The measure algebra adding $θ$-many random reals is $θ$-FAM-linked

Diego A. Mejía, Andrés Felipe Uribe-Zapata

Published 2023-12-20Version 1

The notion of $\theta$-FAM-linkedness, introduced in the second author's master thesis, is a formalization of the notion of strong FAM limits for intervals, whose initial form and applications have appeared in the work of Saharon Shelah, Jakob Kellner, and Anda T\u{a}nasie, for controlling cardinals characteristics of the continuum in ccc forcing extensions. This generalization was successful in such a thesis to establish a general theory of iterated forcing using finitely additive measures. In this paper, using probability theory tools developed in the same thesis, we refine Saharon Shelah's proof of the fact that random forcing is $\sigma$-FAM-linked and prove that any complete Boolean algebra with a strictly positive probability measure satisfying the $\theta$-density property is $\theta$-FAM-linked. As a consequence, we get a new collection of examples of $\theta$-FAM-linked forcing notions: the measure algebra adding $\theta$-many random reals.