Authors
A.W. Swan
Date (dd-mm-yyyy)
2018-04-12
Title
On Dividing by Two in Constructive Mathematics
Publication Year
2018-04-12
Document type
Working paper
Abstract
A classic result due to Bernstein states that in set theory with classical logic, but without the axiom of choice, for all
sets X and Y, if X×2≅Y×2 then also X≅Y. We show that this cannot be done in constructive mathematics by giving some examples
of toposes where it fails.
Permalink
https://hdl.handle.net/11245.1/b343a9cd-f4b3-4313-bc35-e833ca406f81