scholarly journals Enclosure of the numerical range and resolvent estimates of non-selfadjoint operator functions

2020 ◽  
Vol 10 (2) ◽  
pp. 379-413
Author(s):  
Axel Torshage
Keyword(s):  
Selfadjoint Operator ◽  
Numerical Range ◽  
Resolvent Estimates ◽  
Operator Functions

scholarly journals On Basis Properties of Selfadjoint Operator Functions

2000 ◽  
Vol 178 (2) ◽  
pp. 306-342 ◽  
Author(s):  
T.Ya. Azizov ◽  
A. Dijksma ◽  
L.I. Sukhocheva
Keyword(s):  
Selfadjoint Operator ◽  
Operator Functions

scholarly journals The block numerical range of analytic operator functions

2014 ◽  
pp. 901-934
Author(s):  
Agnes Radl ◽  
Christiane Tretter ◽  
Markus Wagenhofer
Keyword(s):  
Numerical Range ◽  
Analytic Operator ◽  
Operator Functions

scholarly journals Enclosure of the Numerical Range of a Class of Non-selfadjoint Rational Operator Functions

2017 ◽  
Vol 88 (2) ◽  
pp. 151-184 ◽  
Author(s):  
Christian Engström ◽  
Axel Torshage
Keyword(s):  
Numerical Range ◽  
Operator Functions

A new method for approximation of closed convex subsets of B(H)

Filomat ◽  
2017 ◽  
Vol 31 (19) ◽  
pp. 6005-6013
Author(s):  
Mahdi Iranmanesh ◽  
Fatemeh Soleimany
Keyword(s):  
Best Approximation ◽  
Numerical Range ◽  
New Method ◽  
C Algebra ◽  
Convex Subsets

In this paper we use the concept of numerical range to characterize best approximation points in closed convex subsets of B(H): Finally by using this method we give also a useful characterization of best approximation in closed convex subsets of a C*-algebra A.

scholarly journals Quantum Orlicz Spaces in Information Geometry

2004 ◽  
Vol 11 (04) ◽  
pp. 359-375 ◽  
Author(s):  
R. F. Streater
Keyword(s):  
Quantum Information ◽  
Tangent Space ◽  
Selfadjoint Operator ◽  
Affine Connection ◽  
Orlicz Spaces ◽  
Trace Class ◽  
Information Geometry ◽  
Young Function ◽  
Affine Structure ◽  
Cotangent Space

Let H0 be a selfadjoint operator such that Tr e−βH0 is of trace class for some β < 1, and let χɛ denote the set of ɛ-bounded forms, i.e., ∥(H0+C)−1/2−ɛX(H0+C)−1/2+ɛ∥ < C for some C > 0. Let χ := Span ∪ɛ∈(0,1/2]χɛ. Let [Formula: see text] denote the underlying set of the quantum information manifold of states of the form ρx = e−H0−X−ψx, X ∈ χ. We show that if Tr e−H0 = 1. 1. the map Φ, [Formula: see text] is a quantum Young function defined on χ 2. The Orlicz space defined by Φ is the tangent space of [Formula: see text] at ρ0; its affine structure is defined by the (+1)-connection of Amari 3. The subset of a ‘hood of ρ0, consisting of p-nearby states (those [Formula: see text] obeying C−1ρ1+p ≤ σ ≤ Cρ1 − p for some C > 1) admits a flat affine connection known as the (−1) connection, and the span of this set is part of the cotangent space of [Formula: see text] 4. These dual structures extend to the completions in the Luxemburg norms.

Continuity of submatrices and Ritz sets associated to a point in the numerical range

2021 ◽  
Vol 624 ◽  
pp. 1-13
Author(s):  
Kennett L. Dela Rosa ◽  
Hugo J. Woerdeman
Keyword(s):  
Numerical Range

a-Numerical range on $$C^*$$-algebras

Positivity ◽  
2021 ◽  
Author(s):  
Abdellatif Bourhim ◽  
Mohamed Mabrouk
Keyword(s):  
Numerical Range ◽  
C Algebras

On the maximal numerical range of the bimultiplication M2,A,B

2021 ◽  
pp. 1-8
Author(s):  
Abderrahim Baghdad ◽  
Chraibi Kaadoud Mohamed
Keyword(s):  
Numerical Range
Sign in / Sign up

Export Citation Format

Share Document