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On the obscure axiom for one-sided exact categories

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 نشر من قبل Adam-Christiaan van Roosmalen
 تاريخ النشر 2020
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One-sided exact categories are obtained via a weakening of a Quillen exact category. Such one-sided exact categories are homologically similar to Quillen exact categories: a one-sided exact category $mathcal{E}$ can be (essentially uniquely) embedded into its exact hull ${mathcal{E}}^{textrm{ex}}$; this embedding induces a derived equivalence $textbf{D}^b(mathcal{E}) to textbf{D}^b({mathcal{E}}^{textrm{ex}})$. Whereas it is well known that Quillens obscure axioms are redundant for exact categories, some one-sided exact categories are known to not satisfy the corresponding obscure axiom. In fact, we show that the failure of the obscure axiom is controlled by the embedding of $mathcal{E}$ into its exact hull ${mathcal{E}}^{textrm{ex}}.$ In this paper, we introduce thr



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