NEW YORK, March 5 (UPI) -- News about bubble fusion -- a method to mimic the energy process that powers the sun with a relatively simple table-top apparatus -- has drawn super-heated fire of a different kind as scientists around the world Tuesday quarreled over the results.
Fusion -- when atoms fuse together -- releases enormous energy and is a potential source of cheap, clean, non-radioactive power. Fusion is a natural process at the core of the sun, but artificial fusion has required extremely high pressures and temperatures created by powerful magnetic fields or high-energy lasers. A simple method of fusion potentially could solve the world's energy problems.
The researchers claim the sudden implosion of tiny bubbles -- each inflated by sound waves from billionths of a meter wide to thousands of times that in size -- may generate the necessary conditions for table-top fusion.
Rusi Taleyarkhan and colleagues at Oak Ridge National Laboratory in Oak Ridge, Tenn., claimed in a report released Monday to have generated evidence of fusion by firing high-pressure sound waves at tiny bubbles dissolved in chilled, neutron-loaded acetone. The container they used is only about as high as a stack of three coffee mugs.
At best, scientists met these new findings with caution.
"Extraordinary claims require unambiguous evidence, and in my opinion they have not provided the evidence -- but that doesn't mean fusion isn't there," said physicist William Moss of Lawrence Livermore National Laboratory in Livermore, Calif.
The controversy turned particularly messy, as lead researcher Rusi Taleyarkhan's own lab colleagues publicly argued with him over the findings.
In some respects, this is exactly the type of fervor scientists love.
"We're looking forward to the next step -- to help scientists attempt the same results anywhere they are in the world," Taleyarkhan told United Press International from home.
Though the researchers insist this is not cold fusion, saying they've reached heat levels of 10 million degrees Celsius -- as hot as the core of the sun -- many researchers remember with rancor the hope, hoopla and ultimate disappointment generated by the cold fusion claims of 1989.
"Science is tough stuff and it's easy to be fooled by Mother Nature," said physicist Bob Park of the American Physical Society. "It turned out in the cold fusion fiasco, (the researchers) were simply inexperienced at neutron spectroscopy, and so are the people that published this paper. And this paper is being published with a great deal of fanfare -- they're planning on making it the cover of Science magazine this week. That sets off a few alarm bells too."
Moss, who first proposed the idea of tabletop fusion years ago, remains unconvinced by the data. Two of Taleyarkhan's fellow physicists at Oak Ridge -- Dan Shapira and Michael Saltmarsh -- said they repeated the experiment only to find no signs of fusion whatsoever.
"In science, you're guilty until proven innocent -- the burden of proof is on the scientists. Otherwise there'd be chaos. And the evidence isn't there," Moss said. "There's no free lunch."
Taleyarkhan and his colleagues, upon reviewing Shapira and Saltmarsh's data, countered that the two physicists did in fact detect neutron emissions -- a telltale sign of fusion -- but that they had improperly calibrated their detector and thus misinterpreted their findings.
"Contrary to their conclusions, a statistically significant increase of nuclear emissions was actually detected by them," Taleyarkhan and his team said. The researchers earlier found the bubbling process generates roughly seven tritium atoms -- hydrogen atoms loaded with two neutrons each -- per minute over a seven-hour period as well as about 1 million neutrons per second, which they say is strong evidence of fusion.
Moss said that even if bubble fusion can exist, fantasies of clean, cheap power might remain only that.
"If you were to tile the world with these devices and let them run for an hour, there'd be enough thermonuclear energy to heat a cup of coffee 1 degree," Moss told UPI. "The likelihood that you could produce energy you could use is very, very slim -- but I'm not saying zero."
Physicist Fred Becchetti of the University of Michigan in Ann Arbor said there are dozens of labs around the world that can try out the experiment within weeks. Moss expects people to do so.
"The allure is that it might be able to be done easily, to try and make nature do something it really doesn't want to," Moss said. "Is it a dead end? I don't think there's necessarily any avenue in science that's a dead end. Is it research I'm going to pursue? No."
