Scientists: Nothing to fear from atom-smasher

[Every Breaking Wave]

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The most powerful atom-smasher ever built could make some bizarre discoveries, such as invisible matter or extra dimensions in space, after it is switched on in August.

But some critics fear the Large Hadron Collider could exceed physicists' wildest conjectures: Will it spawn a black hole that could swallow Earth? Or spit out particles that could turn the planet into a hot dead clump?

Ridiculous, say scientists at the European Organization for Nuclear Research, known by its French initials CERN — some of whom have been working for a generation on the $5.8 billion collider, or LHC.

"Obviously, the world will not end when the LHC switches on," said project leader Lyn Evans.

David Francis, a physicist on the collider's huge ATLAS particle detector, smiled when asked whether he worried about black holes and hypothetical killer particles known as strangelets.

"If I thought that this was going to happen, I would be well away from here," he said.

The collider basically consists of a ring of supercooled magnets 17 miles in circumference attached to huge barrel-shaped detectors. The ring, which straddles the French and Swiss border, is buried 330 feet underground.

The machine, which has been called the largest scientific experiment in history, isn't expected to begin test runs until August, and ramping up to full power could take months. But once it is working, it is expected to produce some startling findings.

Scientists plan to hunt for signs of the invisible "dark matter" and "dark energy" that make up more than 96 percent of the universe, and hope to glimpse the elusive Higgs boson, a so-far undiscovered particle thought to give matter its mass.

The collider could find evidence of extra dimensions, a boon for superstring theory, which holds that quarks, the particles that make up atoms, are infinitesimal vibrating strings.

The theory could resolve many of physics' unanswered questions, but requires about 10 dimensions — far more than the three spatial dimensions our senses experience.

The safety of the collider, which will generate energies seven times higher than its most powerful rival, at Fermilab near Chicago, has been debated for years. The physicist Martin Rees has estimated the chance of an accelerator producing a global catastrophe at one in 50 million — long odds, to be sure, but about the same as winning some lotteries.

By contrast, a CERN team this month issued a report concluding that there is "no conceivable danger" of a cataclysmic event. The report essentially confirmed the findings of a 2003 CERN safety report, and a panel of five prominent scientists not affiliated with CERN, including one Nobel laureate, endorsed its conclusions.

Critics of the LHC filed a lawsuit in a Hawaiian court in March seeking to block its startup, alleging that there was "a significant risk that ... operation of the Collider may have unintended consequences which could ultimately result in the destruction of our planet."

One of the plaintiffs, Walter L. Wagner, a physicist and lawyer, said Wednesday CERN's safety report, released June 20, "has several major flaws," and his views on the risks of using the particle accelerator had not changed.

On Tuesday, U.S. Justice Department lawyers representing the Department of Energy and the National Science Foundation filed a motion to dismiss the case.

The two agencies have contributed $531 million to building the collider, and the NSF has agreed to pay $87 million of its annual operating costs. Hundreds of American scientists will participate in the research.

The lawyers called the plaintiffs' allegations "extraordinarily speculative," and said "there is no basis for any conceivable threat" from black holes or other objects the LHC might produce. A hearing on the motion is expected in late July or August.

In rebutting doomsday scenarios, CERN scientists point out that cosmic rays have been bombarding the earth, and triggering collisions similar to those planned for the collider, since the solar system formed 4.5 billion years ago.

And so far, Earth has survived.

"The LHC is only going to reproduce what nature does every second, what it has been doing for billions of years," said John Ellis, a British theoretical physicist at CERN.

Critics like Wagner have said the collisions caused by accelerators could be more hazardous than those of cosmic rays.

Both may produce micro black holes, subatomic versions of cosmic black holes — collapsed stars whose gravity fields are so powerful that they can suck in planets and other stars.

But micro black holes produced by cosmic ray collisions would likely be traveling so fast they would pass harmlessly through the earth.

Micro black holes produced by a collider, the skeptics theorize, would move more slowly and might be trapped inside the earth's gravitational field — and eventually threaten the planet.

Ellis said doomsayers assume that the collider will create micro black holes in the first place, which he called unlikely. And even if they appeared, he said, they would instantly evaporate, as predicted by the British physicist Stephen Hawking.

As for strangelets, CERN scientists point out that they have never been proven to exist. They said that even if these particles formed inside the Collider they would quickly break down.

