• Corpus ID: 119616343

On Approximation Schemes and Compactness

  title={On Approximation Schemes and Compactness},
  author={Asuman G{\"u}ven Aksoy and Jos{\'e} Mar{\'i}a Almira},
  journal={arXiv: Functional Analysis},
We present an overview of some results about characterization of compactness in which the concept of approximation scheme has had a role. In particular, we present several results that were proved by the second author, jointly with Luther, a decade ago, when these authors were working on a very general theory of approximation spaces. We then introduce and show the basic properties of a new concept of compactness, which was studied by the first author in the eighties, by using a generalized… 

On a theorem of Terzioğlu

  • A. Aksoy
  • Mathematics
  • 2019
The theory of compact linear operators acting on a Banach space has a classical core and is familiar to many. Perhaps less known is the characterization theorem of Terzioglu for compact maps. This


ABSTRACT We show that generalized approximation spaces can be used to describe the relatively compact sets of Banach spaces. This leads to compactness and convergence criteria in the approximation

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Approximation spaces, in their many presentations, are well known mathematical objects and many authors have studied them for long time. They were introduced by Butzer and Scherer in 1968 and,

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