Solving clustered low-rank semidefinite programs arising from polynomial optimization
Nando Leijenhorst, David de Laat
TL;DR
This work develops a high-precision primal-dual interior-point method that exploits clustered low-rank semidefinite constraints arising from sums-of-squares formulations of polynomial optimization problems in discrete geometry. By integrating sampling-based representations, symmetry reduction, and a greedy procedure for selecting good sample points and bases, the approach achieves substantial speedups and improved numerical stability over prior solvers. The authors implement a Julia-based solver with fast matrix multiplication and demonstrate the method on two core applications: the three-point kissing-number bound and the binary sphere packing bound, obtaining a 28x speedup in the kissing-number case and extending bounds to higher degrees and dimensions. These advances enable solving previously intractable high-degree instances, yielding improved bounds in dimensions $11$--$23$ and providing new insights into conditioning and convergence for matrix polynomial programs via clustered low-rank structure.
Abstract
We study a primal-dual interior point method specialized to clustered low-rank semidefinite programs requiring high precision numerics, which arise from certain multivariate polynomial (matrix) programs through sums-of-squares characterizations and sampling. We consider the interplay of sampling and symmetry reduction as well as a greedy method to obtain numerically good bases and sample points. We apply this to the computation of three-point bounds for the kissing number problem, for which we show a significant speedup. This allows for the computation of improved kissing number bounds in dimensions $11$ through $23$. The approach performs well for problems with bad numerical conditioning, which we show through new computations for the binary sphere packing problem.
