Abstract
We provide a criterion for the existence of right approximations in cocomplete additive categories; it is a straightforward generalisation of a result due to El Bashir. This criterion is used to construct adjoint functors in homotopy categories. Applications include the study of (pure) derived categories. For instance, it is shown that the pure derived category of any module category is compactly generated.
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This research was partially supported by DFG Schwerpunktprogramm 1388.
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Krause, H. Approximations and adjoints in homotopy categories. Math. Ann. 353, 765–781 (2012). https://doi.org/10.1007/s00208-011-0703-y
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DOI: https://doi.org/10.1007/s00208-011-0703-y