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arXiv · 1502.01730

A polynomial regularity lemma for semi-algebraic hypergraphs and its applications in geometry and property testing

Jacob Fox·Janos Pach·Andrew Suk
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Abstract

Fox, Gromov, Lafforgue, Naor, and Pach proved a regularity lemma for semi-algebraic $k$-uniform hypergraphs of bounded complexity, showing that for each $\epsilon>0$ the vertex set can be equitably partitioned into a bounded number of parts (in terms of $\epsilon$ and the complexity) so that all but an $\epsilon$-fraction of the $k$-tuples of parts are homogeneous. We prove that the number of parts can be taken to be polynomial in $1/\epsilon$. Our improved regularity lemma can be applied to geometric problems and to the following general question on property testing: is it possible to decide, with query complexity polynomial in the reciprocal of the approximation parameter, whether a hypergraph has a given hereditary property? We give an affirmative answer for testing typical hereditary properties for semi-algebraic hypergraphs of bounded complexity.

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Jacob Fox, Janos Pach, Andrew Suk. 2015-02-05. A polynomial regularity lemma for semi-algebraic hypergraphs and its applications in geometry and property testing. https://arxiv.org/abs/1502.01730

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