The Weak Kőnig Lemma, Brouwer’s Fan Theorem, De Morgan’s Law, and Dependent Choice

• Authors: Josef Berger , Hajime Ishihara , Peter Schuster
• Languages of publication: PL

Abstracts

PL

The standard omniscience principles are interpreted in a systematic way within the context of binary trees. With this dictionary at hand we revisit the weak Konig lemma (WKL) and Brouwer’s fan theorem (FAN). We first study how one can arrive from FAN at WKL, and then give a direct decomposition, without coding, of WKL into the lesser limited principle of omniscience and an instance of the principle of dependent choices. As a complement we provide, among other equivalents of the standard omniscience principles, a uniform method to formulate most of them.

Keywords

PL

• Publisher: [unknown2]
• Journal: Reports on Mathematical Logic
• Year: 2012
• Volume: 47

Dates

published

2012

online

07 - 07 - 2015

Contributors

author

Josef Berger

author

Hajime Ishihara

author

Peter Schuster