2015/07/06 by Hirschhorn, Philip S.
#Algebraic Topology (math.AT) #FOS: Mathematics
paper · doi:10.48550/arxiv.1507.01627
We carefully present an elementary proof of the well known theorem that each homotopy group (or, in degree zero, pointed set) of the inverse limit of a tower of fibrations maps naturally onto the inverse limit of the homotopy groups (or, in degree zero, pointed sets) of the spaces in the tower, with kernel naturally isomorphic to lim1 of the tower of homotopy groups of one dimension higher.