New posts in Ultrafilters

Multiplicative and additive groups of the field $(\prod_{n\in\omega}\mathbb{Z}/p_n\mathbb{Z})/\simeq_{\cal U}$

Ultrafilters as a double dual

A property of an ultrafilter

Ideals on $\mathbb N$ and large sets that have small intersection

Description of $\big(\ell^\infty(\mathbb N)\big)^{\!*}$ via ultrafilters

Stone–Čech Compactification of $\mathbb{Z}$ with Fürstenberg Topology

An Extender is a Generalization of an Ultrafilter?

Axiom of Choice: Ultrafilter vs. Vitali set

Reference Request: Independence of the ultrafilter lemma from ZF

"Transitivity" of the Stone-Cech compactification