Inclusion modulo nonstationary
Abstract
A classical theorem of Hechler asserts that the structure (ωω,*) is universal in the sense that for any σ-directed poset P with no maximal element, there is a ccc forcing extension in which (ωω,*) contains a cofinal order-isomorphic copy of P. In this paper, we prove a consistency result concerning the universality of the higher analogue (,S): Theorem. Assume GCH. For every regular uncountable cardinal , there is a cofinality-preserving GCH-preserving forcing extension in which for every analytic quasi-order Q over and every stationary subset S of , there is a Lipschitz map reducing Q to (,S).
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