In this paper, some additive results on Drazin inverse of a sum of Drazin invertible elements are derived. Some converse results are also presented.

Definition 3.4. The ideal group IA of a noetherian domain A is the group of invertible fractional ideals. Note that, despite the name, elements of IA need not be ideals. Every nonzero principal fractional ideal (x) is invertible (since (x)−1 = (x−1)), and a product of principal fractional ideals is principal (since (x)(y) = (xy)), as is the unit ideal (1), thus the set of nonzero principal frac...

For a row finite directed graph E, Kumjian, Pask, and Rae-burn proved that there exists a universal C *-algebra C * (E) generated by a Cuntz-Krieger E-family. In this paper we consider two density problems of invertible elements in graph C *-algebras C * (E), and it is proved that C * (E) has stable rank one, that is, the set of all invertible elements is dense in C * (E) (or in its unitization...

For a locally compact abelian group $G$, J. L. Taylor (1971) gave complete characterization of invertible elements in the measure algebra $M(G)$. Using Fourier-Stieltjes transform, this can be carried out context algebras $B(G)$. We obtain latter for $B(G)$ certain classes groups, particular, many totally minimal groups and $ax+b$-group.

In this paper, we deal with the invertible elements in a complete intuitionistic fuzzy pseudo normed algebra (in short, IFPNA) respect to Archimedean t-norm and t-conorm. It is done by studying continuity of algebraic operations IFPNA investigating condition for existence inverse an element IFPNA. Also some properties are studied. observed that set open set.

An MI-group is an algebraic structure based on a generalization of the concept of a monoid that satisfies the cancellation laws and is endowed with an invertible anti-automorphism representing inversion. In this paper, a topology is defined on an MI-group $G$ under which $G$ is  a topological MI-group. Then we will identify open, discrete and compact MI-subgroups. The connected components of th...

We study the Moore–Penrose inverse (MP-inverse) in the setting of rings with involution. The results include the relation between regular, MPinvertible and well-supported elements. We present an algebraic proof of the reverse order rule for the MP-inverse valid under certain conditions on MP-invertible elements. Applications to C∗-algebras are given. 2000 Mathematics Subject Classification: 46L...

‎In wireless communication systems‎, ‎space-time codes are applied to encode data when multiple antennas are used in the receiver and transmitter‎. ‎The concept of diversity is very crucial in designing space-time codes‎. ‎In this paper‎, ‎using the equivalent definition of full diversity space-time codes‎, ‎we first characterize all real and complex $2times 2$ rate one linear dispersion space-...