Will Brian

collaborators

4 papers

math.FA2024

Small-dimensional normed barrelled spaces

Will Brian, Christopher Stuart

We prove that every separable Banach space has a barrelled subspace with algebraic dimension $non (M)$ , which denotes the smallest cardinality of a non-meager subs…

math.LO2024

Conjugating trivial automorphisms of $P (N) / Fin$

Will Brian, Ilijas Farah

A trivial automorphism of the Boolean algebra $P (N) / Fin$ is an automorphism induced by the action of some function $N \to N$ . In…

math.LO2024

Does $P (ω) / fin$ know its right hand from its left?

Will Brian

Let $σ$ denote the shift automorphism on $P (ω) / fin$ , defined by setting $σ ([A]) = [A + 1]$ for all $A \subseteq ω$ . We show that the Continuum Hypothesis implies…

math.GN2023

Cardinal invariants of a meager ideal

Will Brian

Let $M_{X}$ denote the ideal of meager subsets of a topological space $X$ . We prove that if $X$ is a completely metrizable space without isolated points, then the smallest c…

Small-dimensional normed barrelled spaces

Conjugating trivial automorphisms of P(N)/Fin

Does P(ω)/fin know its right hand from its left?

Cardinal invariants of a meager ideal

Conjugating trivial automorphisms of $P (N) / Fin$

Does $P (ω) / fin$ know its right hand from its left?