|Título inglés||Weakly additive cohomology.|
|Título español||Cohomología debilmente aditiva.|
|Organización||Dep. Math. Univ. California-Berkeley, Berkeley (California), Estados Unidos|
|Publicación||1990, 34 (1): 145-150, 5 Ref.|
|Tipo de documento||articulo|
|Resumen inglés||In this paper the concept of weakly additive cohomology theory is introduced as a variant of the known concept of additive cohomology theory. It is shown that for a closed A in X the singular homology of the pair (X, X-A) (with some fixed cohomology group) regarded as a furcter of A is a weakly additive cohomology theory on any collectionwise normal space X. Furthermore, every compactly supported cohomology theory is weakly additive.
The main result is a comparison theorem for two cohomology theories on X both of which are additive or both of which are weakly additive which recomposes the previously known comparison theorems.
|Palabras clave español||Cohomología|
|Acceso al artículo completo|