lagrangian_formalism

`Least action principle`

The Lagrangian formalism is a universal approach to describe the evolution of a physical system. The basic idea is the least action principle, the idea that the evolution minimizes some quantity (for example the energy).

The resulting equations are called the *Euler-Lagrange equations*. This formalism can be applied to all known physical theories, such as classical mechanics, general relativity or quantum field theory.

A nice explanation in three steps (intuitive, example, abstract) can be found here:

- The Physics Travel Guide, Lagrangian formalism

- Hamiltonian formalism
- Euler-Lagrange equation

lagrangian_formalism.txt · Last modified: 2021/09/13 12:29 by alex_th