Saved in:
Bibliographic Details
Main Author: Kowalczyk, Jacob
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2503.00310
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866912378407354368
author Kowalczyk, Jacob
author_facet Kowalczyk, Jacob
contents It is consistent with ZF + DC that there exists an ultrafilter $U$ on $ω$ such that two infinite ultraproducts of finite sets, $\prod A_n / U$ and $\prod B_n / U$, have the same cardinality if and only if $0 < \lim_U |A_n|/|B_n| < \infty$. In particular, this holds in $W[U]$, where $W$ is the Solovay Model and $U$ is $[ω]^ω$-generic.
format Preprint
id arxiv_https___arxiv_org_abs_2503_00310
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Cardinalities of Ultraproducts of Finite Sets in ZF + DC
Kowalczyk, Jacob
Logic
It is consistent with ZF + DC that there exists an ultrafilter $U$ on $ω$ such that two infinite ultraproducts of finite sets, $\prod A_n / U$ and $\prod B_n / U$, have the same cardinality if and only if $0 < \lim_U |A_n|/|B_n| < \infty$. In particular, this holds in $W[U]$, where $W$ is the Solovay Model and $U$ is $[ω]^ω$-generic.
title Cardinalities of Ultraproducts of Finite Sets in ZF + DC
topic Logic
url https://arxiv.org/abs/2503.00310