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arXiv · 1204.6671

Delta-Decidability over the Reals

Sicun Gao·Jeremy Avigad·Edmund Clarke
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Abstract

Given any collection F of computable functions over the reals, we show that there exists an algorithm that, given any L_F-sentence φcontaining only bounded quantifiers, and any positive rational number δ, decides either "φis true", or "a δ-strengthening of φis false". Under mild assumptions, for a C-computable signature F, the δ-decision problem for bounded Σ_k-sentences in L_F resides in (Σ_k^P)^C. The results stand in sharp contrast to the well-known undecidability results, and serve as a theoretical basis for the use of numerical methods in decision procedures for nonlinear first-order theories over the reals.

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Sicun Gao, Jeremy Avigad, Edmund Clarke. 2012-04-30. Delta-Decidability over the Reals. https://arxiv.org/abs/1204.6671

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