Abstract
The primary goal of this paper is to investigate the structure of irreducible monomorphisms to and irreducible epimorphisms from finitely generated free modules over a noetherian local ring. Then we show that over such a ring, self-vanishing of Ext and Tor for a finitely generated module admitting such an irreducible homomorphism forces the ring to be regular.
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Acknowledgments
We are grateful to the referee for reading the paper very carefully and for giving many valuable suggestions that improved the presentation of the paper significantly.
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Presented by Steffen Koenig.
Takahashi was partly supported by JSPS Grants-in-Aid for Scientific Research 16K05098.
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Nasseh, S., Takahashi, R. Structure of Irreducible Homomorphisms to/from Free Modules. Algebr Represent Theor 21, 471–485 (2018). https://doi.org/10.1007/s10468-017-9722-z
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DOI: https://doi.org/10.1007/s10468-017-9722-z
Keywords
- Auslander-Reiten conjecture
- Ext-vanishing
- Injective dimension
- Irreducible homomorphism
- Projective dimension
- Regular ring
- Tor-vanishing