On k ‐point configuration sets with nonempty interior
On k ‐point configuration sets with nonempty interior
复制标题
内部非空的 k 点配置集
DOI:
10.1112/mtk.12114
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发表时间:
2022
期刊:
影响因子:
0.8
通讯作者:
Taylor, Krystal
中科院分区:
文献类型:
--
作者:
Greenleaf, Allan;Iosevich, Alex;Taylor, Krystal
We give conditions fork‐point configuration sets of thin sets to have nonempty interior, applicable to a wide variety of configurations. This is a continuation of our earlier work (J. Geom. Anal.31(2021), 6662–6680) on 2‐point configurations, extending a theorem of Mattila and Sjölin (Math. Nachr.204(1999), 157–162) for distance sets in Euclidean spaces. We show that for a general class ofk‐point configurations, the configuration set of ak‐tuple of sets, E1,⋯,Ek$E_1,\,\dots ,\, E_k$, has nonempty interior provided that the sum of their Hausdorff dimensions satisfies a lower bound, dictated by optimizingL2‐Sobolev estimates of associated generalized Radon transforms over all nontrivial partitions of thekpoints into two subsets. We illustrate the general theorems with numerous specific examples. Applications to 3‐point configurations include areas of triangles in R2$\mathbb {R}^2$ or the radii of their circumscribing circles; volumes of pinned parallelepipeds in R3$\mathbb {R}^3$; and ratios of pinned distances in R2$\mathbb {R}^2$ and R3$\mathbb {R}^3$. Results for 4‐point configurations include cross‐ratios on R$\mathbb {R}$, pairs of areas of triangles determined by quadrilaterals in R2$\mathbb {R}^2$, and dot products of differences in Rd$\mathbb {R}^d$.