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11 votes
2 answers
483 views

The "strong" measure number

Beyond measure zero we have yet another measure-y notion of smallness: strong measure zero. A set $S\subseteq\mathbb{R}$ is strong measure zero if, for any $f:\mathbb{N}\rightarrow\mathbb{R}_{>0}$, ...
Noah Schweber's user avatar
9 votes
0 answers
242 views

Is this cardinal characteristic trivial? (Number of strategies needed to guarantee at least one win)

(Previously asked at MSE.) Let the determinacy number, $\mathfrak{g}$ (for "game"), be the smallest cardinal such that for every (two-player, perfect-information, length-$\omega$) game on $\...
Noah Schweber's user avatar
6 votes
1 answer
258 views

Do escaping sets "uniformly" cover dominating sets under determinacy?

For $\mathbb{A},\mathbb{B}\subseteq\mathcal{P}(\omega^\omega)$, say $\mathbb{A}$ spreads onto $\mathbb{B}$ iff there is some $F:\omega^\omega\rightarrow\omega^\omega$ such that for all $X\in\mathbb{A}$...
Noah Schweber's user avatar
4 votes
1 answer
151 views

Comparing bornologies for domination/escaping

Consider the following bornologies $\mathbb{D},\mathbb{E}$ on the set $\mathcal{N}$ of all functions from $\mathbb{N}$ to $\mathbb{N}$: $\mathbb{D}=\{A: \exists f\in\mathcal{N}\forall g\in A\exists m\...
Noah Schweber's user avatar
4 votes
1 answer
221 views

Comparing bornologies for cardinal characteristics via Borel maps

This question is "take 2" of this older one, following a suggestion of Francois Dorais. Consider the following bornologies $\mathbb{D},\mathbb{E}$ on the set $\mathcal{N}$ of all functions ...
Noah Schweber's user avatar