Research Article
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Core-EP decomposition and related relations revisited

Year 2026, Issue: Advanced Online Publication, 1 - 23, 18.02.2026
https://izlik.org/JA38ZN28EB

Abstract

We study relations that are induced by the core-EP decomposition. We revisit the core-EP preorder and extend the concepts of the core-minus, the c-minus, and the c-star partial orders from the set of all $n\times n$ complex matrices to the set of all core-EP invertible elements in a $\ast$-ring. Several characterizations of these relations are presented and thus some known results are generalized.

References

  • O. M. Baksalary and G. Trenkler, Core inverse of matrices, Linear Multilinear Algebra, 58(6) (2010), 681-697.
  • D. S. Djordjevic, D. S. Rakic and J. Marovt, Minus partial order in Rickart rings, Publ. Math. Debrecen, 87(3/4) (2015), 291-305.
  • G. Dolinar, B. Kuzma and J. Marovt, A note on partial orders of Hartwig, Mitsch, and Semrl, Appl. Math. Comput., 270 (2015), 711-713.
  • G. Dolinar, B. Kuzma, J. Marovt and B. Ungor, Properties of core-EP order in rings with involution, Front. Math. China, 14(4) (2019), 715-736.
  • G. Dolinar, J. Marovt and D. Mosic, On EP-nilpotent decomposition in $\ast$-rings, Publ. Math. Debrecen, 100(3/4) (2022), 405-426.
  • M. P. Drazin, Natural structures on semigroups with involution, Bull. Amer. Math. Soc., 84(1) (1978), 139-141.
  • Y. Gao and J. Chen, Pseudo core inverses in rings with involution, Comm. Algebra, 46(1) (2018), 38-50.
  • Y. Gao, J. Chen and Y. Ke, *-DMP elements in $\ast $-semigroups and $\ast$-rings, Filomat, 32 (2018), 3073-3085.
  • R. E. Hartwig, How to partially order regular elements,Math. Japon., 25 (1980), 1-13.
  • R. E. Hartwig and J. Luh, A note on the group structure on unit regular ring elements, Pacific J. Math., 71 (1977), 449-461.
  • A. Herrero and N. Thome, Sharp partial order and linear autonomous systems, Appl. Math. Comput., 366 (2020), 124736 (11 pp).
  • P. M. Higgins, Techniques of Semigroup Theory, Oxford University Press, New York, 1992.
  • Q. Ling, X. Hua, H. Wang and S. Liu, The C-N-star, s-star and c-minus partial orders, J. Math. Inequal., 19(1) (2025), 177-194.
  • K. Manjunatha Prasad and K. S. Mohana, Core-EP inverse, Linear Multilinear Algebra, 62(6) (2014), 792-802.
  • J. Marovt, On partial orders in Rickart rings, Linear Multilinear Algebra, 63(9) (2015), 1707-1723.
  • J. Marovt, On star, sharp, core, and minus partial orders in Rickart rings, Banach J. Math. Anal., 10(3) (2016), 495-508.
  • J. Marovt and D. Mosic, On some orders in $\ast $-rings based on the core-EP decomposition, J. Algebra Appl., 21(1) (2022), 2250010 (24 pp).
  • S. K. Mitra, P. Bhimasankaram and S. B. Malik, Matrix Partial Orders, Shorted Operators and Applications, World Scientific, Hackensack, 2010.
  • H. Mitsch, A natural partial order for semigroups, Proc. Amer. Math. Soc., 97(3) (1986), 384-388.
  • D. Mosic, Weighted core-EP inverse and weighted core-EP pre-orders in a $C^{\ast}$-algebra, J. Aust. Math. Soc., 111(1) (2021), 76-110.
  • K. S. S. Nambooripad, The natural partial order on a regular semigroup, Proc. Edinburgh Math. Soc., 23 (1980), 249-260.
  • D. S. Rakic and D. S. Djordjevic, Star, sharp, core and dual core partial order in rings with involution, Appl. Math. Comput., 259 (2015), 800-818.
  • C. R. Rao and S. K. Mitra, Generalized Inverse of Matrices and Its Applications, Wiley, New York, 1971.
  • P. Semrl, Automorphism of $\mathcal{B}(H)$ with respect to minus partial order, J. Math. Anal. Appl., 369 (2010), 205-213.
  • S. Xu, J. Chen and X. Zhang, New characterizations for core inverses in rings with involution, Front. Math. China, 12(1) (2017), 231-246.
  • H. Wang, Core-EP decomposition and its applications, Linear Algebra Appl., 508 (2016), 289-300.
  • D. Zhang, L. Ma and D. Mosic, Representations of the Moore-Penrose inverse of a $2\times 2$ block matrix based on Schur complements, Appl. Math. Comput., 512 (2026), 129776 (10 pp).
  • D. Zhang, Y. Zhao and D. Mosic, The generalized Drazin inverse of the sum of two elements in a Banach algebra, J. Comput. Appl. Math., 470 (2025), 116701 (12 pp).

