Physicists create BlackMax to search for dimensions in space at the Large Hadron Collider
November 7th, 2008A team of theoretical and experimental physicists, with participants from Case Western Reserve University, have designed a new black hole simulator called BlackMax to search for evidence that extra dimensions might exist in the universe.
Information about BlackMax's creation has been published in Physical Review Letters in the article, "BlackMax: A Black-Hole Event Generator with Rotation, Recoil, Split Branes and Brane Tension."
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.
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.
Source: Case Western Reserve University
May 18, 2009 |
not rated yet |
0
A computer simulation only knows what you program it with. Thus if the theory was wrong to begin with, or the programming logic flawed, then the test results will be wrong, and so will the scientists conclusions.
Simulations, like any properly used tool, serve a purpose.
If the simulation is incorrect it is useless or worse, misleading.
The head-to-head collisions of high proton density flux bellow Earth surface cannot be compared in safety with rare collisions of individual protons in high altitudes.
Simulations usually (if they're done well) produce testable results -- for instance, they may predict several things, some of which we can compare against reality. If the simulation predicts that Newton should float up to hit the apple, for instance, we probably have to rework it. If the simulation correctly predicts several things that are actually observed (or can be calculated based on known physical behaviours), then the "novel" behaviour that the simulation is actually testing for has a good chance of being correct, or at least close.
yes, true, which can be useful if
one maintains awareness that the
results are ONLY valid within the
simulation! and thaT is the extent
of what a sim can prove! So often
we read of this or that being
"proved" by a computer sim ..
Such conclusions are inappropriate.
And you need to remember that most of the time you are reading a pop article based on a summary based on a capsule interpretation based on maybe a couple more layers before you get to what the actual scientists actually said. Each step simplifies things even if it doesn't distort.
Posted by Alexa 3 hours ago
Rank: 1.5/5 after 2 votes
universe has been doing this experiment for billions of years by bombarding the earth's atmosphere .. with cosmic rays
If so, why the black holes aren't produced by the same way in LHC? Such arguments are incredibly demagogical or silly, presumably the both.
The head-to-head collisions of high proton density flux bellow Earth surface cannot be compared in safety with rare collisions of individual protons in high altitudes.
Alexa - the energy density is routinely exceeded, some cosmic rays are up to 2 joules per particle (10^19 eV, compared to 10^12 eV at CERN)
And of course, the moon, for instance, has no upper atmosphere - the natural collisions occur in dense material.
Check it's still up there for me, would you??
only kidding, your concerns are fair, a consequence (of earth wipeout) needs some pretty strong risk analysis, but i'm happy that the integrated exposure of billions of years and the 10^7 multiplier on energy make it safe.
One might compare it to the risks to the whole food chain (another wipeout scenario) posed by "terminator" genes and "Bt" (i.e. botulism toxin) genes that are being introduced into farming... but hey, life's been on this planet for ages and genes have never migrated from one species to another...
However genes do move from species to species all the time! Some move in from bacterial infections (Google "Wolbachia bacterium genome"), but many are picked up by viruses and moved to totally different species, and even different kingdoms.
For example, the gene for Taxol apparently migrated from the bark of the pacific yew to a fungus! (Google "taxol yew fungus gene transfer").
The math used in the simulations is worked to its conclusion. Nothing more....
The problem with simulation is that you can use non-real parameters and never know it, well maybe you do but it works and you dont care.....GIGO.
Thanks for that RealScience. Wikipedia has a really interesting article under "Horizontal gene transfer". Some biologists would like to see the 'tree of life' metaphor replaced by a 'net' analogy - at least for microbes.
This is not true.
Very nice thinking.
No doubt about that: In the 19th century scientists were not fighting for funds. Most of them were well-off gentlemen who had their own labs. Since the 1930's many things have changed. Delusions have become entrenched as scientific fact; and beware the scientist who questions these delusions. He/she is excommunicated and "shunned". Richard Dawkins' "The God Delusion" is nothing compared to "The Physics Delusion". Believers in God are more honest than physicists because they do not claim dishonestly that they have open minds while being THE REAL bigots in the world. Organised religion can nowadays learn from our scientific societies like the AAAS and the publishing houses like NATURE how to censor new ideas which contradict the dogma of the "holy physicist-saints".
Very nice. Thank you.
Cause if thats true scientists there is no way you can develope an universal black hole theory. And this is what you will not understand for next 500 years.