Paul Alivisatos, Cornell's fall 2011 Bethe lecturer, explained the science behind the evidence that human activity is causing global warming, September 28, 2011. Alivisatos is director of Lawrence Berkeley National Laboratory.
The Bethe Lectures honor Hans A. Bethe, Cornell professor of physics from 1936 until his death in 2005. Bethe won the Nobel Prize in physics in 1967 for his description of nuclear processes that power the sun.