The Princeton University website has some great lectures in its WebMedia archive on their website. Notably, the three part Search for a Fundamental Reality by Nobel prize physicist David Gross, and Antonio Damasio’s Advances on the Neurobiology of Emotion, which I had the pleasure of attending. Recent lectures include David Mermin’s Spooky Actions at a Distance? and Hendrik Lenstra’s Escher and the Droste Effect. Of particular interest to fellow locals: Kenneth Jackson’s If All the World Were New Jersey: The Past and Future of the Garden State. The archive has dozens of lectures from the last decade, on a wide range of topics, including physics, cognitive science, philosophy, and politics, most in both RealMedia and WindowsMedia, high and low resolution.

WebMedia Archive, Princeton.edu

Ok, I’ve mentioned before how MIT has this OpenCourseWare program, whose goal it is "to make the courses materials that are used in the teaching of almost all the undergraduate and graduate subjects taught at MIT available on the Web, free of charge, to any user, anywhere in the world." Well, now they have video and audio files of lectures for a number of courses, including:

Animal Behavior
Electromagnetics and Applications
Nano-to-Macro Transport Processes

More audio/visual courses at MIT OpenCourseWare

David Gross, physics professor at UC-Santa Barbara and 2004 Novel Prize laureate for the discovery of asymptotic freedom, is giving a series of public lectures this week entitled "The Search for a Theory of Fundamental Reality." Taking place April 25-27 in the Helm Auditorium, McCosh 50, at 8pm, the series break-down is:

"Theory of Elementary Particles" on Tuesday
"Questions and Speculations: The Search for a Unified Theory" on Wednesday
"The Coming Revolutions: Toward a New Understanding of Space and Time" on Thursday

Also of interest, though in a competing time-slot, there is a computational mathematics lecture "Quantum Computers: How Physics Experiments Might Solve Mathematical Problems" by Peter Shor of MIT, at 8pm in A02 McDonnell.

Princeton Calendar of Events

Physicists currently estimate that only 4% of the universe is made up of baryonic matter, which we can detect and measure with our current senses and instruments. So, 96% of what makes up the universe is in a form that has never been observed directly in a laboratory: 73%t is believed to be dark energy and 23% dark matter. Dark matter cannot be seen because it emits no light. It was hypothesized 50 years ago to explain why the outer limits of a galaxy travel at the same speed as the dense center. With so much of the ‘verse still invisible to us, a unified Theory of Everything may be further away than we’d hoped.

The darkness inside of everything, TheAge.com.au

A team of researchers from the Ecole Polytechnique Federale de Lausanne (EPFL) has successfully demonstrated, for the first time, that it is possible to control the speed of light - both slowing it down and speeding it up - in an optical fiber, using off-the-shelf instrumentation in normal environmental conditions. Their results, to be published in the August 22 issue of Applied Physics Letters, could have implications that range from optical computing to the fiber-optic telecommunications industry.

Using their Stimulated Brillouin Scattering (SBS) method, the group was able to slow a light signal down by a factor of 3.6, creating a sort of temporary “optical memory.” They were also able to create extreme conditions in which the light signal travelled faster than 300 million meters a second. And even though this seems to violate all sorts of cherished physical assumptions, Einstein needn’t move over - relativity isn’t called into question, because only a portion of the signal is affected.

Abstract: We demonstrate a method to achieve an extremely wide and flexible external control of the group velocity of signals as they propagate along an optical fiber. This control is achieved by means of the gain and loss mechanisms of stimulated Brillouin scattering in the fiber itself. Our experiments show that group velocities below 71 000 km/s on one hand, well exceeding the speed of light in vacuum on the other hand and even negative group velocities can readily be obtained with a simple benchtop experimental setup. We believe that the fact that slow and fast light can be achieved in a standard single-mode fiber, in normal environmental conditions and using off-the-shelf instrumentation, is very promising for a future use in real applications.

Light that travels… faster than light! ScienceBlog.com
Optically controlled slow and fast light in optical fibers using SBS, Miguel Gonzalez-Herraez, Kwang-Yong Song, and Luc Thevenaz