Quantum Mechanics @ UNM

Problem Set 12 will be our last problem set for the semester, and will be due on the last day of class.  It will have three problems: one of them will be moderately long, and the other two will be pretty short, once you figure out what to do.I will post the problem set today.  I’ll be at problem session in case anyone has any lingering questions from the semester, or needs help with an older problem set.  But, otherwise we will have our last problem session a week from today to work on the last homework.It’s getting really close to the end!PROBLEM SET 12 UPDATE: Problem 1 should read “Compute the second order correction to the energy eigenkets for situations where the first order energy correction vanishes.”  This last part of the sentence is important to get the stated result. 

I think I found two minor typos. In equation (5), the third term ket should I think be | down up down >, since the last two states are always opposite. Also in (10), I think the third term should end in |down>_B rather than |up>_B.

Hey there all you grad school visiting people- just wanted to let you know that we did not get through all the material in the lecture notes for Thursday.  We finished discussing why a ket cannot be used to describe the state of a spin-1/2 particle following a Stern-Gerlach experiment where you ignore the measurement result.   But, we did not get all the way to formulating the density operator— we’ll pick up with doing so on Tuesday morning and hopefully also manage to derive thermal states in the same day.  It will be action-packed. 

Unfortunately, I will not be able to lecture on Tuesday.  So, we will get started back up on Thursday and then see if we need to have a make-up lecture some time later down the road. Problem Set 8 has been posted.  It will be due a week from Tuesday. 

I’m sure you will all be happy to know that I have officially removed problem (1.10) from problem set 7.  Yay.  DOWNLOAD THE LATEST VERSION NOW