A preprint on arXiv (not yet peer-reviewed) examines whether trajectory-based Shannon entropy can serve as a better or complementary tool to the largest Lyapunov exponent for diagnosing chaos in gravitational dynamics. Researchers computed both the largest Lyapunov exponent and a coarse-grained Shannon entropy for ensembles of trajectories in the Henon-Heiles potential (a classic two-degree-of-freedom model) and for test-particle orbits in live N-body simulations of a Plummer model representing star clusters. They tracked how these measures changed with orbital energy and, in the N-body runs, with varying particle numbers. In Henon-Heiles, the entropy closely tracked the shift from weak to widespread chaos much like the Lyapunov exponent; in the N-body systems, both flagged stronger chaos in tightly bound orbits, but entropy dropped as particle count rose while the Lyapunov exponent stayed nearly flat. Limitations include the use of specific idealized models, computational ensembles without observational data, and no fixed sample size reported beyond general trajectory sets. Source: https://arxiv.org/abs/2603.24675