Gabriel Fernandes

collaborators

4 papers

math.GN2026

Cardinality Bounds for Hausdorff SDL Spaces

Gabriel Fernandes, João Marcelo Maciel Messias

We establish the cardinal inequality $|X|\leq 2^{t(X)Hψ(X)}$ for every Hausdorff SDL space $X$, where $t(X)$ and $Hψ(X)$ denote the tightness and the Hausdorff pseudocharac…

math.GN2026

Ray and end spaces: characterizations and classification up to homeomorphism

Matheus Duzi, Gabriel Fernandes, Paulo Magalhães Júnior

We provide a combinatorial characterization for pairs of order-theoretic trees with homeomorphic ray spaces, answering an open problem proposed by Kurkofka ad Pitz. This solution i…

math.LO2024

Remarks on Halin's end-degree Conjecture

Gabriel Fernandes

We prove new instances of Halin's end degree conjecture (HC) in ZFC. In particular, we show that there is a proper class of cardinals kappa for which Halin's conjecture holds, answ…

math.LO2024

Ray inflations of $ω_{1}$ -trees and ends of degree $ℵ_{1}$

Leandro Aurichi, Gabriel Fernandes, Paulo Magalhães Júnior

We prove the followings result for ray inflations of sparse graphs on $ω_{1}$ -trees. First, let $T$ and $S$ be pruned $ω_{1}$ -trees, let $G_{T}$ be a sparse $T$ -graph, and let $G_{S}$ be a…

Cardinality Bounds for Hausdorff SDL Spaces

Ray and end spaces: characterizations and classification up to homeomorphism

Remarks on Halin's end-degree Conjecture

Ray inflations of ω1​-trees and ends of degree ℵ1​

Ray inflations of $ω_{1}$ -trees and ends of degree $ℵ_{1}$