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LSpice
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When is the classifying space of a group/H-space rationally equivalent to a product of Eilenberg-Maclane spaces?

The MO-question asks why the classifying space of a group is not necessarily rationally a product of Eilenberg–MacLane spaces. I am looking for classes of examples of connected topological groups/connected associative H-spaces such that their classifying space happens to be rationally a product of Eilenberg–MacLane spaces. I'm the most interested in examples of groups that have an interesting action on a closed manifold.

So far I know that this holds for

  • compact groups, because the cohomology ring of their classifying space is a polynomial ring
  • Lie groups since they are homotopy equivalent to their maximal compact subgroup
  • the identity component of the homotopy automorphisms of an aspherical space, because its classifying space is already an Eilenberg–MacLane space.
ThorbenK
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