Hyperplane mass equipartition problem and the shielding functions of Ramos

Abstract

We give a proof of the result of Edgar Ramos which claims that two finite, continuous Borel measures $\mu_1$ and $\mu_2$ defined on $\mathbb{R}^5$ admit an equipartition by a collection of three hyperplanes. Our proof illuminates one of the central methods developed and used in our earlier papers and may serve as a good `test case' for addressing (and resolving) the `issues' raised in the paper "Topology of the Gr\"unbaum-Hadwiger-Ramos hyperplane mass partition problem", arXiv:1502.02975 [math.AT]. We also offer a degree-theoretic interpretation of the `parity calculation method' developed by Ramos and demonstrate that, up to minor corrections or modifications, it remains a rigorous and powerful tool for proving results about mass equipartitions.