New posts in Set Theory

Definitions of $2$ in set theory?

Is every sigma-algebra of cardinality $2^\kappa$ for some cardinal $\kappa$?

What is a good argument for rejecting the axiom of choice?

A co-meagre topology on $\aleph_{\omega}$

Does every uncountable Borel subset of $\mathbb R$ contains a perfect subset？

How do the consequences of Russell's paradox extend beyond universal comprehension principle as far as the set of all sets problem?

¿Is, for $1\le n<\omega ,\;(\omega+n)^{\omega}=\omega^{\omega}$?

Is $\aleph_{1}^{\aleph_0}<\aleph_{2}^{\aleph_0}$ equivalent to the Continuum Hypothesis?

Models of set theory where not every set can be linearly ordered

How are sets defined in reverse mathematics?