0

Peston defines $B(T_\lambda;I_1\rightarrow I_2)$ by averaging over the initial magnetic $m$ states of $I_1$and summing over the final magnetic states of $I_2$. How can one show that this does not mean that a single initial magnetic subtate can cause transition to the many fimal magnetic substate at the sane time. I know this can be answered but I am looking for a good answer.

SAKhan
  • 1,365

1 Answers1

0

It is not obvious to me that a single initial magnetic substate cannot transition to a superposition of many final magnetic substates. So I am not sure anyone can show what you want.

akhmeteli
  • 26,888
  • 2
  • 27
  • 65
  • Why not take the average over final states – SAKhan Jan 02 '19 at 05:20
  • And of course the initial state can also be a superposition so why not take the sum according to your answer. – SAKhan Jan 02 '19 at 06:32
  • @SAKhan : it was discussed elsewhere (https://physics.stackexchange.com/questions/137188/why-in-spin-sums-we-sum-over-final-spin-states-and-average-over-initial-states) – akhmeteli Jan 02 '19 at 07:46