Web Watch

To suggest topics or sites for Web Watch, please visit http://www.physicstoday.org/suggestwebwatch.html . Compiled and edited by Charles Day

http://www.edge.org/documents/archive/edge145.html

Since 1996, the online magazine The Edge has covered developments in science and society. In a recent issue, two physicists, Lee Smolin of the Perimeter Institute and Len Susskind of Stanford University, debate the merits of the anthropic principle. The debate, Smolin vs. Susskind: The Anthropic Principle, takes the form of an e-mail exchange followed by closing arguments.

http://geomag.usgs.gov

The National Geomagnetism Program of the US Geological Survey provides calibration, measurement, and other services to clients in government, academia, and business. But it also offers the general public a host of educational resources about Earth’s magnetic field, including movies of how the field fluctuates.

http://www.physics.colostate.edu/hadley_html

For reassurance that Earth is indeed rotating, you can watch the precession of the Foucault pendulum installed in the physics department at Colorado State University. Named in honor of CSU physicist Lawrence Hadley, the Hadley Pendulum has an oscillation period of 5 seconds and precesses at about 10° per hour. Three webcams observe its progress.