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arXiv · 1410.5197

The field of the Reals and the Random Graph are not Finite-Word Ordinal-Automatic

Alexander Kartzow
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Abstract

Recently, Schlicht and Stephan lifted the notion of automatic-structures to the notion of (finite-word) ordinal-automatic structures. These are structures whose domain and relations can be represented by automata reading finite words whose shape is some fixed ordinal $α$. We lift Delhommé's relative-growth-technique from the automatic and tree-automatic setting to the ordinal-automatic setting. This result implies that the random graph is not ordinal-automatic and infinite integral domains are not ordinal-automatic with respect to ordinals below $ω_1+ω^ω$ where $ω_1$ is the first uncountable ordinal.

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Alexander Kartzow. 2014-10-20. The field of the Reals and the Random Graph are not Finite-Word Ordinal-Automatic. https://arxiv.org/abs/1410.5197

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