Abstract
Let T be a Wakamatsu tilting module. A module M is called (n, T)-copure injective (resp. (n, T)-copure flat) if ɛ 1 T (N, M) = 0 (resp. Γ T1 (N, M) = 0) for any module N with T-injective dimension at most n (see Definition 2.2). In this paper, it is shown that M is (n, T)-copure injective if and only if M is the kernel of an I n (T)-precover f: A → B with A ∈ Prod T. Also, some results on Prod T-syzygies are presented. For instance, it is shown that every nth Prod T-syzygy of every module, generated by T, is (n, T)-copure injective.
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References
Angleri-Hugel, L. and Coelho, F. U., Infinitely generated tilting modules of finite projective dimension, Forum Math., 13, 2001, 239–250.
Bazzoni, S., A characterization of n-cotilting and n-tilting modules, J. Algebra, 273, 2005, 359–372.
Enochs, E. E. and Jenda, O. M. G., Relative Homological Algebra, Walter de Gruyter, Berlin, New York, 2000.
Green, E. L., Reiten, I. and Solberg, O., Dualities on Generalized Koszul Algebras, Mem. Amer. Math. Soc., 159, A. M. S., Providence, RI, 2002, 754.
Nikmehr, M. J., Shaveisi, F. and Nikandish, R., n-Projective modules, Algebras Groups Geom., 24, 2007, 447–454.
Nikmehr, M. J. and Shaveisi, F., T-Dimension and (n + 1/2, T)-projective modules, Southeast Asian Bull. Math., 35, 2011, 1–11.
Rotman, J. J., An Introduction to Homological Algebra, Academic Press, New York, 1979.
Wakamatsu, T., On modules with trivial self-extension, J. Algebra, 114, 1998, 106–114.
Wei, J., n-Star modules and n-tilting modules, J. Algebra, 283, 2005, 711–722.
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Nikmehr, M.J., Shaveisi, F. Relative T-injective modules and relative T-flat modules. Chin. Ann. Math. Ser. B 32, 497–506 (2011). https://doi.org/10.1007/s11401-011-0662-3
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DOI: https://doi.org/10.1007/s11401-011-0662-3
Keywords
- Wakamatsu tilting module
- (n, T)-Copure injective module
- (n, T)-Copure flat module
- T-Projective dimension
- T-Injective dimension