Skip to main content
Search type Search syntax
Tags [tag]
Exact "words here"
Author user:1234
user:me (yours)
Score score:3 (3+)
score:0 (none)
Answers answers:3 (3+)
answers:0 (none)
isaccepted:yes
hasaccepted:no
inquestion:1234
Views views:250
Code code:"if (foo != bar)"
Sections title:apples
body:"apples oranges"
URL url:"*.example.com"
Saves in:saves
Status closed:yes
duplicate:no
migrated:no
wiki:no
Types is:question
is:answer
Exclude -[tag]
-apples
For more details on advanced search visit our help page
Results tagged with
Search options not deleted user 491676

forcing, large cardinals, descriptive set theory, infinite combinatorics, cardinal characteristics, forcing axioms, ultrapowers, measures, reflection, pcf theory, models of set theory, axioms of set theory, independence, axiom of choice, continuum hypothesis, determinacy, Borel equivalence relations, Boolean-valued models, embeddings, orders, relations, transfinite recursion, set theory as a foundation of mathematics, the philosophy of set theory.

3 votes
1 answer
116 views

Forcing equivalence and equal generic extensions

Two forcing notions $\Bbb P$ and $\Bbb Q$ could be defined to be forcing equivalent if the associated complete Boolean algebras are isomorphic (so, the CBA's formed by considering the regular opens of …
Tristan vd Vlugt's user avatar
7 votes
0 answers
128 views

What is the forcing $\bf U$ from Bartoszyński-Judah?

In Set Theory - on the structure of the Real Line by Bartoszyński & Judah, a forcing notion $\bf U$ is mentioned on page 339, allegedly corresponding to $\rm{cof}(\cal N)$ as it has several properties …
Tristan vd Vlugt's user avatar
4 votes
1 answer
128 views

Coherent sequence of ultrafilters in iterated forcing extensions

Remember that if $\kappa$ is strongly compact, then any ${<}\kappa$-complete filter extends to a ${<}\kappa$-complete ultrafilter. Let $\Bbb P_\delta=\langle\Bbb P_\alpha,\dot{\Bbb Q}_\alpha\mid \alph …
Tristan vd Vlugt's user avatar
4 votes
2 answers
239 views

Extending normal filters

If $F$ is a $\kappa$-complete filter on some set $S$, and $F$ is generated by a basis of size $\lambda$, then $F$ extends to a $\kappa$-complete ultrafilter on $S$ when we assume that $\kappa$ is $\la …
Tristan vd Vlugt's user avatar
6 votes
0 answers
272 views

Referring to the countability of $\Bbb Q$ as "Cantor's first diagonal argument"

I had a discussion with one of my students, who was convinced that they could prove something was countable using Cantor's diagonal argument. They were referring to (what I know as) Cantor's pairing f …
Tristan vd Vlugt's user avatar
5 votes
0 answers
122 views

Large set of almost disjoint functions on a product space

Given an increasing sequence of cardinals $\langle\kappa_\alpha\mid \alpha\in\kappa\rangle$, let $K=\prod_{\alpha\in\kappa} \kappa_\alpha$, then we call $f,g\in K$ eventually different if there exists …
Tristan vd Vlugt's user avatar