Thomas Wilson: A Magnetic Problem with “Protogalaxies”.
The accepted "mean-field-dynamo" theory held by establishment astronomers asserts that a magnetic field in a galaxy evolves from a “magnetic seed” and builds over the course of billions of years. Young galaxies have no coherent magnetic fields, but over time, a magnetic field “spins up” that spans the galaxy. The mechanism by which this occurs is not well formulated. However, this model predicts that galaxies observed at sufficient distances should have weak magnetic fields compared to our own galaxy.
This assumes a Universe that is about 13.7 billion years old, so that if we look at galaxies 6 to 8 billion light years away, they are comparatively young. Over the course of 2008 there were two separate reports (one in July, the other in early October) of galaxies 6-8 billion light years away with magnetic fields at least as powerful as that found in our own galaxy. In one report, the magnetic field in the distant “young” galaxy was about ten times the strength of that in the Milky Way. As usual, the reporting scientists expressed surprise at their findings.
The research teams actually used different approaches for measuring the magnetic field strength in the different galaxies. Simon Lilly’s group reporting in July performed analyses on a number of galaxies using Faraday Rotation data derived from the polarization of light from quasars behind the galaxies in question. Lilly used FR quasar measurements generated by Philipp Kronberg from the University of Toronto.
Alternatively, the group led by Arthur Wolfe measured the magnetic field in a single galaxy using the Zeeman Effect, where an absorbing gas in a magnetic field splits absorption lines symmetrically.
Some of Wolfe’s comments are interesting and indicative of a general mindset in the astronomical community. Here are excerpts from the October report:
"Astronomers have made the first direct measurement of the magnetic field in a young, distant galaxy, and the result is a big surprise.
Looking at a faraway protogalaxy seen as it was 6.5 billion years ago, the scientists measured a magnetic field at least 10 times stronger than that of our own Milky Way. They had expected just the opposite.
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