Cosmic Magnetism Revealed!

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Well, almost.

Magnetism is one of the four fundamental forces. But there has been little to no discussion about its role in the evolution of the Universe. How did Magnetic Fields originate? What role do they play in the evolution of the first stars and galaxies? Does magnetism look and behave the same way in the early Universe as they do now? How strong are these fields throughout interstellar space? And are they affecting galaxies at cosmological scales? The fact that “Cosmic Magnetism” is one of the five key science drivers for the Square Kilometer Array, the biggest project ever proposed for radio astronomy.

According to Mr. Kandaswamy Subramanian of the Center for Astronomy and Astrophysics in India, magnetic fields are crucial for understanding a number of physical processes in the universe. "They give fluid-like properties to plasma and affect transport properties like thermal conduction, viscosity and resistivity of plasmas," he says.

Modern-day star-formation is governed by magnetic fields, perhaps even controlling the typical mass for average stars. Magnetic fields also rule the way matter is ejected away from the cores of active galactic nuclei, and magnetic fields around galaxies affect the way cosmic rays travel across the universe.

The evolution of magnetic fields is characterized by an "induction equation" that Subramanian presents in his paper, "Magnetizing the Universe," published in the Proceedings of Science (http://pos.sissa.it/) following a scientific conference in October 2007. He explains that it is a combination of Maxwell equations and a simple form of Ohms Law. He summarizes the current field of understanding and identifies the gaps scientists will need to fill before they will be able to fully form a coherent theory of the evolution of magnetism in the universe.

Fortunately for scientists, the Square Kilometer Array is in development and will help explain the origin of cosmic magnetism. It remains one of the most fascinating questions in modern physics.