New reals: Can live with them, can live without them
Logic
2015-09-07 v3
Abstract
We give a self-contained proof of the preservation theorem for proper countable support iterations known as "tools-preservation," "Case A" or "first preservation theorem" in the literature. We do not assume that the forcings add reals.
Cite
@article{arxiv.math/0505471,
title = {New reals: Can live with them, can live without them},
author = {Martin Goldstern and Jakob Kellner},
journal= {arXiv preprint arXiv:math/0505471},
year = {2015}
}
Comments
(an incorrect claim following Fact 2.3 was removed)