New posts in Lagrangian Formalism

Generalised coordinates

Equivalence of two Lagrangians

Do generalized coordinates have to be orthogonal?

Are all Lagrangians translationally invariant?

Does a Lagrangian always generate a unique Hamiltonian?

Does the quadratic mass term $\frac{1}{2}m^2\phi^2$ belong to the free Lagrangian or is it an interaction term?

Why does a square root term make the quantisation of action difficult?

Why can we shift the field $\phi$, so that $\langle \Omega | \phi(x) | \Omega \rangle = 0$?

Why is this a non-holonomic constraint?

Is there a deep reason why action comes from a local lagrangian?