## All $n$-cotilting modules are pure-injective

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- by Jan Šťovíček PDF
- Proc. Amer. Math. Soc.
**134**(2006), 1891-1897 Request permission

## Abstract:

We prove that all $n$-cotilting $R$-modules are pure-injective for any ring $R$ and any $n \ge 0$. To achieve this, we prove that ${^{\perp _1} U}$ is a covering class whenever $U$ is an $R$-module such that ${^{\perp _1} U}$ is closed under products and pure submodules.## References

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## Additional Information

**Jan Šťovíček**- Affiliation: Faculty of Mathematics and Physics, Department of Algebra, Charles University, Sokolovská 83, 186 75 Prague 8, Czech Republic
- Address at time of publication: Institutt for Matematiske FAG, Norwegian University of Science and Technology, N-7491 Trondheim, Norway
- Email: stovicek@karlin.mff.cuni.cz, stovicek@math.ntnu.no
- Received by editor(s): February 22, 2005
- Published electronically: January 17, 2006
- Additional Notes: This research was supported by a grant of the Industrie Club Duesseldorf and by GAČR 201/05/H005.
- Communicated by: Martin Lorenz
- © Copyright 2006
American Mathematical Society

The copyright for this article reverts to public domain 28 years after publication. - Journal: Proc. Amer. Math. Soc.
**134**(2006), 1891-1897 - MSC (2000): Primary 16D90; Secondary 16E30, 03E75
- DOI: https://doi.org/10.1090/S0002-9939-06-08256-6
- MathSciNet review: 2215116