Year 2026, Issue: Advanced Online Publication, 1 - 23, 18.02.2026
https://izlik.org/JA38ZN28EB

Abstract

References

  • O. M. Baksalary and G. Trenkler, Core inverse of matrices, Linear Multilinear Algebra, 58(6) (2010), 681-697.
  • D. S. Djordjevic, D. S. Rakic and J. Marovt, Minus partial order in Rickart rings, Publ. Math. Debrecen, 87(3/4) (2015), 291-305.
  • G. Dolinar, B. Kuzma and J. Marovt, A note on partial orders of Hartwig, Mitsch, and Semrl, Appl. Math. Comput., 270 (2015), 711-713.
  • G. Dolinar, B. Kuzma, J. Marovt and B. Ungor, Properties of core-EP order in rings with involution, Front. Math. China, 14(4) (2019), 715-736.
  • G. Dolinar, J. Marovt and D. Mosic, On EP-nilpotent decomposition in $\ast$-rings, Publ. Math. Debrecen, 100(3/4) (2022), 405-426.
  • M. P. Drazin, Natural structures on semigroups with involution, Bull. Amer. Math. Soc., 84(1) (1978), 139-141.
  • Y. Gao and J. Chen, Pseudo core inverses in rings with involution, Comm. Algebra, 46(1) (2018), 38-50.
  • Y. Gao, J. Chen and Y. Ke, *-DMP elements in $\ast $-semigroups and $\ast$-rings, Filomat, 32 (2018), 3073-3085.
  • R. E. Hartwig, How to partially order regular elements,Math. Japon., 25 (1980), 1-13.
  • R. E. Hartwig and J. Luh, A note on the group structure on unit regular ring elements, Pacific J. Math., 71 (1977), 449-461.
  • A. Herrero and N. Thome, Sharp partial order and linear autonomous systems, Appl. Math. Comput., 366 (2020), 124736 (11 pp).
  • P. M. Higgins, Techniques of Semigroup Theory, Oxford University Press, New York, 1992.
  • Q. Ling, X. Hua, H. Wang and S. Liu, The C-N-star, s-star and c-minus partial orders, J. Math. Inequal., 19(1) (2025), 177-194.
  • K. Manjunatha Prasad and K. S. Mohana, Core-EP inverse, Linear Multilinear Algebra, 62(6) (2014), 792-802.
  • J. Marovt, On partial orders in Rickart rings, Linear Multilinear Algebra, 63(9) (2015), 1707-1723.
  • J. Marovt, On star, sharp, core, and minus partial orders in Rickart rings, Banach J. Math. Anal., 10(3) (2016), 495-508.
  • J. Marovt and D. Mosic, On some orders in $\ast $-rings based on the core-EP decomposition, J. Algebra Appl., 21(1) (2022), 2250010 (24 pp).
  • S. K. Mitra, P. Bhimasankaram and S. B. Malik, Matrix Partial Orders, Shorted Operators and Applications, World Scientific, Hackensack, 2010.
  • H. Mitsch, A natural partial order for semigroups, Proc. Amer. Math. Soc., 97(3) (1986), 384-388.
  • D. Mosic, Weighted core-EP inverse and weighted core-EP pre-orders in a $C^{\ast}$-algebra, J. Aust. Math. Soc., 111(1) (2021), 76-110.
  • K. S. S. Nambooripad, The natural partial order on a regular semigroup, Proc. Edinburgh Math. Soc., 23 (1980), 249-260.
  • D. S. Rakic and D. S. Djordjevic, Star, sharp, core and dual core partial order in rings with involution, Appl. Math. Comput., 259 (2015), 800-818.
  • C. R. Rao and S. K. Mitra, Generalized Inverse of Matrices and Its Applications, Wiley, New York, 1971.
  • P. Semrl, Automorphism of $\mathcal{B}(H)$ with respect to minus partial order, J. Math. Anal. Appl., 369 (2010), 205-213.
  • S. Xu, J. Chen and X. Zhang, New characterizations for core inverses in rings with involution, Front. Math. China, 12(1) (2017), 231-246.
  • H. Wang, Core-EP decomposition and its applications, Linear Algebra Appl., 508 (2016), 289-300.
  • D. Zhang, L. Ma and D. Mosic, Representations of the Moore-Penrose inverse of a $2\times 2$ block matrix based on Schur complements, Appl. Math. Comput., 512 (2026), 129776 (10 pp).
  • D. Zhang, Y. Zhao and D. Mosic, The generalized Drazin inverse of the sum of two elements in a Banach algebra, J. Comput. Appl. Math., 470 (2025), 116701 (12 pp).
There are 28 citations in total.

