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Two- versus three-dimensional connectivity testing of first-order queries to semi-algebraic sets

Floris Geerts·Lieven Smits·Jan Van den Bussche
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Abstract

This paper addresses the question whether one can determine the connectivity of a semi-algebraic set in three dimensions by testing the connectivity of a finite number of two-dimensional ``samples'' of the set, where these samples are defined by first-order queries. The question is answered negatively for two classes of first-order queries: cartesian-product-free, and positive one-pass.

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Floris Geerts, Lieven Smits, Jan Van den Bussche. 2003-08-01. Two- versus three-dimensional connectivity testing of first-order queries to semi-algebraic sets. https://doi.org/10.1007/s00236-005-0171-5

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