2 problems

Let $J^\infty(\widehat M)$ be the infinite jet space, and let $\overline{\mathcal E}^k$ denote the space of differential forms of degree $k$ in the extended variational complex. Th…

Let $M$ be a smooth manifold equipped with a bihamiltonian structure $(P_0,P_1)$ of hydrodynamic type. The bihamiltonian cohomology group is denoted by…