19

Answers
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14
Does every non-empty set admit a group structure (in ZF)?
10
Forcing as a tool to prove theorems
2
Lower Bounds in Theoretical Computer Science
2
Distinct well-orderings of the same set
24
Does every set admit a rigid binary relation? (and how is this related to the Axiom of Choice?) (2)
9
Uses of bisimulation outside of computer science.
4
Singular Cardinals, and A Strange Question.
4
Cantor-Bernstein for notions of forcing
4
Is it possible for countably closed forcing to collapse $\aleph_2$ to $\aleph_1$ without collapsing the continuum?
10
If Q is a subset of the plane of size less than continuum, then does every closed F in Q extend to a closed connected G in the plane with the same trace on Q? (Or is this independent of ZFC?)
11
How can an ultrapower of a model of ZFC be “ill-founded” yet still satisfy ZFC?
7
Model of ZF + $\neg$C in which Solovay’s Theorem on stationary sets fails?
6
Determinacy interchanging the roles of both players
8
Background for classic forcing
7
Difference between Laver’s and Mathias’s forcing
7
Subsets of sequences of natural numbers vs. strategies under ZFC
2
a result about Laver property
3
A proof for cof(C,M)=cov(M)
5
Is $sat(I)$ always a regular cardinal?