Cohomology groups do not determine homotopy type

ID: cohomology-groups-do-not-determine-homotopy-type

The torus and the wedge sum both have integral cohomology in degrees zero, one and two. Their fundamental groups differ: the torus has , while the wedge has the nonabelian free group on two generators. Thus even compact finite cell complexes can have the same additive cohomology without being homotopy equivalent.

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