Abstract
Locally projective (i.e., flat Mittag-Leffler) modules are known to provide for approximations only over perfect rings. Recently, very flat modules were introduced by Positselski in his study of contraherent cosheaves on a scheme X. For \(X=\hbox {Spec}(R)\), where R is a Noetherian domain, we show that locally very flat modules provide for approximations only if X is finite.
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Acknowledgements
This research has been supported by GAČR 14-15479S.
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Trlifaj, J. (2016). Classes of Flat Modules Arising in Algebraic Geometry and Approximations. In: Herbera, D., Pitsch, W., Zarzuela, S. (eds) Extended Abstracts Spring 2015. Trends in Mathematics(), vol 5. Birkhäuser, Cham. https://doi.org/10.1007/978-3-319-45441-2_29
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DOI: https://doi.org/10.1007/978-3-319-45441-2_29
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