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arXiv · 2302.10568

Inequalities for the quermassintegrals of sections of convex bodies

Dimitris-Marios Liakopoulos
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Abstract

We provide general estimates which compare the quermassintegrals of a convex body $K$ in ${\mathbb R}^n$ with the averages of the corresponding quermassintegrals of the $k$-codimensional sections of $K$ over $G_{n,n-k}$. An example is the inequality $$\alpha_{n,k,j}\frac{W_j(K)}{|K|}\leq\int_{G_{n,n-k}}\frac{W_j(K\cap F)}{|K\cap F|}d\nu_{n,n-k}(F)\leq \beta_{n,k,j}\frac{W_j(K)}{|K|}$$ where the constants $\alpha_{n,k,j}$ and $\beta_{n,k,j}$ depend only on $n,k$ and $j$, which holds true for any centrally symmetric convex body $K$ in ${\mathbb R}^n$ and any $0\leq j\leq n-k-1\leq n-1$. Using these estimates we obtain some positive results for suitable versions of the slicing problem for the quermassintegrals of a convex body.

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Dimitris-Marios Liakopoulos. 2023-02-21. Inequalities for the quermassintegrals of sections of convex bodies. https://arxiv.org/abs/2302.10568

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