Quote:
Originally Posted by r.samanta  well, in my book , momentum of photons is written as h/wavelength and has written that this relation gives particle nature to radiation.
whereas in the chapter atomic phy, it says (p^2/2m+V) zi= E zi where it sounds like an ordinary classical momentum to me.
but blow! in next step it removes p by a derivative!!
i am confused.
and what is canonic momentum? |
I think you're referrring to canonical momentum. The uncertainty principle is the relationship between canonical momentum and position. It is not a relationship between mechanical momentum (i.e. defined by mv) and position. Canonical momentum is a term which comes from analytical mechanics where one uses the principle of stationary action as the starting point. This leads to an important quantity called the Lagrangian. The canonical momentum is defined as the partial derivative of the Lagrangian with respect to a coordinate. The resulting quantity is then called the canonical momentum conjugate to the given coordinate.
If the system is a charged particle moving in an electric field then the canonical momentum is different from mv. This is one thing to be careful about in quantum mechanics, i.e. the difference between mechanical momentum and canonical momentum. Canonical momentum is also called generalized momentum.