Two variants of minimality in forcing extensions

Martin Goldstern; Tatsuya Goto

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arXiv · 2609.17153

Two variants of minimality in forcing extensions

Martin Goldstern·Tatsuya Goto

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Abstract

We introduce d-minimal and b-minimal extensions, two weakenings of minimality based respectively on eventual domination and infinitely often domination. We prove that the generic extensions obtained by the full Mathias forcing and by Mathias forcing relative to Ramsey ultrafilters are d-minimal, whereas Hechler extensions are b-minimal. We also construct a d-minimal extension that is weakly $ω^ω$-bounding but neither minimal nor $ω^ω$-bounding, and realize every constellation of these properties compatible with their natural implications.

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BibTeX RIS

Martin Goldstern, Tatsuya Goto. 2026-09-15. Two variants of minimality in forcing extensions. https://arxiv.org/abs/2609.17153

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