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Purity and injectivity in accessible categories

✍ Scribed by Michel Hébert

Publisher
Elsevier Science
Year
1998
Tongue
English
Weight
336 KB
Volume
129
Category
Article
ISSN
0022-4049

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✦ Synopsis

We introduce a strengthening of the concept of purity, which may be more appropriate in the context of accessible categories (and which we prove to be equivalent to the usual one in locally presentable categories). We then use it to obtain a characterization of (cone) injectivity classes which, in particular, provides a solution to the corresponding problem of Fuchs (in the context of abelian groups) which avoids the set-theoretical assumptions of the Aditmek-Rosice solution.

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