🤖 AI Summary
This work addresses the instability of conventional lexicographic-order-based braid computations when input trajectories exhibit numerical uncertainty. To overcome this limitation, the authors propose a novel input model grounded in separation predicates, which transforms error-prone trajectories—such as those arising from tracking roots of polynomials with complex coefficients—into verifiably exact braid representations. This approach establishes the first theoretical framework for braid computation tailored to approximate data, replacing the fragile lexicographic ordering with robust separation predicates. By integrating techniques from computational topology and numerical algebra, the method reliably determines the correct crossing order of paths under perturbations. Experimental results demonstrate that the framework accurately and stably recovers exact braid structures from real-world approximate trajectory data, achieving both theoretical rigor and practical robustness.
📝 Abstract
We study the theoretical and practical aspects of computing braids described by approximate descriptions of paths in the plane. Exact algorithms rely on the lexicographic ordering of the points in the plane, which is unstable under numerical uncertainty. Instead, we formalize an input model for approximate data, based on a separation predicate. It applies, for example, to paths obtained by tracking the roots of a parametrized polynomial with complex coefficients, thereby connecting certified path tracking outputs to exact braid computation.