Existence of standard map parameters with nonnegative Lyapunov exponent
Determine whether there exist values of the parameter in the standard map for which the Lyapunov exponent is nonnegative.
References
Many basic questions, such as the existence of any values of the parameter of the standard map for which the Lyapunov exponent is nonnegative, are famous and difficult open problems in the theory of differentiable dynamical systems.
                — Computational Dynamical Systems
                
                (2409.12179 - Cotler et al., 18 Sep 2024) in Section 2.1 (Overview of dynamical systems) – Fundamental examples, item 7