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arXiv · 0805.4483

Postnikov towers, k-invariants and obstruction theory for DG categories

Goncalo Tabuada
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Abstract

By inspiring ourselves in Drinfeld's DG quotient, we develop Postnikov towers, k-invariants and an obstruction theory for dg categories. As an application, we obtain the following `rigidification' theorem: let A be a homologically connective dg category and F:B -> H0(A) a dg functor to its homotopy category. If the family of obstruction classes vanishes, then a lift for F exists.

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Goncalo Tabuada. 2008-05-29. Postnikov towers, k-invariants and obstruction theory for DG categories. https://arxiv.org/abs/0805.4483

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