Wayne State Prof Aids Study Of Early Universe
A Wayne State University researcher has devised a groundbreaking measurement technique that could vastly improve physicists' understanding of the first microsecond of the Big Bang and provide insight to fundamental questions about the universe.
Sergei Voloshin, professor of physics and astronomy in WSU's College of Liberal Arts and Sciences, successfully performed a measurement indicative of violations of mirror symmetry during conditions similar to that of the early universe at the U.S. Department of Energy's Brookhaven National Laboratory. The results were published in the December 14, 2009, edition of Physical Review Letters and May 28, 2010, edition of Physical Review C.
If verified, the observation may lead to answers to some of the major questions in physics, such as the reason the universe is composed of matter rather than antimatter and the mechanism that generates the masses of protons and neutrons.
The discovery stems from Voloshin's work as a member of the BNL's STAR Collaboration, which conducts experiments using the Relativistic Heavy Ion Collider, a 2.4-mile-circumference "atom smasher" track at the BNL. Since 2000, an international team of physicists has been conducting collisions of heavy gold and copper ions and protons as a means to investigate the basic structure and fundamental forces of matter. Among the goals of RHIC is to understand conditions that occurred in the first microseconds after the Big Bang, when high-speed, high-temperature collisions determined the nature of the universe as we know it.
At this year's annual meeting of the American Physical Society in Washington, D.C., the RHIC announced milestones that expand on the 2005 discovery of a "hot soup" of quarks (fundamental elements of matter) and gluons (expressions of quark interactions) present in the universe's first moments. From an experiment that involved colliding gold ions together at nearly the speed of light, researchers were able to create matter at a temperature of an estimated 4 trillion degrees Celsius, about 250,000 times hotter than the center of the sun. This temperature, based on measurements by the PHENIX collaboration at RHIC, is hot enough to melt protons and neutrons into a soup of their constituent parts -- conditions similar to the first microsecond after the Big Bang.
Using a technique he developed at Wayne State, Voloshin successfully obtained the first evidence for the violation of mirror symmetry, which normally characterizes the interactions of quarks and gluons. If confirmed by other experiments, this discovery may help scientists understand a similar violation of symmetry in the early universe that resulted in the predominance of matter over antimatter and other fundamental questions in physics.
"Symmetries are the cornerstone of all physics theories," Voloshin said. "They govern the laws of physics and determine the form of mathematical description. A better understanding of these symmetries -- and the degree by which symmetry is broken -- would expand our knowledge of how the universe works."
The team of nuclear physicists at Wayne State who are members of the RHIC's STAR Collaboration includes Rene Bellwied, Thomas Cormier, and Claude Pruneau, professors of physics and astronomy. The team members also are collaborators in ALICE (A Large Ion Collider Experiment), one of the six detector experiments being constructed at the Large Hadron Collider at CERN, the European Organization for Nuclear Research.
"Professor Voloshin's work has opened new possibilities in the international effort to understand how the universe began," said Ratna Naik, professor and chair of physics and astronomy at WSU. "I look forward to his future studies at Wayne State, where he and the other members of the team working in the STAR Collaboration have brought the university to the forefront of RHIC physics research."
(c) 2010, WWJ Newsradio 950. All rights reserved.