Lemmas | Covering lemmas | Inner model theory

Covering lemma

In the foundations of mathematics, a covering lemma is used to prove that the non-existence of certain large cardinals leads to the existence of a canonical inner model, called the core model, that is, in a sense, maximal and approximates the structure of the von Neumann universe V. A covering lemma asserts that under some particular anti-large cardinal assumption, the core model exists and is maximal in a sense that depends on the chosen large cardinal. The first such result was proved by Ronald Jensen for the constructible universe assuming 0# does not exist, which is now known as Jensen's covering theorem. (Wikipedia).

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Related pages

Singular cardinals hypothesis | Large cardinal | Constructible universe | Foundations of mathematics | Measurable cardinal | Von Neumann universe | Zero sharp | Core model | Inner model | Jensen's covering theorem