In this paper we present several new characterizations of normal and Hermitian elements in rings with involution in purely algebraic terms, and considerably simplify proofs of already existing characterizations.
Drazin–Moore–Penrose invertibility in rings
✍ Scribed by Pedro Patrı́cio; Roland Puystjens
- Publisher
- Elsevier Science
- Year
- 2004
- Tongue
- English
- Weight
- 223 KB
- Volume
- 389
- Category
- Article
- ISSN
- 0024-3795
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✦ Synopsis
Characterizations are given for elements in an arbitrary ring with involution, having a group inverse and a Moore-Penrose inverse that are equal and the difference between these elements and EP-elements is explained. The results are also generalized to elements for which a power has a Moore-Penrose inverse and a group inverse that are equal.
As an application we consider the ring of square matrices of order m over a projective free ring R with involution such that R m is a module of finite length, providing a new characterization for range-Hermitian matrices over the complexes.
📜 SIMILAR VOLUMES
Characterizations are given for existence of the Drazin inverse of a matrix over an arbitrary ring. Moreover, the Drazin inverse of a product P AQ for which there exist a P and Q such that P P A = A = AQQ can be characterized and computed. This generalizes recent results obtained for the group inver