activity
20202023
most citedA Categorical Notion of Precompact Expansion

8 citations · 8 across the 6 of their papers we have counts for

collaborators

6 papers

math.CT2023

Tukey reducibility for categories -- In search of the strongest statement in finite Ramsey theory

Keegan Dasilva Barbosa, Dragan Mašulović

Every statement of the Ramsey theory of finite structures corresponds to the fact that a particular category has the Ramsey property. We can, then, compare the strength of Ramsey s…

math.LO2023

Box Ramsey and Canonical Colourings

Keegan Dasilva Barbosa

This paper introduces the concept of a productive notion of big Ramsey degree and showcases its versatility through a handful of applications. The main focus is notably providing s…

math.LO2023

A short note on the characterization of countable chains with finite big Ramsey spectra

Keegan Dasilva Barbosa, Dragan Mašulović, Rajko Nenadov

In this short note we confirm the deep structural correspondence between the complexity of a countable scattered chain (= strict linear order) and its big Ramsey combinatorics: we…

math.LO2021

Borel Colouring Bad Sequences

Keegan Dasilva Barbosa

Every better quasi-order codifies a Borel graph that does not contain a copy of the shift graph. It is known that there is a better quasi-order that codes a Borel graph with infini…

math.LO2020

A Decomposition Theorem for Aronszajn Lines

Keegan Dasilva Barbosa

We show that under the proper forcing axiom the class of all Aronszajn lines behave like -scattered orders under the embeddability relation. In particular, we are able to show t…

math.CO2020★ 8 cited

A Categorical Notion of Precompact Expansion

Keegan Dasilva Barbosa

We generalize the notion of relational precompact expansions of Fraïssé classes via functorial means, inspired by the technique outlined by Laflamme, Nguyen Van Thé and Sauer in th…