Please use this identifier to cite or link to this item:
Title: Essential g-ascent and g-descent of a closed linear relation in Hilbert spaces
Authors: Garbouj, Zied
Skhiri, Haïkel
Keywords: Range subspace;Closed linear relation;Spectrum;Ascent;Essential ascent;Descent;Essential descent;Semi-Fredholm relation;Rango de subespacio;Relación lineal cerrada;Espectro;Ascenso;Ascenso esencial;Descenso;Descenso esencial;Relación semi-Fredholm
Issue Date: 2017
Publisher: Universidad de Extremadura
Abstract: We define and discuss for a closed linear relation in a Hilbert space the notions of essential g-ascent (resp. g-descent) and g-ascent (resp. g-descent) spectrums. We improve in the Hilbert space case some results given by E. Chafai in a Banach space [Acta Mathematica Sinica, 34 B, 1212-1224, 2014] and several results related to the ascent (resp. essential ascent) spectrum for a bounded linear operator on a Banach space [Studia Math, 187, 59-73, 2008] are extended to closed linear relations on Hilbert spaces. We prove also a decomposition theorem for closed linear relations with finite essential g-ascent or g-descent.
Appears in Collections:Extracta Mathematicae Vol. 32, nº 2 (2017)

Files in This Item:
File Description SizeFormat 
2605-5686_32_2_125.pdf205,68 kBAdobe PDFView/Open

This item is licensed under a Creative Commons License Creative Commons