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Morita Equivalence and Morita Duality for Rings with Local Units and the Subcategory of Projective Unitary Modules

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Abstract

We study Morita equivalence and Morita duality for rings with local units. We extend Auslander’s results on the theory of Morita equivalence and the Azumaya–Morita duality theorem to rings with local units. As a consequence, we give a version of Morita theorem and Azumaya–Morita duality theorem over rings with local units in terms of their full subcategory of finitely generated projective unitary modules and full subcategory of finitely generated injective unitary modules.

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References

  1. Abrams, G.D.: Morita equivalence for rings with local units. Commun. Algebra 11, 801–837 (1983)

    Article  MathSciNet  Google Scholar 

  2. Abrams, G.D., Ara, P., Molina, M.S.: Leavitt Path Algebras, Lecture Notes in Mathematics 2191, p. 287. Springer, London (2017)

    Google Scholar 

  3. Anderson, F.W., Fuller, K.R.: Rings and Categories of Modules, Graduate Texts in Mathematics, vol. 13, 2nd edn. Springer, New York (1992)

    Book  Google Scholar 

  4. Ánh, P.N., Márki, L.: Morita equivalence for rings without identity. Tsukuba J. Math. 11(2), 1–16 (1987)

    MathSciNet  Google Scholar 

  5. Ánh, P.N., Menini, C.: Morita duality for rings with local units. J. Algebra 164(3), 632–641 (1994)

    Article  MathSciNet  Google Scholar 

  6. Auslander, M.: Representation theory of Artin algebras I. Commun. Algebra 1, 177–268 (1974)

    Article  MathSciNet  Google Scholar 

  7. Auslander, M.: Representation theory of Artin algebras II. Commun. Algebra 1, 269–310 (1974)

    Article  MathSciNet  Google Scholar 

  8. Bautista, R., Liu, S., Paquette, C.: Representation theory of strongly locally finite quivers. Proc. Lond. Math. Soc. (3) 106(1), 97–162 (2013)

    Article  MathSciNet  Google Scholar 

  9. Crawley-Boevey, W.: Locally finitely presented additive categories. Commun. Algebra 22(5), 1641–1674 (1994)

    Article  MathSciNet  Google Scholar 

  10. Dlab, V., Ringel, C.M.: The Module Theoretical Approach to Quasi-hereditary Algebras. London Mathematical Society Lecture Note Series, vol. 168, pp. 200–224. Cambridge University Press, Cambridge (1992)

    Google Scholar 

  11. Drozd, Y., Mazorchuk, V.: Representation type of \(_{\lambda }^{\infty } H_{\mu }^1\). Q. J. Math. 57(3), 319–338 (2006)

    Article  MathSciNet  Google Scholar 

  12. Fazelpour, Z., Nasr-Isfahani, A.: Auslander correspondence for Kawada rings. arXiv:2105.10898

  13. Fazelpour, Z., Nasr-Isfahani, A.: Finiteness and purity of subcategories of the module categories. arXiv:2203.03294

  14. Fazelpour, Z., Nasr-Isfahani, A.: Locally finitely presented Grothendieck categories and the pure semisimplicity conjecture. arXiv:2401.07008

  15. Fuller, K.R.: On rings whose left modules are direct sums of finitely generated modules. Proc. Am. Math. Soc. 54, 39–44 (1976)

    Article  MathSciNet  Google Scholar 

  16. Fuller, K.R., Hullinger, H.: Rings with finiteness conditions and their categories of functors. J. Algebra 55, 94–105 (1978)

    Article  MathSciNet  Google Scholar 

  17. Gabriel, P.: Des catégories abéliennes. Bull. Soc. Math. Fr. 90, 323–448 (1962)

    Article  Google Scholar 

  18. Garcia, J.L.: Idempotent rings which are equivalent to rings with identity. Tsukuba J. Math. 17(1), 71–76 (1993)

    Article  MathSciNet  Google Scholar 

  19. Harada, M.: Perfect categories IV. Quasi-Frobenius categories. Osaka J. Math. 10, 585–596 (1973)

    MathSciNet  Google Scholar 

  20. Hungerford, T.W.: Algebra. Graduate Texts in Mathematics, vol. 73. Springer, Cham (1974)

    Google Scholar 

  21. Lundström, P.: Separable groupoid rings. Commun. Algebra 34(8), 3029–3041 (2006)

    Article  MathSciNet  Google Scholar 

  22. Menini, C.: Gabriel–Popescu type theorems and graded modules. In: van Oystaeyen, F., Le, L. (eds.) Perspectives in Ring Theory, pp. 239–251. Kluwer Academic Publishers, Bruyn (1988)

    Chapter  Google Scholar 

  23. Meyer, R.: Morita equivalence in algebra and geometry. CiteSeerX 10.1.1.35.3449

  24. Morita, K.: Duality of modules and its applications to the theory of rings with minimum condition. Sci. Rep. Tokyo Kyoiku Daigaku Sect. A 6, 83–142 (1958)

    MathSciNet  Google Scholar 

  25. Nystedt, P.: A survey of s-unital and locally unital rings. Rev. Integr. 37(2), 251–260 (2019)

    MathSciNet  Google Scholar 

  26. Simson, D.: On pure global dimension of locally finitely presented Grothendieck categories. Fundam. Math. 96, 91–116 (1977)

    Article  MathSciNet  Google Scholar 

  27. Simson, D.: On pure semi-simple Grothendieck categories I. Fundam. Math. 100, 211–222 (1978)

    Article  MathSciNet  Google Scholar 

  28. Simson, D.: On pure semi-simple Grothendieck categories II. Fundam. Math. 110, 107–116 (1980)

    Article  Google Scholar 

  29. Stenström, B.: Rings of quotients. In: An Introduction to Methods of Ring Theory, in: Die Grundlehren der Mathematischen Wissenschaften, vol. 217. Springer, New York (1975)

  30. Vercruysse, J.: Local units versus local projectivity dualisations: corings with local structure maps. Commun. Algebra 34(6), 2079–2103 (2006)

    Article  MathSciNet  Google Scholar 

  31. Wisbauer, R.: Foundations of module and ring theory. In: A Handbook for Study and Research. Revised and Translated from the 1988 German edition. Algebra, Logic and Applications, 3. Gordon and 3. Gordon and Breach Science Publishers, Philadelphia, PA (1991)

  32. Wisbauer, R.: Zur Brauer-Thrall-Vermutung für Ringe. Arch. Math. 44, 138–146 (1985)

    Article  MathSciNet  Google Scholar 

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Acknowledgements

The authors would like to thank the referee for a careful reading of this paper and making helpful suggestions and comments that improved the paper.

Funding

The research of the first author was in part supported by a grant from IPM. Also, the research of the second author was in part supported by a grant from IPM (No. 14020416). The work of the second author is based upon research funded by Iran National Science Foundation (INSF) under Project No. 4001480.

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The authors of this paper, ZF and AN-I, have contributed equally to the work and preparation of the manuscript.

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Correspondence to Alireza Nasr-Isfahani.

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Communicated by Lidia Angeleri Hügel.

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Fazelpour, Z., Nasr-Isfahani, A. Morita Equivalence and Morita Duality for Rings with Local Units and the Subcategory of Projective Unitary Modules. Appl Categor Struct 32, 10 (2024). https://doi.org/10.1007/s10485-024-09764-1

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