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arXiv · 2211.17069

Brunn-Minkowski inequality for $\theta$-convolution bodies via Ball's bodies

David Alonso-Gutiérrez·Javier Martín Goñi
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Abstract

We consider the problem of finding the best function $\varphi_n:[0,1]\to\mathbb{R}$ such that for any pair of convex bodies $K,L\in\mathbb{R}^n$ the following Brunn-Minkowski type inequality holds $$ |K+_\theta L|^\frac{1}{n}\geq\varphi_n(\theta)(|K|^\frac{1}{n}+|L|^\frac{1}{n}), $$ where $K+_\theta L$ is the $\theta$-convolution body of $K$ and $L$. We prove a sharp inclusion of the family of Ball's bodies of an $\alpha$-concave function in its super-level sets in order to provide the best possible function in the range $\left(\frac{3}{4}\right)^n\leq\theta\leq1$, characterizing the equality cases.

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David Alonso-Gutiérrez, Javier Martín Goñi. 2022-11-30. Brunn-Minkowski inequality for $\theta$-convolution bodies via Ball's bodies. https://arxiv.org/abs/2211.17069

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