Cafe sheds light on dark matter, obscure physics
January 12, 2007
Aspen, CO ColoradoASPEN Want to know about the nature of our universe? Stop in at the Physics Café at the Wheeler Opera House every Wednesday and find out from some of the world’s biggest brains.The Aspen Center for Physics opened the Wheeler Opera House’s doors for the month-long winter lecture series last week. But unless you already know how to manhandle anti-matter or have a firm grasp of the expanding universe, you’ll want to stop in the Wheeler lobby for Aspen Science Center’s Physics Café at 4:15 p.m. Wednesdays for a little background, some understanding – and good cookies.”What I love is that you can ask how big is the universe and get an answer,” said Kevin Ward, director of the science center. He “poaches” from the pre-eminent core of world-class physicists at the Aspen Center for Physics and invites them to the informal sessions. He likes to pair up experimental and theoretical physicists “because they like to disagree with each other.””We wanted a family-friendly, intimate approach to physics,” Ward said, and the weekly café is a chance to get up close, personal and inquisitive with some of the world’s elite physicists.
“We are trying to understand the nature of the universe,” said Florencia Canelli, an Argentinian-born research physicist who works for Fermilab in Chicago. She performs experiments with particle accelerators, takes measurements and seeks particles that existed at the beginning of the universe, running her data through computers the size of buildings. “We put together all of the pieces of the puzzle.””Most people aren’t physicists,” said Neil Miner, a research physicist from New York University who joined Canelli for Wednesday’s Physics Café. He invited the group to ask questions and ask for clarifications that came back in science-speak.”Once you get us started, we just go,” Miner said.Our world is just actually a tiny, tiny fraction of the universe, he told the group. Just 4 percent of the universe consists of the kind of atoms we know. The rest is a mix of dark matter and dark energy, which behave differently. (If regular atoms follow the rules of a baseball game, dark matter and energy are like cricket – it looks the same but has a different mode of operation.)
“How do you know that?” came a shout from the crowd.Miner explained that theorists like himself are busy thinking up these ideas, and researchers like Canelli are testing them in atomic accelerators and collecting data in computers the size of buildings.”Is there dark energy or dark matter in this room?” asked 10-year-old Sam Alexander of Aspen. “Wouldn’t everything be moving apart?”Miner assured Sam there was enough energy holding the atmosphere together to keep us from falling apart. Sam wants to be a physicist or chemical engineer when he grows up, and said he likes the Physics Cafés – especially the cookies.
“If you give kids sugar and bring them to something like this, you keep their attention,” said Frank Alexander, Sam’s father.The Physics Café convenes at 4:15 every Wednesday through Feb. 19 in the second-floor lobby of the Wheeler, followed by a lecture at 5:30 p.m. There is no charge, and refreshments are free. For more information, contact the Aspen Science Center at 309-3390 or visit http://www.aspensciencecenter.com.On Jan. 17, Harvard University’s Charles Marcus will give a lecture on condensed-matter physics after stopping in at the Physics Café.Charles Agar’s e-mail address is email@example.com.