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proto-stars would form as subvortexes. However, it will be a long time yet
before man-made probes are able to venture out into the galactic disk with
instruments to test such theories.
Peratt's Models and Simulations: Galaxies in the Laboratory
Encouragement came, nevertheless, from a different direction. In 1979, Anthony
Peratt, who had been a graduate student of Alfvén's ten years previously, was
working with the aerospace defense contractor Maxwell Laboratories on a device
called Blackjack V, which generated enormous pulses of electrical power 10
trillion watts! to vaporize wires into filaments of plasma, producing intense
bursts of X rays. The purpose was to simulate the effects of the
electromagnetic pulse produced by a hydrogen bomb on electronics and other
equipment. High-speed photographs showed the filaments of plasma moving toward
each other under the attraction of their magnetic fields, and then wrapping
around each other in tight spiral forms strikingly suggestive of familiar
astronomical pictures of galaxies. Computer simulations of plasma interactions
that Peratt performed later at the Los Alamos National Laboratory duplicated
with uncanny faithfulness the features of all known galaxy types. By varying
the parameters of the simulations, Peratt was able to match the result with
every one of the pictures shown in Halton Arp's
Atlas of Peculiar Galaxies and guess with confidence just what electromagnetic
forces were shaping the galaxies.
These simulations also suggested a possible answer to another mystery that
astronomers had been debating for a long time. In a galaxy held together
purely by gravity, the velocity of the component stars about the center as it
rotates should decrease with distance from it as with the Solar System, in
which the outer planets move more slowly in their orbits around the Sun.
Observations, however, show that the speeds of stars orbiting the galactic
center remain fairly constant regardless of distance. This is just what the
simulations showed would be expected of an electrically formed galaxy, where
the spiral arms form coherent structures that trail back like the cords of a
gigantic Weed Eater, moving with the same velocity along their whole length.
Conventional theory had been forced to postulate an invisible halo of the
strange gravitating but otherwise noninteracting dark matter surrounding a
galaxy there for no other
reason than to produce the desired effect. But with electromagnetic forces,
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behaving not peculiarly but in just the way they are observed to on Earth, the
effect emerges naturally.
An Explanation for X-ray Flashes
The most intense X-ray emission in the Blackjack V plasmas came from center of
the spiral form.
This was evocative of the high-energy bursts from galactic centers that
cosmologists were trying to explain in terms of black holes and other exotic
concepts. Blackjack V didn't use black holes. But there was a way in which
sudden explosive releases of energy could come about from purely electrical
causes
the same that sometimes cause the plug of an appliance to spark when it's
pulled out of a wall socket.
An electric field that drives currents and accelerates particles in a
cyclotron, a neon light, or a TV
tube is produced by a changing magnetic field (in other words, not by a steady
one). A magnetic field accompanies an electric current. In the late fifties,
Alfvén had been called in by the Swedish power company ASEA to investigate a
problem they were having with explosions in mercury arc rectifiers used in the
transmission grid. The rectifiers used a low-pressure mercury vapor cell
containing a current-carrying plasma. It turned out that under certain
conditions the ions and electrons forming the plasma could separate in a
positive-feedback process that created a rapidly widening gap in the plasma,
interrupting the current. The fall in the magnetic field that the current had
been supporting generated an electric field that built up a high voltage,
accelerating the electrons to the point where the ensuing heat caused an
explosion.
Alfvén's work had shown that analogous effects involving suddenly collapsing
magnetic fields could also operate at larger scales to produce such results as
solar flares. The energy released in such an event is nonlocal in that it
derives not just from the conditions pertaining at the point where the current
break occurs, but from the magnetic field sustained around the entire circuit.
The energy stored in a galactic circuit thousands of light-years long and
carrying ten million trillions of amperes can be a staggering 10
57
ergs as much energy as a typical galaxy generates in 30 million years. The
electric fields produced by that kind of release could accelerate electrons to
enormous velocities, approaching that of light.
Accelerated charges radiate electromagnetic waves. Black-hole-density
concentrations of gravity are not necessary to generate jets of radio
brilliance that can be heard on the far side of the universe.
Eric Lerner and the Plasma Focus
Peratt published his findings in a small astronomy journal, Astrophysics and
Space Science, in
1983, and the following year in the more widely read amateur magazine
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Sky and Telescope
. Little
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reaction came from mainstream astrophysicists. Then, toward the end of 1984,
he was contacted by
Eric J. Lerner, a theoretician who had been pursuing a parallel line of
thought, though not within the recognized establishment. Lerner's interest in
the subject had been stimulated at an early age by an illustration in an
astronomy book of all the trains that would be needed to haul the billions of
tons of coal whose burning would equal the Sun's output in one second. He
studied physics at Columbia University and the University of Maryland, with an
emphasis on nuclear fusion, and in the mid seventies formed an association
with Winston Bostick, who was working on an approach to controlled fusion
known as the plasma focus. Invented independently in the sixties by a Soviet,
N. V. Filippov, and an American, Joseph Mather, the device first compresses
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electrical energy a millionfold into a sub-millimeter-size donut of
filamentary plasma called a plasmoid, and then collapses the associated
magnetic field to shoot out two intense, high-energy beams, each in the order
of a micron (one ten-thousandth of a centimeter)
wide electrons in one direction and ions in the other. In the course of this,
some of the confined ions are heated to sufficient temperatures to fuse.
Bostick too thought that filamentary processes might be involved in galaxy
formation, and this led
Lerner to wonder if something like the energy concentration mechanism of the
plasma focus might account for the distant, highly energetic, yet compact
quasars mentioned earlier. Since 1980, the new
Very Large Array (VLA) radio telescope, consisting of twenty-seven dish
antennas spread over miles of the New Mexico desert, had revealed enormously
energetic jets of energy emanating from quasars,
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