2025/05/28 by Hu, Yuhao
#35L10 #53C10 #58A15 #Analysis of PDEs (math.AP) #Differential Geometry (math.DG) #FOS: Mathematics
paper · doi:10.48550/arxiv.2505.21998
For hyperbolic Monge-Ampère systems, a well-known solution of the equivalence problem yields two invariant tensors, S1 and S2, defined on the underlying 5-manifold, where S2=0 characterizes systems that are Euler-Lagrange. In this article, we consider the `opposite' case, S1 = 0, and show that the local generality of such systems is `2 arbitrary functions of 3 variables'. In addition, we classify all S1=0 systems with cohomogeneity at most one, which turn out to be linear up to contact transformations.