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arXiv · 1904.10360

Polarization, sign sequences and isotropic vector systems

Gergely Ambrus·Sloan Nietert
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Abstract

We determine the order of magnitude of the $n$th $\ell_p$-polarization constant of the unit sphere $S^{d-1}$ for every $n,d \geq 1$ and $p>0$. For $p=2$, we prove that extremizers are isotropic vector sets, whereas for $p=1$, we show that the polarization problem is equivalent to that of maximizing the norm of signed vector sums. Finally, for $d=2$, we discuss the optimality of equally spaced configurations on the unit circle.

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Gergely Ambrus, Sloan Nietert. 2019-07-13. Polarization, sign sequences and isotropic vector systems. https://doi.org/10.2140/pjm.2019.303.385

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