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Updated: May 31, 2026

Age-dependent Dynamics of Locomotion in Caenorhabditis elegans: A Lyapunov Exponent Analysis
Published on: September 23, 2025
Lagrangian coherent structures and the smallest finite-time Lyapunov exponent
George Haller1, Themistoklis Sapsis
1Department of Mechanical Engineering, McGill University, 817 Sherbrooke Ave. West, Montreal, Quebec H3A 2K6, Canada.
Abstract:
We point out that local minimizing curves, or troughs, of the smallest finite-time Lyapunov exponent (FTLE) field computed over a time interval [t(0), t] and graphed over trajectory positions at time t mark attracting Lagrangian coherent structures (LCSs) at t. For two-dimensional area-preserving flows, we conclude that computing the largest forward-time FTLE field by itself is sufficient for locating both repelling LCSs at t(0) and attracting LCSs at t. We illustrate our results on analytic examples, as well as on a two-dimensional experimental velocity field measured near a swimming jellyfish.
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