Results 61 to 70 of about 865 (99)
Boundary spectral behaviour for semiclassical operators in one dimension [PDF]
arXiv, 2004 For a class of non-selfadjoint semiclassical operators in dimension one, we get a complete asymptotic description of all eigenvalues near a critical value of the leading symbol of the operator on the boundary of the pseudospectrum.
arxiv
Bounds of numerical radius of bounded linear operator using $t$-Aluthge transform
, 2020 We develop a number of inequalities to obtain bounds for the numerical radius of a bounded linear operator defined on a complex Hilbert space using the properties of $t$-Aluthge transform.
bag, Santanu +2 more
core
Product of operators and numerical range preserving maps
, 2006 Let V be the C∗-algebra B(H) of bounded linear operators acting on the Hilbert space H, or the Jordan algebra S(H) of self-adjoint operators in B(H). For a fixed sequence (i1, . . . , im) with i1, . . . , im ∈ {1, . . . , k}, define a product of A1, . . .
Chi-Kwong Li, Nung-Sing Sze
semanticscholar +1 more source
Generalized finite operators and orthogonality
SUT Journal of Mathematics, 2011 In this paper we prove that a spectraloid operator is finite, we present some generalized finite operators and we give a new class of finite op- erators. Also, the orthogonality of some operators is studied.
S. Bouzenada
semanticscholar +1 more source
Matrices with defect index one
, 2013 In this paper, we give some characterizations of matrices which have defect index one. Recall that an n -by-n matrix A is said to be of class Sn (resp., S −1 n ) if its eigenvalues are all in the open unit disc (resp., in the complement of closed unit ...
Cheng Chang +4 more
semanticscholar +1 more source
C*-Envelopes of Jordan Operator Systems [PDF]
arXiv, 2013 We determine the boundary representations and the C*-envelope of operator systems of the form span{I,T,T*}, where T is a Jordan operator.
arxiv
, 2010 Mathematical Subject Classifications (2000): 47A10, 47A56 ...
J. Swoboda, H. K. Wimmer
semanticscholar +1 more source
Some estimates for the norm of the self-commutator [PDF]
arXiv, 2014 Different estimates for the norm of the self-commutator of a Hilbert space operator are proposed. Particularly, this norm is bounded from above by twice of the area of the numerical range of the operator. An isoperimetric-type inequality is proved.
arxiv
An intrinsic characterization of semi-normal operators [PDF]
arXiv, 2014 Two necessary and sufficient conditions for an operator to be semi-normal are revealed. For a Volterra integration operator the set where the operator and its adjoint are metrically equal is described.
arxiv
Characterization of the norm triangle equality in pre-Hilbert C✻-modules and applications
, 2009 The characterization of the norm triangle equality in pre-Hilbert C∗ -modules is given. The result is applied for describing the case of equality in some generalizations of the DunklWilliams inequality.
R. Rajić
semanticscholar +1 more source