World’s leading cosmologists to assess promising theory of universe at Pritzker Symposium Jan. 29 to Feb. 3 at University of Chicago

Inflation is bad for the economy, but it works wonders for the universe.

The inflation theory proposes that the universe expanded extremely rapidly soon after the big bang and effectively explains a number of important questions that the big bang theory alone as been unable to answer.

Inflation theory also meshes particle physics with astrophysics, inner space with outer space, said Michael Turner, symposium co-chair and Chairman of the University of Chicago’s Astronomy & Astrophysics Department. “It holds that the largest structures in the universe, from galaxies to great walls made of galaxies, originated as quantum fluctuations on the subatomic scale.”

Fourteen of the world’s top experts in cosmology, including Stephen Hawking, will gather Jan. 29 to Feb. 3 for the Pritzker Symposium on the Status of Inflationary Cosmology at the University of Chicago to debate how well inflationary theory holds up against new observations.

The symposium, along with the opening of the new Pritzker Gallery of Cosmology at the Adler Planetarium and Astronomy Museum, marks the official beginning of the city of Chicago’s Project Millennium, a yearlong program to celebrate and reflect upon the millennium. The symposium, the largest meeting ever devoted to inflationary cosmology, is sponsored by the University, Fermi National Accelerator Laboratory and the Adler Planetarium.

“Nicholas Pritzker, an avid cosmologist, approached the Adler Planetarium about a gallery that would trace our understanding of the universe from Copernicus to inflation,” said Evalyn Gates, director of astronomy at Adler Planetarium. “As a result, the Adler created a gallery that even includes pages from the notebook of Alan Guth, one of the inventors of inflation.”

The inflation theory has been around for more than 15 years, but only in the past few years have astronomers collected the first observational data in its support, said symposium co-chair Rocky Kolb, University of Chicago Professor in Astronomy & Astrophysics.

Inflation predicts a pattern of temperature differences in the cosmic microwave background radiation, the big bang’s afterglow. According to the theory, some regions of the sky should have slightly higher temperatures than others, and some should have slightly lower temperatures.

Measurements made by University of Chicago scientists and others are beginning to bear out these predictions, Kolb said.

Inflation also predicts that the total amount of matter and energy in the universe adds up to the critical density, which would mean the universe is flat like a piece of paper instead of curved like a sphere.

“Just this year, we have the first evidence that this is true, and amazingly, that 60 percent of the critical density is in the form of a mysterious dark energy that is causing the expansion of the universe to speed up rather than slow down,” Turner said. “We are excited to have at long last found the ‘missing energy’ that brings the total to the critical density. Now we have to figure out what it is!”

Astronomers are expecting to receive an avalanche of high-quality data during the coming years that will help them to confirm or refute inflation theory and possibly begin to probe the earliest moments of creation, said symposium co-chair Josh Frieman, Fermilab Scientist and Professor in Astronomy & Astrophysics at Chicago.

Crucial to testing inflation is the study of millionth-of-a-degree variations in the temperature of the cosmic microwave background in different directions. Some of the data will come from ongoing experiments on the microwave background radiation conducted at the University’s Center for Astrophysical Research in Antarctica and from balloon experiments at the South Pole involving Chicago scientists.

Further data will come from two satellites: the Microwave Anisotropy Probe that the National Aeronautics and Space Administration will launch in 2000, again with Chicago’s involvement, and the Planck Surveyor, which the European Space Agency will launch in 2007.

The Sloan Digital Sky Survey also will be important in tying down the validity of inflation, according to Kolb. The survey is an international collaboration of scientists and engineers, including Frieman and others at the University, Fermilab and several other universities and laboratories in the United States and Japan, to catalog the positions and brightnesses of more than 100 million galaxies. The survey’s objective is to map one quarter of the sky and create a systematic, three-dimensional picture of the universe 100 times larger than what was previously available.

The NASA and European satellites, on the other hand, will study the large-scale structure of the universe but at a much earlier and simpler time. The cosmic microwave background is, in effect, a snapshot of the universe when it was 300,000 years old, long before stars and galaxies existed.

“We’re hoping in the next few years that these two different maps will complement one another and provide a consistent picture for the large-scale distribution of mass in the universe, and tell us about what conditions were like in the very early universe, thereby testing inflation,” Frieman said.

“Inflation predicts certain patterns of fluctuations in the density of the universe, and that should be imprinted both in the microwave background about 100,000 years after the big bang and also in the large-scale distribution of galaxies, which was laid down more recently.”

The symposium is scheduled for Jan. 29 to 31 and will consist of talks by 14 of the most distinguished cosmologists in the world, summarizing the current status of inflation theory.

Among the astronomers making presentations at the symposium will be the three men who developed the inflation theory: Alan Guth, Massachusetts Institute of Technology; Andrei Linde, Stanford University; and Paul Steinhardt, Princeton University. Also presenting will be two scientists who made fundamental contributions to big bang theory: Sir Martin Rees of Cambridge University and P.J.E. Peebles of Princeton University. Another presenter will be Stephen Hawking, Cambridge University’s Lucasian Professor of Mathematics, a position once held by Isaac Newton.

Hawking will give a public lecture in addition to his scientific presentation to symposium participants. The public lecture, “The Universe in a Nutshell,” will begin at 8 p.m. Jan. 29 in the Arie Crown Theater at McCormick Place. The lecture is sponsored by the Adler Planetarium and the Pritzker Foundation. For ticket information call (312) 559-1212. The public also is invited to visit the newly opened Pritzker Gallery at the Adler Planetarium. For information, call (312) 322-0304.

Following the symposium will be a workshop Feb. 1 to 3 that will be attended by more than 200 experts from around the world.

“I tell my undergraduates at Chicago that every educated person should have some idea of the origin, age and size of the universe,” Kolb said. “We all live in the universe. It’s not just a matter of study for the experts who are coming to this meeting or the few hundred people in the world who call themselves cosmologists. I tell the students, ‘It’s your universe, too.’”

Editor’s Note: Journalists are invited to attend the Pritzker Symposium and Workshop, which will be held in the Max Palevsky Auditorium in Ida Noyes Hall, 1212 E. 59th St., on the University of Chicago campus. To register please contact Steve Koppes at (773) 703-8366. Further information is available at: http://www-astro-theory.fnal.gov/Personal/psw/