Use a neural network to predict only constitutive exchange coefficients, while a fixed skew-symmetric operator generates the conservative part of the update and a structured thermodynamic operator generates the irreversible source. The resulting layer preserves a chosen energy exactly in continuous time and can enforce nonnegative entropy production through a constrained parameterization of exchange rates.
Paper: Data driven non-equilibrium moist phase exchanges for atmospheric convection within a discontinuous Galerkin model of the compressible Euler equationsarXiv:2607.13360
Replace an unconstrained one-step transition network with a symmetric damping–symplectic-core–damping composition. The damping strength is one learned scalar rate and is applied through positive exponential diagonal factors, so every step has a known contraction law while the neural core models nonlinear conservative transport.
Replace several fixed message-passing layers with an implicit graph layer whose state is the solution of a nonlinear flow equilibrium. Learn monotone edge laws from endpoint features, solve for node potentials with damped chord-Newton steps, and use the resulting edge flows or potentials as the layer output. Monotonicity and the Laplacian Jacobian provide a principled stability mechanism while retaining sparse graph computation.