Machine that ate the world

SUBHEAD: As if there wasn't enough to worry about - LHC atom smasher exposes hole in Earth’s defenses against scientific experimentation.

By Kevin Hassett on 11 January 2010 in Bloomberg News - 
  (http://www.bloomberg.com/apps/news?pid=20601039&sid=acnHtIDcdERA

 
Image above: interior of underground 15 mile diameter LHC tunnel - the largest machine in the world. From http://lhc-machine-outreach.web.cern.ch/lhc-machine-outreach/lhc_in_pictures.htm 
 The largest machine in the history of the world has gradually begun to operate in a small town outside Geneva. The policy questions that the endeavor raises are bigger than the machine. The Large Hadron Collider (LHC) is the most ambitious physics experiment ever. Buried in deep underground tunnels and covering a loop of about 16.5 miles, it consumes about the same amount of energy as a large city. The LHC will explore the most important unresolved questions in physics. In particular, it could provide evidence of the existence of the Higgs boson, a hypothesized particle that has become known as the God particle. If it is found to exist, it could complete our understanding of the basic laws of the universe.

Accelerators such as the LHC work by bashing energetic beams of particles together, then studying the detritus. The high-energy LHC is like a telescope with an extra-powerful lens. It will allow scientists to see things they have never seen before, because its energy is about seven times greater than that of the most powerful accelerator to date. That high energy has caused significant controversy.

Some have warned that the collider’s energy could induce a catastrophic event. A brilliant review of the risks associated with the experiment by University of North Dakota law professor Eric Johnson has made me think twice about an experiment I have always favored. There are many things that theoretically could go terribly wrong, some of them quite exotic. The chief threat is that the LHC’s high-energy collisions might create a microscopic black hole that would, perhaps over a few years, swallow the Earth.  

Raised Before
As Johnson documents, the issue was raised in the late 1990s when some questioned whether a smaller experiment at the physics laboratory in Brookhaven, New York, might create a black hole -- an area of space with such a strong pull of gravity that not even light can escape. That experiment was allowed to proceed because a safety study concluded that the energy levels of the experiment were far too small to cause a hazard. Unfortunately, subsequent research by physicists at the University of California-Santa Barbara, Stanford University and Brown University showed that it was theoretically possible that much lower energy levels could create black holes.

One paper even suggested that something with the energy level of the LHC might generate one black hole per second. With its initial safety argument under assault, the physics community turned to an alternative. Even if a black hole were created, this new argument went, it would be tiny and would evaporate harmlessly. This was consistent with a theory of physicist Stephen Hawking. The evaporation argument was widely viewed as sound, and the LHC continued on track.  

Assurance Evaporates
But later, some top scholars began to publish papers questioning the evaporation hypothesis. The issue is far from decided. So the physics community retreated to what originally seemed like a terrific point: High-energy cosmic rays constantly bombard Earth and collide with particles in the atmosphere. If those collisions were going to create a black hole, then Earth would already be gone. It turns out that this argument, too, is a loser. When a cosmic ray rocketing toward Earth collides with a particle, the result of the collision would most likely be blasted into space.

That means a black hole created by such a collision might be well beyond our galaxy before it is large enough to harm anything. In the LHC, by contrast, the result of collisions between two particle beams might stay put and cause significant trouble. Thus, the safety arguments that have justified turning on the LHC are each a little less decisive than was originally believed. Oxford University’s Toby Ord, a philosopher by training, adds one last concern. It may be that the models that we use to make predictions about the possibility of catastrophe are themselves flawed.

 One in 1,000
Adjusting for this possibility, Ord estimates that the odds of the LHC producing a disaster are between one in 1,000 and one in 1 million. Whatever the likely benefits from this experiment, it is impossible that they would be significant enough to justify accepting a cost that includes a real risk of the Earth’s destruction. If Ord’s numbers are correct, and they may not be, then the LHC is the biggest policy error of all time.

As science progresses, the possibility climbs ever higher that the fondest dreams of scientists might entail risks of planetary destruction -- whether it’s the next physics experiment at even-higher energy or a genetic experiment that might unleash the perfect disease. The best science explores things far from our understanding. How can we know that things we do not understand will not kill us?  

Worldwide Void
Right now, the world’s governments have no mechanism to coordinate rational thinking about these risks. If the U.S. wanted to stop the LHC experiment, it would have no recourse short of military action. Early in his term, President George W. Bush appointed a bioethics panel to consider the weighty questions that scientific advances presented. A successor panel named by President Barack Obama has a lamentably narrow focus. It is urgent that a panel be assembled to explore policy in the presence of catastrophic scientific risks.

The alternative is to continue to bet the future of our planet on a process that keeps producing safety assurances that are subsequently refuted. (Kevin Hassett, director of economic-policy studies at the American Enterprise Institute, is a Bloomberg News columnist. He was an adviser to Republican Senator John McCain of Arizona in the 2008 presidential election.

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