Keeping the covering number of the null ideal small

Teruyuki Yorioka

Fundamenta Mathematicae (2015)

  • Volume: 231, Issue: 2, page 139-159
  • ISSN: 0016-2736

Abstract

top
It is proved that ideal-based forcings with the side condition method of Todorcevic (1984) add no random reals. By applying Judah-Repický's preservation theorem, it is consistent with the covering number of the null ideal being ℵ₁ that there are no S-spaces, every poset of uniform density ℵ₁ adds ℵ₁ Cohen reals, there are only five cofinal types of directed posets of size ℵ₁, and so on. This extends the previous work of Zapletal (2004).

How to cite

top

Teruyuki Yorioka. "Keeping the covering number of the null ideal small." Fundamenta Mathematicae 231.2 (2015): 139-159. <http://eudml.org/doc/283170>.

@article{TeruyukiYorioka2015,
abstract = {It is proved that ideal-based forcings with the side condition method of Todorcevic (1984) add no random reals. By applying Judah-Repický's preservation theorem, it is consistent with the covering number of the null ideal being ℵ₁ that there are no S-spaces, every poset of uniform density ℵ₁ adds ℵ₁ Cohen reals, there are only five cofinal types of directed posets of size ℵ₁, and so on. This extends the previous work of Zapletal (2004).},
author = {Teruyuki Yorioka},
journal = {Fundamenta Mathematicae},
keywords = {side condition method; random reals},
language = {eng},
number = {2},
pages = {139-159},
title = {Keeping the covering number of the null ideal small},
url = {http://eudml.org/doc/283170},
volume = {231},
year = {2015},
}

TY - JOUR
AU - Teruyuki Yorioka
TI - Keeping the covering number of the null ideal small
JO - Fundamenta Mathematicae
PY - 2015
VL - 231
IS - 2
SP - 139
EP - 159
AB - It is proved that ideal-based forcings with the side condition method of Todorcevic (1984) add no random reals. By applying Judah-Repický's preservation theorem, it is consistent with the covering number of the null ideal being ℵ₁ that there are no S-spaces, every poset of uniform density ℵ₁ adds ℵ₁ Cohen reals, there are only five cofinal types of directed posets of size ℵ₁, and so on. This extends the previous work of Zapletal (2004).
LA - eng
KW - side condition method; random reals
UR - http://eudml.org/doc/283170
ER -

NotesEmbed ?

top

You must be logged in to post comments.

To embed these notes on your page include the following JavaScript code on your page where you want the notes to appear.

Only the controls for the widget will be shown in your chosen language. Notes will be shown in their authored language.

Tells the widget how many notes to show per page. You can cycle through additional notes using the next and previous controls.

    
                

Note: Best practice suggests putting the JavaScript code just before the closing </body> tag.