Variational Methods and Complementary Formulations in Dynamics

Dynamics of Gravitational Waves in 3D: Formulations, Methods, and Tests

The dynamics of gravitational waves is investigated in full 3+1 dimensional numerical relativity, emphasizing the difficulties that one might encounter in numerical evolutions, particularly those arising from non-linearities and gauge degrees of freedom. Using gravitational waves with amplitudes low enough that one has a good understanding of the physics involved, but large enough to enable non...

Variational Methods for Computational Fluid Dynamics

Advantages and Drawbacks of Variational Inequality Formulations

In recent years, the variational inequality framework has been recognized as a powerful modelling tool in operations research and economics, whenever equilibrium relationships among several agents occur. This interest has prompted researchers to develop eecient algorithms for solving variational inequalities in nite dimensional spaces. In this presentation we will try to assess the advantages a...

Solvent effects in time-dependent self-consistent field methods. II. Variational formulations and analytical gradients.

This study describes variational energy expressions and analytical excited state energy gradients for time-dependent self-consistent field methods with polarizable solvent effects. Linear response, vertical excitation, and state-specific solvent models are examined. Enforcing a variational ground state energy expression in the state-specific model is found to reduce it to the vertical excitatio...

Integrable Couplings, Variational Identities and Hamiltonian Formulations

We discuss Hamiltonian formulations for integrable couplings, particularly biand tri-integrable couplings, based on zero curvature equations. The basic tools are the variational identities over non-semisimple Lie algebras consisting of block matrices. Illustrative examples include dark equations and biand tri-integrable couplings of the KdV equation and the AKNS equations, generated from the en...