Hamiltonian optics

Hamiltonian optics and Lagrangian optics are two formulations of geometrical optics which share much of the mathematical formalism with Hamiltonian mechanics and Lagrangian mechanics.

In physics, Hamilton's principle states that the evolution of a system ${\displaystyle \left(q_{1}\left(\sigma \right),\cdots ,q_{N}\left(\sigma \right)\right)}$ described by ${\displaystyle N}$ generalized coordinates between two specified states at two specified parameters σ_A and σ_B is a stationary point (a point where the variation is zero), of the action functional, or

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