Hamilton–Jacobi equation

A first-order partial differential equation whose solution S, Hamilton's principal function, describes the motion of a classical system through its generalized coordinates and time. It is used to find trajectories in classical mechanics and to connect mechanics with wave optics and quantum theory.

-\frac{\partial S}{\partial t} = H\left(\boldsymbol{q}, \frac{\partial S}{\partial \boldsymbol{q}}, t\right)

What the symbols mean

Hamilton's principal function (action as a function of coordinates and time), in joule-seconds
time, in seconds
vector of generalized coordinates
Hamiltonian function of the system, in joules

About this formula

  • FieldPhysics
  • TopicClassical mechanics
  • LevelAdvanced
  • Also calledHJE, HJ equation, Hamilton Jacobi equation, principal function equation, classical mechanics partial differential equation, Hamilton principal function PDE
  • SourceWikidata Q1060137

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