In a development that has received wide coverage from media outlets ranging from Science to the New York Times, researchers at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory have announced compelling new findings about the properties of matter under conditions similar to those in the early universe. By colliding gold ions at near-light speed at Brookhaven’s Relativistic Heavy Ion Collider (RHIC), physicists have created matter at a temperature of about 4 trillion degrees Celsius--the hottest temperature ever reached in a laboratory.
At these temperatures, which are believed to have existed shortly after the Big Bang, nuclear matter forms a quark-gluon plasma--a state where subatomic quarks and gluons have escaped from the boundaries of the protons and neutrons that normally confine them. In this hot soup, researchers also found “bubbles,” or local regions, that may break important symmetries of nature, including the mirror symmetry (referred to as “parity”) that normally characterizes the interactions of quarks and gluons.
“This research offers significant insight into the fundamental structure of matter and the early universe, highlighting the merits of long-term investment in large-scale, basic research programs at our national laboratories,” said Dr. William F. Brinkman, Director of the DOE Office of Science. “I commend the careful approach RHIC scientists have used to gather detailed evidence for their claim of creating a truly remarkable new form of matter.”
“These data provide the first measurement of the temperature of the quark-gluon plasma at RHIC,” said Dr. Steven Vigdor, Brookhaven’s Associate Laboratory Director for Nuclear and Particle Physics, who oversees the RHIC research program.
Exploring matter and symmetries at these temperatures that mimic the early universe is especially important because of the role broken symmetry may have played in the evolution of the infant universe. The findings may have significant implications for understanding the origin and role of magnetic fields in the early cosmos.
“The announcement of these new results from RHIC, one of four national user facilities operated by the Office of Science of the Department of Energy for basic research in nuclear science, will advance knowledge concerning the force that binds nuclei together and governs the interaction of subatomic particles,” said Dr. Timothy Hallman, DOE Associate Director of Science for Nuclear Physics.
The findings were announced in mid-February at a joint meeting of the American Physical Society and the American Association of Physics Teachers in Washington, DC. The research is detailed in two articles, one that has been published and another that has been accepted for publication in the journal Physical Review Letters.
Further information can be found at Brookhaven National Laboratory’s website at the following links: