The Shadow Universe
December 17, 1985
A review of "The Shadow Universe" by Dennis Overbye.
Copyright © 1997 Property of Deborah K. Fletcher. All rights reserved.
This article was published in the May, 1985 issue of Discover. This
volume, as per usual, is a part of my personal library.
"Dark matter, mysterious and invisible, may make up 99 per cent of the cosmos
and provide the key to the origin of the galaxies and the fate of the universe."
Dark matter is among the newest phenomena which the world's astrophysicists are
using in their attempt to reconstruct the creationary forces of the universe. In 1980, neutrinos
were considered to be the basic substance of the universe.
Neutrinos are "massless, invisible particles that could race through millions of
miles of lead at the speed of light, and are so insubstantial that cubic light-years of them wouldn't
weigh a flea's breath." These particles, once considered the dominant mass of the cosmos, are
now becoming publicly inconsequential once again. The reason? Dark matter.
"The shadow universe may be ordinary matter that failed to achieve the grace of
light, exotic particles that have yet to be created in earthly accelerators, relic energy fields from
the Big Bang, or even forms of matter and energy for which science has no theory."
fritz Lwicky, an astronomer at Caltech, discovered in 1933 that the orbital velocity
of galaxies exceeded that which should have thrown them on tangent trajectories. This
discovery was based on mass. The fact that the galaxies maintained basically static orbits
indicated that they must be approximately ten times as massive as they seemed.
Vera Rubin, astronomer from the carnegie Institution, W. Kent Ford, Norbert
Thonnard, and David Burstein made a study of rotation curves for the Andromeda Galaxy.
Rotation curves should reveal the distribution of mass in a galaxy. At the outer edge of a galaxy,
the rotation curve should drop off. In the case of Andromeda, the rotation curve continued
beyond the galaxy. Not realizing what they had found, the scientists repeated their studies on
other galaxies. The rotation curves continued to register flat. Proof was forming for the theory,
presented by Jeremiah Ostriker and P.J.E. Peebles, both Princeton astronomers, that spiral
galaxies might be embedded in halos of material which prevented disc warping.
"... If there's enough of it, dark matter could some day cause the universe to
collapse in fiery and terminal splendor."
Aleksandr Friedmann, a russian mathematician, determined that the course of cosmic history is
determined by the rate of expansion of the universe - the Hubble constant - and omega. Omega
is the ratio of the density of the universe to roughly three hydrogen atoms per cubic yard. If
omega is greater than one, the combined gavities of cosmic matter will overcome universal
expansion and the cosmos will retract into a "Big Crunch." This is a closed universe.
If omega is less than one, the universe is open, infinite, eternal. This type of
universe is typified by eternal expansion, with matter being reduced to ash.
If omega is equal to one, the universe is flat, stable, and correct in respect to
Euclidian geometry.
According to Jim Gunn, astronomer at Caltech, at the beginning of the universe,
"dark and light matter were intermixed, but as the universe expanded, the dark stuff formed
clumps, pulling light stuff with it. The ordinary matter within these clumps cooled, like hot coffee
radiating away its heat, and sank to the centers. There is the seven per cent froth that you and I
are made of."
The dark matter, not being electromagnetic, couldn't radiate, and couldn't get rid of
energy acquired from falling together. The dark particles reacted with stellar-like gravity and
formed pressure-supported clouds around the light matter.
The subject of dark matter is still largely theory, but its implications have had
similar effects on the scientific world as those cause by facts - such as galaxies and rotation
curves. But are they facts? The answers may lie in the darkness before us.
The subject of dark matter intrigues me because a favorite passtime of mine is
discussing astro- and meta-physical creation of the universe with my colleagues.
I have learned from this article that the phrase "all is not as it seems" has scientific
bearing.
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