A new experiment shows that a relatively simple system that's not initially magnetized can generate magnetic fields out of nothing, said University of Michigan astrophysicist Paul Drake.
"From the standard theories of the Big Bang, you don't start with a strong magnetic field. It has to arise out of what the universe does," Drake told Discovery News.
Working in a laboratory in France, scientists fired high-energy lasers that pulse in a billionth of a second with a trillion times the intensity of sunlight into a helium-filled chamber. The lasers are made of carbon rods, similar to what is found in ordinary pencil lead.
When they pulse, some of the carbon atoms are ripped apart and explode, creating a blast wave that moves out into the gas and generates a magnetic field.
The process is similar to what happens when a star explodes. It shows one mechanism by which the universe formed and evolved.
Gravity gets the process started, eventually giving rise to collapsing objects that send out shock waves.
"Shocks are the driving force for the formation of magnetic field, and all this precedes galaxy formation," lead researcher Gianluca Gregori, with Oxford University in the United Kingdom, told Discovery News.
Once magnetic fields are established, turbulence takes over, making them larger and sustaining them over the eons.
"It's been rather mysterious that the universe is as magnetized as it," Drake said. "When you do simple calculations, any magnetic field formed in the early phases of the universe one would think should have vanished by now."
Magnetic fields are found everywhere in the universe, even in places where they seemingly shouldn't exist, such as the voids between clusters of galaxies.
Read more at Discovery News
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