函子类别的补全和可访问性

IF 0.7 2区 数学 Q2 MATHEMATICS
Simon Henry
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引用次数: 0

摘要

我们研究了在什么条件下函子范畴CI的κ-Ind补全等价于从I到C的κ-Ind补全的函子范畴。一个已发表的结果表明,这对于任何柯西完备范畴C和κ-小范畴I都是成立的,但我们证明了一般情况下并非如此。我们证明了两个结果,这两个结果似乎涵盖了我们可以在文献中找到的这个错误定理的所有应用:如果C有κ-小的极限并且I是κ-小,或者如果C是一个任意范畴并且I是有充分根据并且κ-小,则结果成立。在这两种情况下,我们证明了条件是最优的,即当且仅当I满足给定的假设时,结果对所有C都成立。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
Ind-completion and accessibility of functor categories
We investigate under which conditions the κ-Ind completion of a functor category CI is equivalent to the category of functors from I to the κ-Ind completion of C. A published result implies this is true for any Cauchy complete category C and κ-small category I, but we show that this is not the case in general. We prove two results that seem to cover all applications of this incorrect theorem we could find in the literature: The result holds if C has κ-small colimits and I is κ-small, or if C is an arbitrary category and I is well-founded and κ-small. In both cases, we show that the conditions are optimal in the sense that the result holds for all C if and only if I satisfies the given assumption.
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来源期刊
CiteScore
1.70
自引率
12.50%
发文量
225
审稿时长
17 days
期刊介绍: The Journal of Pure and Applied Algebra concentrates on that part of algebra likely to be of general mathematical interest: algebraic results with immediate applications, and the development of algebraic theories of sufficiently general relevance to allow for future applications.
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