Approximation of starshaped sets using polynomials

Chiara Meroni; Jared Miller; Mauricio Velasco

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arXiv · 2505.24352

Approximation of starshaped sets using polynomials

Chiara Meroni·Jared Miller·Mauricio Velasco

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Abstract

We introduce polystar bodies: compact starshaped sets whose gauge or radial functions are expressible by polynomials, enabling tractable computations, such as that of intersection bodies. We prove that polystar bodies are uniformly dense in starshaped sets and obtain asymptotically optimal approximation guarantees. We develop tools for the construction of polystar approximations and illustrate them via several computational examples, including numerical estimations of largest volume slices and widths.

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Chiara Meroni, Jared Miller, Mauricio Velasco. 2025-05-30. Approximation of starshaped sets using polynomials. https://arxiv.org/abs/2505.24352

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