| Date: |
1990 |
| Abstract: |
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 pasi (X, X - A) (with some fixed coefficient gropu) regarded as a furcter of A is a weakly additive cohomology theory on any collectionwise normal space X. Fiirthermore, 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 ercomposses the previously known compauson theorems. |
| Rights: |
Aquest material està protegit per drets d'autor i/o drets afins. Podeu utilitzar aquest material en funció del que permet la legislació de drets d'autor i drets afins d'aplicació al vostre cas. Per a d'altres usos heu d'obtenir permís del(s) titular(s) de drets.  |
| Language: |
Anglès |
| Document: |
Article ; recerca ; Versió publicada |
| Published in: |
Publicacions matemàtiques, Vol. 34, Num. 1 (1990) , p. 145-150, ISSN 2014-4350 |
guest ::
