Classical 2p. Somtmes it is llustrative to consider some aspects of a quantum system the radius...
Exercise 17.3.4.* We discuss here some tricks for evaluating the expectation values of certain operators in the eigenstates of hydrogen. (1) Suppose we want (1/ r m. Consider first (2/r). We can interpret ( r) as the first- order correction due to a perturbation 1/r. Now this problem can be solved exactly; we just replace e? by e- 2 everywhere. (Why?) So the exact energy, from Eq. (13.1.16) is E(X) = -(e-2) m/2n'h. The first-order correction is the term linear...