When the LHC is finally at full power, two beams of protons will race around the huge ring 11,000 times a second in opposite directions. They will travel in two tubes about the width of fire hoses, speeding through a vacuum that is colder and emptier than outer space.

Their trajectory will be curved by supercooled magnets — to guide the beams around the rings and prevent the packets of protons from cutting through the surrounding magnets like a blowtorch.

The paths of these beams will cross, and a few of the protons in them will collide, at a series of cylindrical detectors along the ring. The two largest detectors are essentially huge digital cameras, each weighing thousands of tons, capable of taking millions of snapshots a second.

Each year the detectors will generate 15 petabytes of data, the equivalent of a stack of CDs 12 miles tall. The data will require a high speed global network of computers for analysis.

Wagner and others filed a lawsuit to halt operation of the Relativistic Heavy Ion Collider, or RHIC, at the Brookhaven National Laboratory in New York state in 1999. The courts dismissed the suit.

The leafy campus of CERN, a short drive from the shores of Lake Geneva, hardly seems like ground zero for doomsday. And locals don't seem overly concerned. Thousands attended an open house here this spring.

"There is a huge army of scientists who know what they are talking about and are sleeping quite soundly as far as concerns the LHC," said project leader Evans.

 

[GrnMarvl14]

Isn't "nothing to fear" what every scientist in every B-grade horror movie says before they're killed by whatever it is we shouldn't "fear"?

One in 50 million chance of this causing a global catastrophe. I'm not against this being used...I just don't like people tempting whatever fates may exist by saying we have nothing to fear. It's when you taking something lightly that said thing mauls you and rips out your throat.

 

[Æsahættr]

If it did go wrong, and we all perished, we would have the best bragging rights over everyone else in whatever afterlife there may be.

See? look on the bright side.

 

[Luphinid Silnaek]

I feel that certain deaths are worth dying, however one might love life. This is one of them.

This is also precisely why it cannot happen. [DISCLAIMER: THIS IS NOT SCIENTIFIC ARGUMENT AGAINST ITS POSSIBILITY]

 

[evkl]

Black holes only have noticeable gravity effects close to their swarzchild radius. If the sun was replaced by a black hole of equal mass, minus the whole no-light issue, Earth would just keep on spinning around that same central point.

 

[GrnMarvl14]

But the issue here is that one might be created ON Earth itself. Which, you have to admit, is a tad more frightening. Though it would be interesting to see what's beyond the event horizon.

 

[Transfinite]

If a microscopic black hole was created, it would dissipate from Hawking radiation so quickly that it wouldn't cause any problems.

...and in answer to evkl's point, if the sun were replaced by a black hole of equal mass, there might not be any weird effects to the gravity, but we would die of cold pretty quickly.

 

[GrnMarvl14]

If a microscopic black hole was created, it would dissipate from Hawking radiation so quickly that it wouldn't cause any problems.

Hence why it's likely to not be a problem. I'm just struck by the sci-fi irony of "there's nothing to fear from the machine that might create a black hole."

Likely nothing WILL happen, but if movies have taught me anything, it's that what what's least likely to happen, WILL happen. Which is why I fear ice spiders.

 

[Barb]

This reminds me; I need to re-read Douglas Preston's "Blasphemy".

 

[evkl]

Even if Hawking radiation doesn't exist (and there's debate on this point), let's say you have a black hole with the mass of the earth--I believe that yields a radius of roughly a centimeter or two. If you were even a meter away, I doubt you would know the black hole existed. Minus the little black vortex slowly consuming your world.

But seriously, we aren't even going to create a point-mass a centimeter in radius. If it's one-millionth that size, it'd be simply insignificant.

 

[Amewsment]

Hawkings has it all figured out!

Hawkings is being pretty clever! If things actually do go to hell and it turns out that there is no radiation that cancels it out, noone will be able to tell him he was wrong afterwards.

 

[The Big Al]

Any black holes created by smashing protons would be so small they could pass between the proton and electron of a hydrogen atom without effecting it. And because the accelerator will be kept in a better vacuum than that space, there wouldn't be much more matter to consume.

Though, being able to create black holes could pose issues in the future. I know black hole generators have been a favorite weapon of science fiction writers for decades. We might accidentally fall into that technology with miniaturization being the only hurtle.