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arXiv · 2501.13522

Fractional Divisibility of Spheres with Partially Generic Sets of Rotations

Jan Grebík·Christian Ikenmeyer·Oleg Pikhurko
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Abstract

We say that an r-tuple $(g_1,...,g_r)$ of special orthogonal $d\times d$ matrices fractionally divides the $(d-1)$-dimensional sphere $S$ if there is a non-constant function in $L^2(S)$ such that its translations by $g_1,...,g_r$ sum up to the constant-1 function. Our main result shows, informally speaking, that fractional divisibility is impossible if at least $r/2$ rotations are ``generic".

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Jan Grebík, Christian Ikenmeyer, Oleg Pikhurko. 2025-01-23. Fractional Divisibility of Spheres with Partially Generic Sets of Rotations. https://arxiv.org/abs/2501.13522

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