Spectral flatness and the volume of intersections of -ellipsoids
arXiv:2107.01097 · doi:10.1016/j.jco.2021.101617
Abstract
Motivated by classical works of Schechtman and Schmuckenschläger on intersections of -balls and recent ones in information-based complexity relating random sections of ellipsoids and the quality of random information in approximation problems, we study the threshold behavior of the asymptotic volume of intersections of generalized -ellipsoids. The non-critical behavior is determined under a spectral flatness (Wiener entropy) condition on the semi-axes. In order to understand the critical case at the threshold, we prove a central limit theorem for -norms of points sampled uniformly at random from a -ellipsoid, which is obtained under Noether's condition on the semi-axes.
2nd version with extended examples and their proofs