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arXiv · 2504.04902

Constructibility real degrees in the side-by-side Sacks model

Lorenzo Notaro
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Abstract

We study the join-semilattice of constructibility real degrees in the side-by-side Sacks model, the model of set theory obtained by forcing with a countable-support product of infinitely many Sacks forcings over the constructible universe. In particular, we prove that in the side-by-side Sacks model the join-semilattice of constructibility real degrees is rigid, i.e. it does not have non-trivial automorphisms.

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Lorenzo Notaro. 2025-04-07. Constructibility real degrees in the side-by-side Sacks model. https://doi.org/10.1016/j.apal.2026.103722

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