List of variational topics

• Action
• Averaged Lagrangian
• Brachistochrone curve
• Calculus of variations
• Catenoid
• Cycloid
• Dirichlet principle
• Euler–Lagrange equation cf. Action
• Fermat's principle
• Functional
• Functional derivative
• Functional integral
• Geodesic
• Isoperimetry
• Lagrangian
• Lagrangian mechanics
• Legendre transformation
• Luke's variational principle
• Minimal surface
• Morse theory
• Noether's theorem
• Path integral formulation
• Plateau's problem
• Prime geodesic
• Principle of least action
• Soap bubble
• Soap film
• Tautochrone curve