One
of the most fascinating discoveries of our new century may be imminent
if the Large Hadron Collider outside Geneva produces nano-blackholes. According to the best current physics, such
nano blackholes could not be produced with the energy levels
the LHC can generate, but coud only come into being if a parallel
universe were providing extra gravitational input. Versions of
multiverse theory suggest that there is at least one other universe
very close to our own, perhaps only a millimeter away. This makes it
possible that some of the effects, especially gravity, “leak through,”
which could be responsible for the production of dark energy and dark
matter that make up 96% of the universe.
At a recent CalTech roundtable conference on the possible impact of the LHC on physics, Neal Weiner of
New York University, who is a proponent of the existence of forces as well
as particles on the dark side, said that until recently our theories about
dark matter were driven by ideas about particle theory rather than
data. "Ultimately we learn that perhaps it has very little to do with
us at all," Dr. Weiner said. "Who knows what we will find in the dark
sector?"
A huge volume of space that includes the Milky Way and
super-clusters of galaxies is flowing towards a mysterious, gigantic unseen mass named mass astronomers have dubbed “The Great
Attractor,” some 250 million light years from our Solar System.
The Milky Way and Andromeda galaxies are the dominant structures in
a galaxy cluster called the Local Group which is, in turn, an outlying
member of the Virgo supercluster. Andromeda–about 2.2 million
light-years from the Milky Way–is speeding toward our galaxy at
200,000 miles per hour.
This motion can only be accounted for by
gravitational attraction, even though the mass that we can observe is
not nearly great enough to exert that kind of pull. The only thing that
could explain the movement of Andromeda is the gravitational pull of a
lot of unseen mass–perhaps the equivalent of 10 Milky Way-size
galaxies–lying between the two galaxies.
Meanwhile,
our entire Local Group is hurtling toward the center of the Virgo
Cluster (image above) at one million miles per hour.
The Milky Way and its neighboring Andromeda galaxy, along with some
30 smaller ones, form what is known as the Local Group, which lies on
the outskirts of a "super cluster"—a grouping
of thousands of galaxies—known as Virgo, which is also pulled toward
the Great Attractor. Based on the velocities at these scales, the
unseen mass inhabiting the voids between the galaxies and clusters of
galaxies amounts to perhaps 10 times more than the visible matter.
Even
so, adding this invisible material to luminous matter brings the
average mass density of the universe still to within only 10-30 percent
of the critical density needed to “close” the universe. This phenomena
suggests that the universe be “open.” Cosmologists continue to debate
this question, just as they are also trying to figure out the nature of
the missing mass, or “dark matter.”
It is believed that this dark matter dictates the structure of the
Universe on the grandest of scales. Dark matter gravitationally
attracts normal matter, and it is this normal matter that astronomers
see forming long thin walls of super-galactic clusters.
Recent measurements with telescopes and space probes of the
distribution of mass in M31 -the largest galaxy in the neighborhood of
the Milky Way- and other galaxies led to the recognition that galaxies
are filled with dark matter and have shown that a mysterious force—a
dark energy—fills the vacuum of empty space, accelerating the
universe’s expansion.
Astronomers now recognize that the
eventual fate of the universe is inextricably tied to the presence of
dark energy and dark matter.The current standard model for cosmology
describes a universe that is 70 percent dark energy, 25 percent dark
matter, and only 5 percent normal matter.
We don’t know what
dark energy is, or why it exists, or if it even does exist. On the other hand, particle theory
tells us that, at the microscopic level, even a perfect vacuum bubbles
with quantum particles that are a natural source of dark energy. But a
naïve calculation of the dark energy generated from the vacuum yields a
value 10120 times larger than the amount we observe. Some unknown
physical process is required to eliminate most, but not all, of the
vacuum energy, leaving enough left to drive the accelerating expansion
of the universe.
A new theory of particle physics is required to explain this physical process.
The
universe as we see it contains only the stable relics and leftovers of
the big bang: unstable particles have decayed away with time, and the
perfect symmetries have been broken as the universe has cooled, but the
structure of space remembers all the particles and forces we can no
longer see around us.
Discovering what it is that makes up the heart of the Great Attractor –
will surely rank as one of the greatest discoveries in the history of
science.
Last month, CERN's Large Hadron Collider, the most powerful particle accelerator
ever built, has begun colliding protons and generating sparks of
primordial fire in an effort to recreate conditions that ruled the
universe in the first trillionth of a second of time after the Big Bang. Physicists have been speculating for 30 years what they will see.
A major hope is an explanation for why gravity is so weak compared with the other forces of nature. How is it that a refrigerator magnet can hold itself up against the pull of the entire Earth? Perhaps they will discover what physicists call the "wimp miracle," previously undiscovered particles — known collectively as wimps, for weakly interacting massive particles, that supersymmetry predicts could explain the mysterious dark matter that astronomers believe makes up 25 percent of the universe.
Casey Kazan
Source
http://www.nytimes.com/2010/01/26/science/26essay.html
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