Results 31 to 40 of about 481,322 (128)

Exact and Approximate Operator Parallelism [PDF]

Canadian Mathematical Bulletin, 2015
Abstract Extending the notion of parallelism we introduce the concept of approximate parallelism in normed spaces and then substantially restrict ourselves to the setting of Hilbert space operators endowed with the operator norm. We present several characterizations of the exact and approximate operator parallelism in the algebra B(ℋ)
Moslehian, Mohammad Sal, Zamani, Ali
openaire   +2 more sources

A NOTE ON BADLY APPROXIMABLE LINEAR FORMS

, 2011
In this paper we investigate the analogue of the classical badly approximable setup in which the distance to the nearest integer ‖⋅‖ is replaced by the sup norm |⋅|.
MUMTAZ HUSSAIN
core   +1 more source

Self-induced compactness in Banach spaces [PDF]

, 2017
We consider the question: is every compact set in a Banach space X contained in the closed unit range of a compact (or even approximable) operator on X? We give large classes of spaces where the question has an affirmative answer, but observe that it has
Jarchow, H., Casazza, P. G.
core  

Diophantine approximation and badly approximable sets

, 2006
Let (X,d) be a metric space and (Ω,d) a compact subspace of X which supports a non-atomic finite measure m. We consider ‘natural’ classes of badly approximable subsets of Ω.
Kristensen, S., Simon Kristensen, Rebecca Thorn, Velani, S., Thorn, R., Sanju Velani   +5 more
core   +1 more source

Comment on "Regression with slowly varying regressors and nonlinear trends" by P.C.B. Phillips [PDF]

Standardized slowly varying regressors are shown to be $L_p$-approximable. This fact allows one to relax the assumption on linear processes imposed in central limit results by P.C.B.
Mynbaev, Kairat
core  

Asymptotic properties of OLS estimates in autoregressions with bounded or slowly growing deterministic trends [PDF]

We propose a general method of modeling deterministic trends for autoregressions. The method relies on the notion of $L_2$-approximable regressors previously developed by the author.
Mynbaev, Kairat
core  

Global Solvability and Simultaneously Approximable Vectors

, 2002
We consider a class of sum of squares operators on a torus and we prove that global solvability is equivalent to an algebraic condition involving simultaneously approximable ...
Petronilho, Gerson
core   +1 more source

Approximation spaces for H-operators

Involve, a Journal of Mathematics
This paper defines and establishes relations among approximation spaces of certain operators called \textit{H-operators}, which generalize the notion of self-adjoint to Banach spaces.
Aksoy, Asuman Güven, Thiong, Daniel Akech   +1 more
openaire   +2 more sources

Regular Galerkin approximation of holomorphic T-Garding operator eigenvalue problems

, 2016
In this paper we deal with holomorphic Fredholm operator eigen-value problems and their approximations by Galerkin schemes. We consider operator functions, which don´t have the structure "coercive+compact". In this case the regularity (in sense
Halla, Martin
core   +2 more sources

$\Cal P$-approximable compact spaces

, 1991
summary:For every topological property $\Cal P$, we define the class of $\Cal P$-approximable spaces which consists of spaces X having a countable closed cover $\gamma $ such that the ``section'' $X(x,\gamma )= \bigcap \{F\in \gamma :x\in F\}$ has the ...
Tkačenko, Michael G.
core   +1 more source