primordial soup

Expansive solution

Primordial soup: quark-gluon plasma created by the collision of heavy atomic nuclei

CERNPrimordial soup: quark-gluon plasma created by the collision of heavy atomic nucleiCERN

Theoretical physicists have discovered the first mathematical solution to precisely describe the expansion of one drop of quark-gluon plasma. Called cosmic primordial soup, the quark-gluon plasma is the state attained by the materials when the protons and neutrons in atomic nuclei dissolve in a liquid 250,000 times hotter that the sun (see Pesquisa FAPESP Issue no. 213) The plasma is created in small quantities when heavy atomic nuclei collide in the large particle accelerators like the Large Hadron Collider (LHC) in Europe and the Relativistic Heavy Ion Collider (RHIC) in the United States. The properties of a drop of plasma in expansion, however, can only be approximated in computer simulations. “These calculations are complex, and there is no way to guarantee the accuracy of the results,” explains Jorge Noronha, a physicist at the University of São Paulo who solved the problem in partnership with Brazilian Gabriel Denicol at McGill University, and colleagues at other North American institutions. The physicists can now use the solution described in the November 2014 issue of Physical Review Letters to verify if the detailed calculations done by the computer are correct. “Our solution has become a standard test,” says Noronha.