18

Answers

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2

Examples of conjectures that were widely believed to be true but later proved false

8

2D Problems Which are Easier to Solve in 3D

5

Failure of the GCH

2

Parts of Set Theory immune to independence

12

What’s the difference between ZFC+Grothendieck, ZFC+inaccessible cardinals and Tarski-Grothendieck set theory?

2

Theorems proved with AD whose proof is also known in the ZF world

5

Why can’t an explicit well-ordering of the reals be ruled out in ZF?

4

Is the Mostowski collapse natural?

4

In search of a set theory with specific properties

1

Tarski-Grothendieck set theory, the axiom of pairing and the axiom of specification

3

Weakly homogeneous trees under AD

2

Models of $AD$ different from $L(\mathbb{R})$

2

set existence question

5

To find an element of a $\Pi^1_1$ set

2

Strong ideals that are not pre-saturated

3

Relation between $\neg \square(\kappa)$ and the tree property at $\kappa$.

4

$\Theta$ and the Hartogs of $2^\mathbb R$

10

Countable structures with uncountable many automorphisms