Quasi-Jordan Banach Algebras

Journal Article

Jam, Reem K. Alhefthi, Akhlaq A. Siddiqui, and Fatmah B. . 2014

• نوع عمل المنشور: بحث علمي أصيل
• رابط المنشور على الويب: http://dx.doi.org/10.1155/2014/690806
• المجلة \ الصحيفة: Abstract and Applied Analysis
• رقم العدد: 2014
• رقم الإصدار السنوي: 2014
• الصفحات: from 1 to 11

مستخلص المنشور

We initiate a study of quasi-Jordan normed algebras. It is demonstrated that any quasi-Jordan Banach algebra with a norm 1 unit can be given an equivalent norm making the algebra isometrically isomorphic to a closed right ideal of a unital split quasi-Jordan Banach algebra; the set of invertible elements may not be open; the spectrum of any element is nonempty, but it may be neither bounded nor closed and hence not compact. Some characterizations of the unbounded spectrum of an element in a split quasi-Jordan Banach algebra with certain examples are given in the end.