The paper will consist of a critical discussion of either some physical phenomenon or of an invention important to humanity which depends on the principles of physics in a non-trivial way. The paper should show how such a phenomenon or device works. A draft version of your paper will be peer-reviewed by your classmates. I expect of order 10 typewritten double-spaced pages. References should be made to material used to construct the paper and should be given in some standard form – I don't care which. However, at least three references for this paper should be “library” as opposed to WWW references.