The good thing is that the least action principle is fundamental and very flexible. All the physics are encapsulated in the Lagrangian. So you can come up with

The good thing is that the least action principle is fundamental and very flexible. All the physics are encapsulated in the Lagrangian. So you can come up with any crazy Lagrangian you want, plug it into Hamilton’s principle or Euler-Lagrange equations and see what you get. That way, you can build a whole theory from an insight somewhat easily as the fundamental framework is already in place.