January 2, 2013
Magnetic Fields Created Before Stars In The Early Universe
Lee Rannals for redOrbit.com — Your Universe Online
An astronomer wrote in the journal Physical Review Letters about a new mechanism for the magnetization of the early universe.
Before stars formed, luminous matter consisted only of fully ionized gas of protons, electrons, helium nuclei and lithium nuclei which were produced during the Big Bang.
“All higher metals, for example, magnetic iron could, according to today´s conception, only be formed in the inside of stars," Dr. Reinhard Schlickeiser, of the Institute of Theoretical Physics of the Ruhr-UniversitÃ¤t Bochum, said in a statement. “In early times therefore, there were no permanent magnets in the Universe."
The parameters that describe the state of a gas are not constant. Density and pressure, as well as electric and magnetic fields fluctuate, and are known as random fields. Schlickeiser helped to calculate how strong these fields are in a fully ionized plasma of protons and electrons.
He found that magnetic fields fluctuate depending on their position in the plasma, regardless of time. Electromagnetic waves such as light waves fluctuate over time.
Throughout the early universe, there was a magnetic field with a strength of 10 sextillionth of a Tesla. By comparison, the earth's magnetic field has a strength of 30 millionths of a Tesla. MRI scanners have field strengths of only three Tesla.
The magnetic field in the plasma of the early universe was very weak, but covered almost 100 percent of the plasma volume.
Stellar winds or supernova explosions of the first massive stars generated sick waves that compressed the magnetic random fields in certain areas. The fields were strengthened and aligned on a wide-scale, and ultimately the magnetic force was so strong it influenced the shock waves.
“This explains the balance often observed between magnetic forces and thermal gas pressure in cosmic objects," Schlickeiser said.
Calculations show that all fully ionized gases in the early universe were weakly magnetized. Magnetic fields existed even before the first stars.
Schlickeiser hopes to examine how the weak magnetic fields affect temperature fluctuations in the cosmic background radiation for his next research project.