Naslov
Roberts orthogonality and the Davis–Wielandt shell

Autori
Berić, Tomislav

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, kratko priopćenje, znanstveni

Skup
Advanced Course in Operator Theory and Complex Analysis

Mjesto i datum
Bologna, Italija, 11.06.2018. - 14.06.2018

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Nije recenziran

Ključne riječi
Birkhoff-James orthogonality, numerical range, Davis-Wielandt shell

Sažetak
Let $\mathcal{; ; A}; ; $ be a $C^*$--algebra with the unit $e$. We say that $x, y \in \mathcal{; ; A}; ; $ are Roberts orthogonal if $$ \|x + \lambda y\| = \|x - \lambda y\|, \quad \lambda \in \mathbb{; ; C}; ; . $$ We give a characterization of Roberts orthogonality of $a$ and $e$ in terms of the Davis--Wielandt shell and show that for some classes of elements, orthogonality of $a$ and $e$ can be ascertained via the numerical range of $a$. This is a joint work with Ljiljana Arambašić and Rajna Rajić.

Izvorni jezik
Engleski

Znanstvena područja
Matematika

POVEZANOST RADA