| The
ultimate destiny of our expanding universe depends on how much matter it contains and
whether that will be enough to one day stop the expansion. When astronomers count up all
the visible matter—the stuff that gives off light—the answer is clearly no. But
they have learned over the past several decades that the answer isn’t so
cut-and-dried. Observations reveal that vast halos of invisible matter surround galaxies
and galaxy clusters. This dark matter adds up to about ten times more mass than the
visible stars, gas, and dust seen in galaxies. And there may be more. The inflationary
theory, if true, demands that this dark stuff makes up between 90 and 99 percent of the
universe. Astronomers have yet to determine what constitutes this dark matter, although
some leading candidates go by the names MACHOs, WIMPs, and neutrinos. MACHOs
Short for MAssive Compact Halo Objects,
MACHOs could exist in huge numbers in vast halos surrounding galaxies. In the past few
years, astronomers have detected several examples of MACHO-like objects in our galaxy,
though not yet enough to account for all the dark matter known to reside there. Brown
dwarfs, with a size between normal stars and planets, could be one type of MACHO. These
objects form like stars but don't have enough mass to begin the nuclear fusion reactions
that cause stars to shine brightly. Other candidate MACHOs include planets, about a dozen
of which have been discovered outside our own solar system in the past couple of years,
and the halo objects that have recently been detected as they magnify and distort the
light from stars in nearby galaxies.
WIMPs
Short for Weakly Interacting
Massive Particles, the ghostly WIMPs are predicted by theory but have so far eluded
detection. With odd names like photino and masses of perhaps 10 to 100 times that of the
proton, WIMPs could account for lots of dark matter if, as some theories predict, they are
common in the universe. Cosmologists like cold-dark-matter WIMPs because they would be
relatively heavy and thus move much slower than the speed of light. If so, they could have
been the gravitational “seeds” around which regular matter congregated to form
galaxies yet, because they don't interact with radiation, not affect the observed
smoothness of the cosmic background radiation.
HOT AND COLD DARK MATTER
The
temperature of dark matter is a measure of how fast the particles making it up move, with
hot referring to particles moving near the speed of light (neutrinos, for instance) and
cold to particles moving much slower than that. The fate of our universe depends on how
much dark matter exists—more dark matter means the universe will eventually collapse
while less means an ever-expanding universe—and not whether it is hot or cold. But
hot and cold dark matter play a crucial role in understanding how galaxies formed. If all
dark matter in the early universe were cold, galaxies would form first and later
congregate into clusters. However, the huge voids and long structures observed by
astronomers would not develop. If all the dark matter were hot, large-scale structure
would come first with individual galaxies forming later. But in this scenario, galaxies
would have formed too late to account for observations of objects such as quasars. The
most recent observations and computer simulations seem to point toward a universe with a
mixture of both hot and cold dark matter.
HOW TO USE DARK MATTER
Dark Matter has also been overrated. As said above, the prime
elements that make up Dark Matter is still unkown leaving a gap of possible
interpretations, that can both be reasonable, and compeletly absurd. Dark Matter has been
detected only by the means of gravitational force throughout the Universe. Many suspect
the Dark Matter is linked to another possible dimension. It is clear that Dark Matter does
have potential energy storage, that would be practically interminable. Gaining access to
such matter would really depend on the character's prime abilities. Psionics for example
would be exceptional, but the character must have a strong sensitivity to be to detect the
Dark Matter. Dark Matter may also have time variations. As of now, DM is left open for
reasonable interpretations. What is really going to be the hard part if finding any
benefits to using Dark Matter. |
