Regular and T-fredholm Elements in Banach Algebras


Dragan Đorđević


Let $T:A\to B$ be an algebra homomorphism of a Banach algebra $A$ to an algebra $B$. An element $a\in A$ is $T$--Fredholm [2] if $T(A)\in B^{-1}$ and $a\in A$ is regular [3] provided there is an element $a'\in A$ such that $a=aa'a$. We investigate regular and $T$-Fredholm elements in Banach algebras. As a corollary, we get a well known result [5, Theorem 3].