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Relative Projectivity and Ideals in Cohomology Rings

✍ Scribed by Jon F. Carlson; Chuang Peng

Publisher
Elsevier Science
Year
1996
Tongue
English
Weight
219 KB
Volume
183
Category
Article
ISSN
0021-8693

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✦ Synopsis

In this paper we explore one aspect of the relationship between group cohomology and representation theory. For a finite group G and a field k in characteristic Ž . p)0, ideals in the cohomology ring H * G, k can sometimes be characterized by exact sequences of kG-modules in much the same way that elements of Ext are k G classically represented by exact sequences. Furthermore the maps on the stable category which represent the exact sequences have functorial properties which mimic the structure of the ideas in the ring. The natural setting for this study is the relative homological algebra for the module category, relative to the subcategory generated by a single module using the tensor product operation.

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