On the boundary spectrum in banach algebras Page 1 BULL. AUSTRAL. MATH. SOC.
46HO5, 46H10, 47A10, 06F25 VOL. 74 (2006) [239-246] ON THE BOUNDARY SPECTRUM …

This paper illustrates some initial steps taken in the effort of unifying the theory of positivity in
ordered Banach algebas (OBAs) with the general Fredholm theory in Banach algebras. We …

Spectral theory in ordered Banach algebras | SpringerLink Skip to main content Advertisement
SpringerLink Log in Menu Find a journal Publish with us Search Cart 1.Home 2.Positivity …

Spectral theory in ordered Banach algebras (OBAs) has been investigated and several
authors have made contributions. However, the results are not applicable to non …

A classical problem posed in 1992 by Huijsmans and de Pagter asks whether, for every
positive operator T on a Banach lattice with spectrum σ (T)={1}, the inequality T≥ id holds …

We recall the definition and properties of an algebra cone in an ordered Banach algebra
(OBA) and continue to develop spectral theory for the positive elements. An element a of a …

Let $ a $ be an element of a Banach algebra $ A $. We introduce a compact subset $ T (a) $
of the complex plane, show that the function which maps $ a $ onto $ T (a) $ is upper …

Abstract top In ordered Banach algebras, we introduce eventually and asymptotically
positive elements. We give conditions for the following spectral properties: the spectral …

Harte (1982, Math. Z. 179, 431–436) initiated the study of Fredholm theory relative to a unital
homomorphism T: A→ B between unital Banach algebras A and B based on the following …

Let x be a positive element of an ordered Banach algebra. We prove a relationship between
the spectra of x and of certain positive elements y for which either xy≤ yx or yx≤ xy …