English

Free Entropy Dimension in Amalgamated Free Products

Operator Algebras 2014-02-26 v5

Abstract

We calculate the microstates free entropy dimension of natural generators in an amalgamated free product of certain von Neumann algebras, with amalgamation over a hyperfinite subalgebra. In particular, some `exotic' Popa algebra generators of free group factors are shown to have the expected free entropy dimension. We also show that microstates and non--microstates free entropy dimension agree for generating sets of many groups. In the appendix by Wolfgang Lueck, the first L^2-Betti number for certain amalgamated free products of groups is calculated.

Keywords

Cite

@article{arxiv.math/0609080,
  title  = {Free Entropy Dimension in Amalgamated Free Products},
  author = {Nathanial P. Brown and Kenneth J. Dykema and Kenley Jung},
  journal= {arXiv preprint arXiv:math/0609080},
  year   = {2014}
}

Comments

The second revised version significantly generalized the main result of the original one, (see the abstract) and contains a new appendix by Wolfgang Lueck. The third and fourth revisions correct some minor mistakes. The fifth version adds a result about embeddability of amalgmated free products

R2 v1 2026-07-22T17:41:52.040Z