My education as a researcher is originally in Logic and Foundations, particularly in Set Theory and especially in infinitary combinatorics and consistency and independence proofs. Throughout my trajectory, I have also worked in the intersection of the aforementioned topics with algebra, analysis, and topology. Another recurrent theme in my research work is the way the world looks like when one does not assume the Axiom of Choice. A significant chunk of my work has dealt with additive combinatorics in the infinite realm, especially on uncountable structures. A thorough list of my multiple research lines, including links to the relevant papers, can be found in the section on research on this website.

^{1. My paternal surname is Fernández, and my maternal surname is Bretón; this is a distinction that English-speaking people are not familiar with and therefore they tend to get the whole thing wrong all the time. If you'd like to get it right, go read the relevant Wikipedia article, especially the "forms of address" subsection; basically, don't ever use "Bretón" unless you're willing to also use "Fernández" at the same time.↩} ^{2. If you're interested in these things, you can check out my genealogy.↩}