده
Here HOM is the functor category, π∗ is induced by the natural projection π : hocolimI C −→ I, 0 is the category with only one map and id maps the only object of 0 to the identity functor. A reason for using the above definitions is that taking nerves one recovers the usual homotopy (co)limits for simplicial sets, up to homotopy in the case of hocolim ([T]) and up to isomorphism in the case of holim ([L]). Before we state the main result of this paper, we need a definition.
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