Two remarks on Wall's D2 problem

  title={Two remarks on Wall's D2 problem},
  author={Ian Hambleton},
  journal={Mathematical Proceedings of the Cambridge Philosophical Society},
  pages={361 - 368}
  • I. Hambleton
  • Published 28 August 2017
  • Mathematics
  • Mathematical Proceedings of the Cambridge Philosophical Society
Abstract If a finite group G is isomorphic to a subgroup of SO(3), then G has the D2-property. Let X be a finite complex satisfying Wall's D2-conditions. If π1(X) = G is finite, and χ(X) ≥ 1 − def(G), then X ∨ S2 is simple homotopy equivalent to a finite 2-complex, whose simple homotopy type depends only on G and χ(X). 
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