Countable Fan Tightness and Selection Games in Group-Valued Function Spaces

Souvik Mandal; Ankur Sarkar

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arXiv · 2604.23671

Countable Fan Tightness and Selection Games in Group-Valued Function Spaces

Souvik Mandal·Ankur Sarkar

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Abstract

Game-theoretic characterizations of selection principles provide a powerful framework for analyzing covering properties through strategic interactions. For a Tychonoff space $X$ and a non-trivial metrizable arc-connected topological group $G$, we prove that Player~II has a winning strategy in the $Ω$-Menger game on $X$ if and only if Player~II has a winning strategy in the countable fan tightness game on $C_p(X, G)$ at the identity function. The analogous equivalence is established between the $Ω$-Rothberger game on $X$ and the countable strong fan tightness game on $C_p(X, G)$ at the identity function. These results extend the game-theoretic characterizations of Clontz from $G = \mathbb{R}$ to arbitrary metrizable arc-connected groups, and lift the selection-principle equivalences of Kočinac to the game-theoretic setting. As consequences, we establish that the game-theoretic tightness properties of $C_p(X,G)$ are independent of $G$, preserved under $G$-equivalence, and remain valid for Markov strategies.

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Souvik Mandal, Ankur Sarkar. 2026-04-26. Countable Fan Tightness and Selection Games in Group-Valued Function Spaces. https://arxiv.org/abs/2604.23671

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