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Black holes are theorized to be regions in space where the gravitational
field is so strong that nothing can escape its pull after crossing what is
called the event horizon. BlackMax simulates these regions.
Approximately two years in the making, the computer program enables
physicists to test theories about the production and decay of black holes and
takes into account new types of effects on both the creation and evaporation of
black holes at the new Large Hadron Collider (LHC) currently being commissioned
at the European Center for Nuclear Research (CERN) in Geneva, Switzerland.
For example, black holes created at the LHC would be expected to start off
spinning.
The spinning of the black hole increases the fraction of the black hole's
mass that is dissipated as gravitons–elementary quanta of gravity, which could
be used to provide a clue to the existence and structure of extra dimensions.
Black holes are being studied with BlackMax by members of the ATLAS Experiment
at LHC, one of the two principal large particle detectors at the new collider.
Case Western Reserve physicists working with Glenn Starkman on the project are
his former doctoral student Dejan Stojkovic, now a visiting professor on the
faculty of the State University of New York (SUNY) at Buffalo, and De-Chang Dai,
who recently graduated with his doctoral degree in physics, and is now a
postdoctoral fellow working with Stojkovic. Other collaborators are experimental
physicists Cigdem Issever and Jeff Tseng of Oxford University and Eram Rizvi
from Queen Mary College at the University of London.
ATLAS works much like investigators who search the site of plane crash, and
then piece together the debris to find the cause of the plane's
disintegration.
BlackMax, by predicting how those pieces will fall, should allow physicists
looking at data from the ATLAS experiment to see whether the pattern of
particles released into the detector matches what one would expect when a black
hole is produced and then falls apart.
The ordinary non-gravitational collisions predicted by the Standard Model of
particle physics tend to produce fragments of the proton clumped into a small
number of jets.
Decays of black holes should produce more particles than usual. These
particles should also come out unusually isotropically—in every direction—and
the mix of particles should be more democratic - including for example electrons
and similar particles that are not found within the proton.
Under certain circumstances, black hole decay should also produce many
gravitons that would themselves pass unnoticed out of the ATLAS, but which would
make the remaining emitted particles looking asymmetric and carrying less than
the full event energy.
Starkman said that if black holes are found at the LHC it will enable
scientists to understand the connection between gravity and quantum mechanics,
resolving the inconsistency between two of the great intellectual triumphs of
the 20th century - quantum mechanics and Einstein's General Theory of
Relativity.
It would also mean the existence of other dimensions to space, and explain
why gravity is such a weak force compared to the other three fundamental forces
of nature–electromagnetism and the strong and weak nuclear forces.
According to Starkman, the black holes under study at LHC will be very small,
extremely hot at more than billion times the temperature of the sun, and their
lifespan will consequently be so short that they will decay within tiny
fractions of a second of their creation.
He added that there is not enough time for the black hole to cross a human
hair, "never mind leaving the detector," he said.
"What's more important is that the universe has been doing this experiment
for billions of years by bombarding the earth's atmosphere (not to mention all
the myriad stars) with cosmic rays. So we know if black holes are made at the
LHC, they are entirely safe," said Starkman. //11.11.08
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