Cohomology
From Conservapedia
This is an old revision of this page, as edited by CSGuy (Talk | contribs) at 21:07, November 17, 2008. It may differ significantly from current revision.
In category theory, the cohomology of an exact sequence studies the relationship between the cokernels and coimages, when it is possible to take their quotient. Cohomology is the category-theoretic dual of homology.
Well-known examples include de Rham cohomology in differential geometry, elliptic curve cohomology, and hyperbolic cohomology of infinite Abelian groups.