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Cohomology ring

0:51

Cohomology Rings of Finite Groups With an Appendix Calculations of Cohomology Rings of Groups of Ord

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Collin Roberts - The cohomology ring of a finite abelian group

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Mathematics: Why does "dimension" of the generator matter for cohomology rings?

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Ring mathematics

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Cohomology

In mathematics, specifically algebraic topology, the cohomology ring of a topological space X is a ring formed from the cohomology groups of X together with the cup product serving as the ring multiplication. Here 'cohomology' is usually understood as singular cohomology, but the ring structure is also present in other theories such as de Rham cohomology. It is also functorial: for a continuous mapping of spaces one obtains a ring homomorphism on cohomology rings, which is contravariant.