Abstract
A unit-picker is a map \({\mathcal {G}}\) that associates to every ring R a well-defined set \({\mathcal {G}}(R)\) of central units in R which contains \(1_R\) and is invariant under isomorphisms of rings and closed under taking inverses, and which satisfies certain set containment conditions for quotient rings, corner rings and matrix rings. Let \({\mathcal {G}}\) be a unit-picker. An element q of a ring R is \({\mathcal {G}}\)-idempotent, a special kind of the strongly regular element, if \(q^{2}=uq\) for some unit picker u of R, or equivalently, \(q=ue\), where u is a unit picker and e is an idempotent of R. In a ring R with involution \(*\), projections are self-adjoint idempotents. As a natural generalization of projections, an element q of a ring R is called a \({\mathcal {G}}\)-projection if \(q^2=uq=uq^{*}\) for some self-adjoint unit-picker u of a \(*\)-ring R, or equivalently, \(q=up\), where p is a projection. We characterize \(*\)-(strongly) regular rings in terms of the \({\mathcal {G}}\)-projection element.
Similar content being viewed by others
References
S. K. Berberian, Bear\(*\)-rings, Grundlehren der Mathematischen Wissenschafter, Vol. 95 (Springer-Verlag, New York, 1972).
G. Călugăreanu, \(UU\) rings. Carpathian Journal of Mathematics, 31(2) (2015), 157–163. https://doi.org/10.37193/CJM.2015.02.02
J. Chen and J. Cui, Two questions of L. Vaš on \(*\)-clean rings, Bull. Aust. Math. Soc., 88(3) (2013), 499–505. https://doi.org/10.1017/S0004972713000117
J. Cui and P. Danchev, Some new characterizations of periodic rings, J. Algebra Appl.,19(12) (2020), 2050235. https://doi.org/10.1142/S0219498820502357
J. Cui and P. Danchev, On strongly \(\pi \)-regular rings with involution, Commun. Math., 31(1) (2023), 73–80. https://doi.org/10.46298/cm.10273
J. Cui and Z. Wang, A note on strongly \(*\)-clean rings, J. Korean Math. Soc., 52(4) (2015), 839–851. https://doi.org/10.4134/JKMS.2015.52.4.839
J. Cui and X. Yin, Some characterizations of \(*\)-regular ring, Comm. Algebra, 45(2) (2017), 841–848. https://doi.org/10.1080/00927872.2016.1175597
J. Cui and X. Yin, On \(\pi \)-regular rings with involution, Algebra Colloq., 25(3) (2018), 509–518. https://doi.org/10.1142/S1005386718000342
J. J. Koliha and P. Patricio, Elements of rings with equal spectral idempotents, J. Aust. Math. Soc., 72(1) (2002), 137–152. https://doi.org/10.1017/S1446788700003657
M. T. Koşan, A. Leroy and J. Matczuk, On \(UJ\)-rings, Comm. Algebra, 46(5) ( 2018), 2297–2303. https://doi.org/10.1080/00927872.2017.1388814
M. T. Koşan, T. C. Quynh, T. Yıldırım and J. Žemlička, Rings such that, for each unit \(u\), \(u-u^n\) belongs to the Jacobson radical, Hacet. J. Math. Stat., 49(4) 2020, 1397–1404. https://doi.org/10.15672/hujms.542574
M. T. Koşan, T. C. Quynh, and J. Žemlička, \(UNJ\)-Rings, J. Algebra Appl., 19(9) 2020, 2050170. https://doi.org/10.1142/S0219498820501704
C. Li and Y. Zhou, On strongly \(*\)-clean rings, J. Algebra Appl., 10(6) (2011), 1363–1370. https://doi.org/10.1142/S0219498811005221
W. K. Nicholson, Strongly clean rings and Fitting’s lemma, Comm. Algebra, 27(8) (1999), 3583–3592. https://doi.org/10.1080/00927879908826649
G. Tang, H. Su and P. Yuan, Quasi-clean rings and strongly quasi-clean rings, Commun. Contemp. Math., 25(2) (2023), 2150079. https://doi.org/10.1142/S0219199721500796
G. Tang and Y. Zhou, Nil \({\cal G\it }\)-clean rings and strongly nil \({\cal G\it }\)-clean rings, J. Algebra Appl., 21(4) (2022), 2250077.https://doi.org/10.1142/S0219498822500773
L. Vaš, \(*\)-Clean rings; some clean and almost clean Baer \(*\)-rings and von Neumann algebras, J. Algebra, 324(12) (2010), 3388–3400. https://doi.org/10.1016/j.jalgebra.2010.10.011
L. Wang, Y. Qu and J. Wei, \(*\)-strongly regular rings, J. Algebra Appl., 19(11) (2020), 2050211. https://doi.org/10.1142/S0219498820502114
Y. Zhou, Generalizations of \(UU\)-rings, \(UJ\)-rings and \(UNJ\)-rings, J. Algebra Appl., 22(5) (2023), 2350102. https://doi.org/10.1142/S0219498823501025
Acknowledgements
The author is thankful to the referee for his/her valuable comments and suggestions to improve the article.
Author information
Authors and Affiliations
Corresponding author
Additional information
Communicated by B. Sury.
Rights and permissions
Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
About this article
Cite this article
Özdin, T. Characterization of \(*\)-(strongly) regular rings in terms of \({\mathcal {G}}\)-projections. Indian J Pure Appl Math (2024). https://doi.org/10.1007/s13226-024-00565-9
Received:
Accepted:
Published:
DOI: https://doi.org/10.1007/s13226-024-00565-9
Keywords
- (\({\mathcal {G}}\))-idempotent element
- (\({\mathcal {G}}\))-projection element
- \(*\)-(strongly) regular ring