The Ground Axiom

Joel David Hamkins

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arXiv · 1607.00723

The Ground Axiom

Joel David Hamkins

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Abstract

The ground axiom is the assertion that the set-theoretic universe is not obtainable by forcing over any inner model. Although this appears at first to be a second-order assertion, it is actually first-order expressible in the language of set theory. This article is the extended abstract for a talk at the 2005 Workshop in Set Theory at the Mathematisches Forschungsinstitut Oberwolfach.

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BibTeX RIS

Joel David Hamkins. 2016-07-04. The Ground Axiom. https://arxiv.org/abs/1607.00723

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