Details

Primary Language English
Subjects Algebra and Number Theory
Journal Section Research Article
Authors

Gregor Dolinar

Janko Marovt

Dijana Mosic

Submission Date September 8, 2025
Acceptance Date January 11, 2026
Early Pub Date February 18, 2026
Publication Date February 18, 2026
DOI https://doi.org/10.24330/ieja.1892320
IZ https://izlik.org/JA38ZN28EB
Published in Issue Year 2026 Issue: Advanced Online Publication

Cite

APA Dolinar, G., Marovt, J., & Mosic, D. (2026). Core-EP decomposition and related relations revisited. International Electronic Journal of Algebra, Advanced Online Publication, 1-23. https://doi.org/10.24330/ieja.1892320
AMA 1.Dolinar G, Marovt J, Mosic D. Core-EP decomposition and related relations revisited. IEJA. 2026;(Advanced Online Publication):1-23. doi:10.24330/ieja.1892320
Chicago Dolinar, Gregor, Janko Marovt, and Dijana Mosic. 2026. “Core-EP Decomposition and Related Relations Revisited”. International Electronic Journal of Algebra, no. Advanced Online Publication: 1-23. https://doi.org/10.24330/ieja.1892320.
EndNote Dolinar G, Marovt J, Mosic D (February 1, 2026) Core-EP decomposition and related relations revisited. International Electronic Journal of Algebra Advanced Online Publication 1–23.
IEEE [1]G. Dolinar, J. Marovt, and D. Mosic, “Core-EP decomposition and related relations revisited”, IEJA, no. Advanced Online Publication, pp. 1–23, Feb. 2026, doi: 10.24330/ieja.1892320.
ISNAD Dolinar, Gregor - Marovt, Janko - Mosic, Dijana. “Core-EP Decomposition and Related Relations Revisited”. International Electronic Journal of Algebra. Advanced Online Publication (February 1, 2026): 1-23. https://doi.org/10.24330/ieja.1892320.
JAMA 1.Dolinar G, Marovt J, Mosic D. Core-EP decomposition and related relations revisited. IEJA. 2026;:1–23.
MLA Dolinar, Gregor, et al. “Core-EP Decomposition and Related Relations Revisited”. International Electronic Journal of Algebra, no. Advanced Online Publication, Feb. 2026, pp. 1-23, doi:10.24330/ieja.1892320.
Vancouver 1.Gregor Dolinar, Janko Marovt, Dijana Mosic. Core-EP decomposition and related relations revisited. IEJA. 2026 Feb. 1;(Advanced Online Publication):1-23. doi:10.24330/ieja.1892320

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