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In this issue:
Research Thrives on Jasper Ridge
Science Today: The Danger of Inflation
Drell Elected to AAAS
Touring the Sciences as a Tour Guide

SLAC Today

Thursday - May 3, 2007

Research Thrives on Jasper Ridge

(Photo - Jasper Ridge)
These plastic tubes at one of the field plots of Jasper Ridge's global change experiment help researchers measure carbon uptake.

Less than a mile from the linear accelerator, cormorants, great blue herons, and coots congregate at Searsville Lake, while California quail emerge from coyote brush and red-winged blackbirds sing. Jasper Ridge Biological Preserve is a 1200-acre thriving research site that lies on the south side of the SLAC linac and west of Highway 280.

The area is a living laboratory of plants and animals. The research conducted here is as varied as the preserve's habitats.

"For its size, Jasper Ridge is remarkably diverse," said research coordinator Nona Chiariello. "There are so many plant communities: chaparral, grassland, oak woodland, riparian and serpentine grassland. It's outstanding for both teaching and research."

(Daily Column - Science Today)

The Danger of Inflation

The theory of cosmic inflation has been very successful in explaining the flatness of the universe and the large-scale distribution of matter. This is a part of the beautiful success of the current Standard Models of particle physics and cosmology. Still, we have many reasons to believe that the Standard Model of particle physics is incomplete and to expect that new particles and forces will soon be discovered. Earlier articles on these pages have described models of particle physics beyond the Standard Model based on supersymmetry, extra dimensions, and other marvelous principles. But in all of these theories, we have to worry, like the Federal Reserve, about the danger of inflation. Unlike the economy, though, the danger here is not that the universe will overheat but that it will cool down in the wrong way.

I have been particularly worried about theories with supersymmetry, which I find an attractive route to new models of particle physics. Supersymmetry generalizes the Standard Model by adding a new particle with the opposite statistics for every known particle. We add, then, a fermionic photon (which could be the cosmic dark matter) and bosonic electrons and quarks, which could help to explain the origin of the W and Z boson masses. The theory has many other successes, including a connection to the idea of Grand Unification.

But there is a problem. At high temperature, in the very early universe after the Big Bang, the universe starts in a very symmetrical state. Broken symmetry is needed to give mass to the W and Z and to the quark and leptons. But a supersymmetric model often has many different possible broken symmetry states. During inflation, the universe cools rapidly, and it can easily become stuck in the wrong configuration. This would cause irreparable damage.

Drell Elected to AAAS

SLAC Deputy Director Persis Drell has been named a fellow of the American Academy of Arts and Sciences, a policy research center on emerging international issues. Congratulations to Persis!
Learn more...

Tour the Sciences
as a Tour Guide

Tae Min Hong recently discovered a new way to learn about physics that's almost as effective as graduate school: becoming a SLAC tour guide. "You'd better learn what's going on at SLAC, because people are going to ask you," says Hong, a graduate student from U.C. Santa Barbara who works at BaBar.

Hong has given at least two tours a week since the beginning of this year to visitors ranging from elementary school students to Hewlett-Packard engineers. He says that as a tour guide, he has not only developed his communication skills, but has also increased his enthusiasm for his own research. "When people get excited about what you do, you also get excited about what you do," he says.

Hong says that although he tries to cover all areas of research in his presentation, he focuses mainly on the B physics he studies. "That's why it's important to have more volunteers from other fields, so that they can put emphasis in their expertise."

Interested in leading SLAC tours? Contact tour coordinator Maura Chatwell. All lab employees and users, regardless of their field of study, are encouraged to participate and Chatwell especially seeks guides from the Stanford Synchrotron Radiation Laboratory (SSRL).

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