English

Matrix algebra of sets and variants of decomposition complexity

Metric Geometry 2017-12-19 v4 General Topology

Abstract

We introduce matrix algebra of subsets in metric spaces and we apply it to improve results of Yamauchi and Davila regarding Asymptotic Property C. Here is a representative result: Suppose XX is an \infty-pseudo-metric space and n0n\ge 0 is an integer. The asymptotic dimension of XX is at most nn if and only if for any real number r>0r > 0 and any integer m1m\ge 1 there is an augmented m×(n+1)m\times (n+1)-matrix M=[BA]\mathcal{M}=[\mathcal{B} |\mathcal{A}] (that means B\mathcal{B} is a column-matrix and A\mathcal{A} is an m×nm\times n-matrix) of subspaces of XX of scale-rr-dimension 00 such that MMT\mathcal{M}\cdot_\cap \mathcal{M}^T is bigger than or equal to the identity matrix and B(A,r)B(A,r)TB(\mathcal{A},r)\cdot_\cap B(\mathcal{A},r)^T is a diagonal matrix.

Keywords

Cite

@article{arxiv.1612.06771,
  title  = {Matrix algebra of sets and variants of decomposition complexity},
  author = {Jerzy Dydak},
  journal= {arXiv preprint arXiv:1612.06771},
  year   = {2017}
}

Comments

14 pages, a few typos are corrected, 3 exercises are added