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arXiv · 1603.07259

On the characterization of models of H*: The semantical aspect

Flavien Breuvart
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Abstract

We give a characterization, with respect to a large class of models of untyped lambda-calculus, of those models that are fully abstract for head-normalization, i.e., whose equational theory is H* (observations for head normalization). An extensional K-model $D$ is fully abstract if and only if it is hyperimmune, {\em i.e.}, not well founded chains of elements of D cannot be captured by any recursive function. This article, together with its companion paper, form the long version of [Bre14]. It is a standalone paper that presents a purely semantical proof of the result as opposed to its companion paper that presents an independent and purely syntactical proof of the same result.

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Flavien Breuvart. 2016-03-23. On the characterization of models of H*: The semantical aspect. https://doi.org/10.2168/lmcs-12(2:4)2016

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