direct image (functor)
If is a continuous map of topological spaces, and if is the category of sheaves of abelian groups on (and similarly for ), then the direct image functor sends a sheaf on to its direct image on . A morphism of sheaves obviously gives rise to a morphism of sheaves , and this determines a functor.
If is a sheaf of abelian groups (or anything else), so is , so likewise we get direct image functors , where is the category of sheaves of abelian groups on .
|Title||direct image (functor)|
|Date of creation||2013-03-22 12:03:13|
|Last modified on||2013-03-22 12:03:13|
|Last modified by||bwebste (988)|