The ring of stable homotopy classes of self-maps of A(n,2)-polyhedra

Published: 01 Mar 2021, Last Modified: 29 Apr 2026Topology and its ApplicationsEveryoneRevisionsBibTeXCC BY-SA 4.0
Abstract: We raise the problem of realisability of rings as {X,X} the ring of stable homotopy classes of self-maps of a space X. By focusing on A n 2-polyhedra, we show that the direct sum of three endomorphism rings of abelian groups, one of which must be free, is realisable as {X,X} modulo the acyclic maps. We also show that F p 3 is not realisable in the setting of finite type A n 2-polyhedra, for p any prime.
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