# nLab cohomology ring

cohomology

### Theorems

Similar to the discussion at cohomology group, a cohomology set ${H}_{*}\left(X,A\right)$ may have the strcuture of a ring if the coefficient object $A$ has suitable properties.

In particular for $H=$Top, ${H}_{*}\left(X,A\right)$ is a ring when $A$ is an ${E}_{\infty }$-ring.

Revised on November 15, 2011 13:44:40 by Urs Schreiber (131.174.40.227)