Deciding when a given metric is Hessian via reparameterization and potential function
Develop a method to determine, given a Riemannian metric g expressed in a parameterization λ on a single global chart, whether there exists a reparameterization θ and a convex potential function F(θ) such that g(θ)=∇^2F(θ), thereby deciding whether g is a Hessian metric.
References
Finally, let us list some open problems: Problem 3. Given a Riemannian metric $g$ expressed using parameterization $\lambda$ (i.e., given $g(\lambda)$ on a single global chart), how to find, if possible, a parameterization $\theta$ and a potential convex function $F(\theta)$ such that $g(\theta)=\nabla2 F(\theta)$ (i.e., check whether the geometric metric $g$ is Hessian or not).
— Approximation and bounding techniques for the Fisher-Rao distances between parametric statistical models
(2403.10089 - Nielsen, 15 Mar 2024) in Conclusion: Summary and some open problems (final section)