activity
20152022
collaborators

8 papers

math.LO2022

Forcing constellations of Cichoń's diagram by using the Tukey order

Miguel A. Cardona, Diego A. Mejía

We use known finite support iteration techniques to present various examples of models where several cardinal characteristics of Cichoń's diagram are pairwise different. We show so…

math.CV2019

Level sets of the Hyperbolic Derivative for analytic self-maps of the unit disk

Juan Arango, Hugo Arbeláez, Diego Mejía

Let the function be holomorphic in the unit disk of the complex plane and let . We study the level sets and the criti…

math.LO2019

Cichoń's maximum without large cardinals

Martin Goldstern, Jakob Kellner, Diego A. Mejía +1

Cichoń's diagram lists twelve cardinal characteristics (and the provable inequalities between them) associated with the ideals of null sets, meager sets, countable sets, and -co…

math.LO2019

Controlling classical cardinal characteristics while collapsing cardinals

Martin Goldstern, Jakob Kellner, Diego A. Mejía +1

Given a forcing notion that forces certain values to several classical cardinal characteristics of the reals, we show how we can compose with a collapse (of a cardinal $λ>κ…

math.LO2019

A note on "Another ordering of the ten cardinal characteristics in Cichoń's Diagram" and further remarks

Diego Alejandro Mejía

In this note, we relax the hypothesis of the main results in Kellner-Shelah-Tǎnasie's "Another ordering of the ten cardinal characteristics in Cichoń's diagram".

math.LO2018

Filter-linkedness and its effect on preservation of cardinal characteristics

Jörg Brendle, Miguel A. Cardona, Diego A. Mejía

We introduce the property ``-linked'' of subsets of posets for a given free filter on the natural numbers, and define the properties ``--linked'' and ``--Knaster…