\documentclass[10pt]{article} \usepackage{graphicx, multicol,wrapfig,exscale,epsfig,fancybox,fullpage} \pagestyle{empty} \parindent=0pt \parskip=.1in \newcommand\hs{\hspace{6pt}} \begin{document} \centerline{\bf Quantum Calculations on a Ring IV} \bigskip Consider the following normalized abstract quantum state on a ring: $$\vert \Phi\rangle=\sqrt{2\over 3}\vert -3\rangle+ {1 \over \sqrt{6}}\vert -1\rangle+{i \over \sqrt{6}}\vert 3\rangle$$ \begin{enumerate} \item What is the expectation value of $\hat{L}_z$ as a function of time for this state? \vfill \item What is the expectation value of the energy as a function of time for this state? \vfill \end{enumerate} \vfill \leftline{\it by Corinne Manogue, Kerry Browne, Liz Gire, Mary Bridget Kustusch, David McIntyre} \leftline{\copyright 2012 Corinne A. Manogue} \end{document}