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Scientist rocks out and explains string theory, all at once

This article first appeared in the St. Louis Beacon: October 12, 2008 - Mark Lewney, Ph.D. and celebrity science presenter, greeted those taking their seats at his SciFest presentation Friday with fully amplified rock guitar licks.

But this was more than a rock concert. In an entertaining, fast-moving presentation, Lewney (pronounced loony) took his audience from listening to the electric guitar in all its versatility to an explanation of how guitar strings create their particular sounds. Explaining that a string anchored at each end has a fundamental vibration dependent upon its length, tension and thickness, he then showed how harmonics are created.

In full heavy metal demo mode -- meaning many decibels -- he showed how electric guitars use their amplifiers to create electronic harmonics imposed upon their natural harmonics. Thus, physics explained the difference in sound between acoustic and electric guitars.

Once he got the audience thinking about vibrating strings, Lewney moved rapidly into string theory, asking at one point if it could be true that the universe is made of music.

To demonstrate aspects of these complex theories, Lewney used a succession of lively demonstrations from parlor magic tricks to being pelted with about 50 little balls thrown by children in the audience. He ended by describing what might come from experiments in the new European supercollider -- particles that might fit into some string theory, or some particles that might be candidates for the constituents of dark matter.

Lewney suggested that the supercollider scientists might find some tiny black holes that would allow gravity to leak in from other dimensions. Madeline L'Engle fans had no trouble with that concept.

And black holes, by the way, are victims of bad press. Only material very close to black holes gets sucked into them. If the sun collapsed today to become a black hole, only material within a 3 km radius would disappear. Earth would be very, very cold, but would stay put in the galaxy. As Lewney explained, “Simply put, black holes are called that because space-time has been warped so light can’t escape.”

String Theory explained

String theory, sometimes called the "theory of everything," refers to mathematical models in which the universe is made of tiny vibrating strings of energy on the order of 10-35 meters (atoms are about 10-10 meters). These minuscule strings theoretically vibrate at different frequencies to make all the elementary particles that compose the universe. And somehow, the mathematics of string theory can require up to 11 dimensions.

Lewney carefully made clear that string theory is a mathematical concept, and no one has yet been able to test the theory experimentally. The beauty of the theory is that if true it would explain some of the questions puzzling today's physicists.

Part of the fun came from Lewney's delivery of high energy patter in the accent of his native Liverpool. He is a natural showman. Since he entered and won the first FameLab, "the American Idol for Scientists," at the 2005 Cheltenham Science Festival in England, he has become a science celebrity. He has been described as "a cross between Einstein and Jimi Hendrix."

Jo Seltzer is a freelance writer with more than 30 years on the research faculty at the Washington University School of Medicine and seven years teaching technical writing at WU's engineering school. 

Jo Seltzer