A note on maximal numerical range

Author(s):

Abderrahim Baghdad* , Mohamed Chraibi Kaadoud

Message:
Article Type:
Research/Original Article (دارای رتبه معتبر)
Abstract:

We shed some light on the Pythagorean relation for operator established in [7] and we study its relationship with the maximal numerical range. We then get some informations of maximal numerical ranges of selfadjoint operators. This allows us to show, contrary to the closure of the numerical range, the non-continuity in the sens of Hausdorff of the maximal numerical range. AMS Subject Classification: 47A12; 47A30; 47A63; 47B15; 47B47 Keywords and Phrases: Spectrum, numerical range, maximal numerical range.

Keywords:

Spectrum , point spectrum , numerical range , normaloid operators , compact operator

Language:
English
Published:
Journal of Mathematical Extension, Volume:14 Issue: 1, Winter 2020
Pages:
117 to 126
https://www.magiran.com/p2262763