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arXiv · 1910.11230

Counting siblings in universal theories

Samuel Braunfeld·Michael C. Laskowski
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Abstract

We show that if a countable structure $M$ in a finite relational language is not cellular, then there is an age-preserving $N \supseteq M$ such that $2^{\aleph_0}$ many structures are bi-embeddable with $N$. The proof proceeds by a case division based on mutual algebraicity.

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BibTeXRIS

Samuel Braunfeld, Michael C. Laskowski. 2021-04-26. Counting siblings in universal theories. https://doi.org/10.1017/jsl.2022.3

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