# Index

- Physics 427 in Winter Quarter 2008. A seminar
course on Modern Physics and the Modern World. This was an exploration of
which discoveries in Physics during the past seventy five years or so have
had an important impact on how we live or on other sciences outside
Physics. The time period is chosen to exclude the revolutionary period in
which quantum theory, the atomic nucleus, and relativity theory were
discovered.

2001 paper with Vinen, Geller, Fortin and
Rhee on the transverse force on a quantized vortex due to its motion
relative to the normal fluid. Work that we (Ping Ao, Qian Niu, and
myself) did in 1996 gave results in conflict with long generally accepted
results obtained by Iordanskii in the 1960s. We made a careful
examination of this problem, and found how how two-fluid dynamics changes
the results wich Iordanskii obtained.

2007 paper with James Anglin on the mass of a
quantized vortex. The literature on quantized vortices contains
statements by very respectable authors either that the mass density of a
quantized vortex is infinite, or that it is negligible. We developed a
clearer method for examining this problem. We found that the mass goes
have an infrared divergence

2005 paper with Ping Ao and Chulan Kwon on the
structure of stochastic dynamics near fixed points. This paper gives a
new way of dealing with problems in which there is no detailed
balance, and so the usual methods of statistical mechanics cannpot be
used. Ping Ao has published papers in which the method is applied to
problems such as the transition between latency and activity of
bacteriophage, the spread of cancer cells, and evolutonary theory.