Nobel laureates praise prof's superconductivity theory
Chaz Firestone
Issue date: 4/13/07 Section: Campus News
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Cooper, the "C" in the renowned BCS theory of superconductivity, was the keynote speaker in a scientific symposium held Thursday and today to honor the 50th anniversary of his theory's publication. As part of the symposium, six eminent physicists with five Nobel prizes - including three of the last six given in the field - assembled Thursday for a discussion panel and two lectures in Salomon 101.
Though the other Nobel prizewinners do not research superconductivity specifically, the entire two-day symposium is dedicated to BCS theory, which Vesna Mitrovic, assistant professor of physics and a co-organizer of the event, called "the most beautiful and influential theory of the 20th century" - even more so than Einstein's famous theory of relativity.
Superconductivity is a physical phenomenon where current flows through a supercooled metal - or superconductor - without any loss in energy. Normal metals partially impede the flow of electric current and cause some energy to be released as heat. But superconductors, which must be cooled hundreds of degrees below freezing in order to exhibit their special characteristics, allow current to flow unimpeded.
Dutch physicist Heike Kamerlingh Onnes first observed superconductivity in mercury in 1911, but explaining the phenomenon stumped scientists. Even Albert Einstein couldn't establish a theory of superconductivity when he tried in 1922.
"What we had that Einstein didn't was a quantum theory of metals," Cooper said.
Using quantum theory, Cooper came to the conclusion that electrons, which usually repel each other, pair up in a superconducting metal and exhibit a weak attractive force. Now called Cooper pairs, these pairs formed the basis for the BCS theory Cooper developed with colleagues John Bardeen and John Schrieffer.