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A Magnetic Problem with
“Protogalaxies”
Feb
09, 2010
It seems
that it doesn’t matter how far out
in space we choose to observe, there
are galaxies, fully formed galaxies
organized in higher level structures
that stretch for billions of
parsecs.As if
this hasn’t been enough evidence to
undermine the standard model, there
was new information gathered in 2008
that must create even further
misgivings. The issue involves
galactic magnetic fields.
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.
The authors assume this is a
“protogalaxy” simply because of its
distance. However, the relative
strength of the magnetic field (10x)
is interesting. In reading some
source data elsewhere the exact
number is a magnetic field of B = 84
μG in DLA-3C286 (the galaxy in
question) at z =0.692, using the
same Zeeman-splitting technique that
revealed an average value of B = 6
μG in the interstellar gas of the
Milky Way. So, actually the value is
>10x the Milky Way's magnetic field
measurement. In the picture credited
to HW Chen above, it is tempting to
infer that there are prominent jets
emitted by DLA-3C286 consistent with
the magnetic field findings.
"This new measurement indicates that
magnetic fields may play a more
important role in the formation and
evolution of galaxies than we have
realized," said Arthur Wolfe, of the
University of California-San Diego (UCSD).
"Our results present a challenge to
the dynamo model, but they do not
rule it out."
There are other possible
explanations for the strong magnetic
field seen in the one protogalaxy
Wolfe's team studied. "We may be
seeing the field close to the
central region of a massive galaxy,
and we know such fields are stronger
toward the centers of nearby
galaxies. Also, the field we see may
have been amplified by a shock wave
caused by the collision of two
galaxies."
It is clear that observations have
directly contradicted the
mean-field-dynamo model, yet
investigators have trouble letting
go of the theory in the face of
data. The argument about shock waves
and galaxy collision is just
embarrassing and perhaps can be
forgiven in the light of the sheer
usefulness of the data.
In a
New Scientist report the
language is more balanced.
Magnetic fields are difficult to
model, so they tend not to be
incorporated into cosmological
simulations. But if it turns out
more such galaxies are scattered
about the early universe, "it might
mean we have to rewrite all the
models of galaxy evolution because
magnetic fields play a big role",
Beck says.
The quote is from Rainer Beck, not
involved in the research but an
astronomer at the Max-Planck
Institute for Radio Astronomy in
Bonn, Germany. Beck is clearly
allowing the observations to shape
his logical assessment of the
mean-field-dynamo model.
The team next plans to measure the
magnetic field of an even more
distant backlit galaxy - one that
would have had just 1 billion years
or so to spin up its field. If the
galaxy has a similarly strong field,
"I'd say that would be very
difficult for the dynamo theory,"
Wolfe says.
According to the Electric Universe
theory, the observations were
predictable. Galaxies are formed
along immensely powerful Birkeland
currents where magnetic z-pinches
play a critical role in shaping
galaxies and, in turn, the star
systems within them. Therefore, all
galaxies will have magnetic fields
whose strengths will vary depending
on the Birkeland currents that power
them. So the observation of galaxies
6-8 billion light years away with
powerful magnetic fields is
completely in keeping with the
Electric Universe model, because
magnetic fields are integral to
galaxy formation and their ongoing
dynamics.
This research should be closely
monitored, but the EU model makes a
clear prediction. Wolfe and his
colleagues will find a magnetic
field spanning the next galaxy they
directly measure with the Zeeman
effect. Galaxies do not “spin up”
magnetic fields, it’s the other way
around.
As long as astronomers and
astrophysicists continue with a
conceptual framework that does not
include electrical forces acting at
the cosmological scale, they will
continue to be surprised by their
observations. Ultimately, the really
interesting phenomenon to observe in
all this is the human ability to
cling to belief systems in the face
of overwhelming data. The Electric
Universe movement is an exciting
opportunity to witness a single
explanatory framework driving
paradigm shifts across multiple
disciplines.
Contributed by Thomas Wilson
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