Flux-variational formulation of relativistic perfect fluids

We give a variational formulation of perfect fluids on a general pseudoriemannian manifold by variating tangent fields according the flux produced by them. In fact, in this approach the key point is to consider those variations that preserve the canonical structure of the bundle of fluxes (see below). As a result, Euler and continuity equations are obtained quite directly. (C) 2019 Elsevier B.V. All rights reserved.