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Cosmossos
Dec6-09, 06:21 AM
1. The problem statement, all variables and given/known data

Question 3b from the following file:
http://phstudy.technion.ac.il/~wn114101/hw/wn2010_hw07.pdf

I know I need to find a generating function for this spacific transformation. but I don't know how to find it, I mean , how I find a spacific transformation for a spacific hamiltonain?
thnaks

gabbagabbahey
Dec6-09, 03:48 PM
Do you know what the Hamiltonian of a one dimensional harmonic oscillator looks like?

Cosmossos
Dec7-09, 10:07 AM
It's the classic expression (H=p^2/2m+kx^2/2)

gabbagabbahey
Dec10-09, 03:16 PM
It's the classic expression (H=p^2/2m+kx^2/2)

Right, so (using P and Q instead of 'p' and 'x'), you are looking for a canonical transformation Q=Q(q,p) and P=P(q,p), for which [tex]\frac{1}{2}\left(\frac{1}{q^2}+p^2q^4\right)\to \frac{P^2}{2m}+\frac{kQ^2}{2}[/itex] (give or take a constant)...what does the fact that the transformation is canonical tell you?