Hey thanks. Does that mean it is meaningless to define the lagrangian of a system without referring to rest of the universe. We actually do it all the time by considering isolated systems and then deriving lagrangian by consideration of symmentries. In fact lagrangian of a two particle is...
Hello
I am using Landau's mechanics Vol I for classical mechanics. On page 4 he mentions for Lagrangian of a system composed of two systems A and B which are so far away so that their interactions can be neglected.
then for the combined system we have L = LA + LB
I'm trying to...