English

Lipschitz retraction of finite subsets of Hilbert spaces

Metric Geometry 2015-12-30 v2

Abstract

Finite subset spaces of a metric space XX form a nested sequence under natural isometric embeddings X=X(1)X(2)X=X(1)\subset X(2)\subset\dots. We prove that this sequence admits Lipschitz retractions X(n)X(n1)X(n)\to X(n-1) when XX is a Hilbert space.

Keywords

Cite

@article{arxiv.1406.6742,
  title  = {Lipschitz retraction of finite subsets of Hilbert spaces},
  author = {Leonid V. Kovalev},
  journal= {arXiv preprint arXiv:1406.6742},
  year   = {2015}
}

Comments

Specializes the result from v1 to Hilbert spaces. The problem remains open for general Hadamard spaces