# Sh:485

- Abraham, U., & Shelah, S. (2002).
*Coding with ladders a well ordering of the reals*. J. Symbolic Logic,**67**(2), 579–597. arXiv: math/0104195 DOI: 10.2178/jsl/1190150099 MR: 1905156 -
Abstract:

Any model of ZFC + GCH has a generic extension (made with a poset of size \aleph_2) in which the following hold: MA + 2^{\aleph_0}=\aleph_2+*there exists a*\Delta^2_1-*well ordering of the reals.*The proof consists in iterating posets designed to change at will the guessing properties of ladder systems on \omega_1. Therefore, the study of such ladders is a main concern of this article. - Version 2001-03-24_10 (30p) published version (20p)

Bib entry

@article{Sh:485, author = {Abraham, Uri and Shelah, Saharon}, title = {{Coding with ladders a well ordering of the reals}}, journal = {J. Symbolic Logic}, fjournal = {The Journal of Symbolic Logic}, volume = {67}, number = {2}, year = {2002}, pages = {579--597}, issn = {0022-4812}, mrnumber = {1905156}, mrclass = {03E35 (03E50)}, doi = {10.2178/jsl/1190150099}, note = {\href{https://arxiv.org/abs/math/0104195}{arXiv: math/0104195}}, arxiv_number = {math/0104195} }