A universal space for plus-constructions

Citations of this article
Mendeley users who have this article in their library.


We exhibit a two-dimensional, acyclic, Eilenberg-Mac Lane space W such that, for every space X, the plus-construction X+ with respect to the largest perfect subgroup of π1(X) coincides, up to homotopy, with the W-nullification of X; that is, the natural map X → X+ is homotopy initial among maps X → Y where the based mapping space map*(W, Y) is weakly contractible. Furthermore, we describe the effect of W -nullification for any acyclic W, and show that some of its properties imply, in their turn, the acyclicity of W. © 1999 Elsevier Science Ltd. All rights reserved.




Berrick, A. J., & Casacuberta, C. (1999). A universal space for plus-constructions. Topology, 38(3), 467–477. https://doi.org/10.1016/S0040-9383(97)00073-6

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free