How to compute the volume in low dimension?
Arjan Cornelissen, Simon Apers, Sander Gribling
TL;DR
This work analyzes volume estimation for convex bodies in the low-dimensional, high-precision regime via a membership oracle, deriving tight query-complexity characterizations across deterministic, randomized, and quantum models. It shows that convex set estimation and $\varepsilon$-kernel construction admit $\widetilde{\Theta}(\varepsilon^{-(d-1)/2})$ membership-queries irrespective of randomness or quantum power, while volume estimation benefits from randomness and quantum speedups: $\widetilde{O}(\varepsilon^{-2(d-1)/(d+3)})$ (randomized) and $\widetilde{O}(\varepsilon^{-(d-1)/(d+1)})$ (quantum). The key techniques combine a deterministic rounding to obtain a well-rounded body, projection-based $\varepsilon$-kernel construction, and inner/outer approximations with sampling or amplitude estimation for volume, together with Dudley-type spherical-cap packings to prove matching lower bounds. The results provide a complete low-dimensional theory for volume estimation with membership oracles and clarify the potential of quantum and randomized accelerations in this setting, complementing the extensive high-dimensional literature. Overall, the work reveals sharp, dimension-dependent trade-offs: randomness and quantum advantages vanish for convex-set tasks but yield meaningful reductions for volume estimation in fixed dimension.
Abstract
Estimating the volume of a convex body is a canonical problem in theoretical computer science. Its study has led to major advances in randomized algorithms, Markov chain theory, and computational geometry. In particular, determining the query complexity of volume estimation to a membership oracle has been a longstanding open question. Most of the previous work focuses on the high-dimensional limit. In this work, we tightly characterize the deterministic, randomized and quantum query complexity of this problem in the high-precision limit, i.e., when the dimension is constant.
