Classical and Continuum Physics Differential Equations Differential equations Elastic materials Elasticidad Elasticity Élasticité General Geometric optics Hyperbolic equations and systems [See also 58J45] Mathematical models Mechanics of deformable solids Modelos matemáticos Modèles mathématiques Nonlinear elasticity Nonlinear second-order hyperbolic equations Numerical Analysis Numerical analysis Optics, electromagnetic theory {For quantum optics, see 81V80} Partial differential equations Physics