English

Extension dimensional approximation theorem

General Topology 2007-05-23 v2

Abstract

Let LL be a countable CW-complex and F ⁣:XYF\colon X\to Y be upper semicontinuous UV[L]UV^{[L]}-valued mapping of a paracompact space XX to a complete metric space YY. We prove that if XX is a C-space of extension dimension \edX[L]\ed X \le [L], then FF admits single-valued graph approximations. For L=SnL=S^n our result implies well-known approximation theorem for UVn1UV^{n-1}-valued mappings of nn-dimensional spaces. And for L={point}L=\{\rm point\} our theorem implies a theorem of Ancel on approximations of UVUV^\infty-valued mappings of C-spaces.

Keywords

Cite

@article{arxiv.math/0103061,
  title  = {Extension dimensional approximation theorem},
  author = {N. Brodsky and A. Chigogidze},
  journal= {arXiv preprint arXiv:math/0103061},
  year   = {2007}
}

Comments

7 pages, final version, minor corrections