Readers may recall back in 2002 there was an awful fuss kicked up when Rusi Taleyarkhan announced he had achieved one of science's holy grails: tabletop fusion. The claim was met with understandable scepticism, after all we'd been here before.
The promise of limitless, greenhouse gas-free, nuclear waste-free energy was too great to ignore however, and millions of tax dollars were sunk into trying to replicate the "star in a jar" experiments.
Today marks the fourth anniversary of the original announcement and four years in which nobody outside Taleyarkhan's research group has been able to reproduce the positive results.
Now, even Taleyarkhan's colleagues at his new home of Purdue University, West LaFayette, Indiana, are publicly doubting the work, Nature reports.
Purdue faculty members Lefteri Tsoukalas and Tatjana Jevremovic, along with others who wished to remain anonymous, said that since Taleyarkhan began working there he has removed the equipment they were using to try and replicate his work. Taleyarkhan has also not let anyone else see the raw data from the runs he claims produced neutrons, the scientists told Nature.
Taleyarkhan's big idea of sonoluminescent fusion involves firing soundwaves at a container of bubbling acetone "seeded" with a beam of neutrons. The theory goes that the tiny bubbles expand and then violently collapse, producing extreme temperatures as hot as the centre of the sun, thereby hot enough to fuse hydrogen nuclei provided in the mix by heavy water.
The Purdue researchers claim Taleyarkhan even tried to stop publication of their own, negative results.
Brian Naranjo at the University of California, Los Angeles, is set to add to his woes with an analysis of more recent data that suggests he didn't detect genuine fusion, but a background lab source of neutrons.
Taleyarkhan defended his findings in a 2005 episode of the BBC's Horizon strand, protesting: "My lab has been audited, my instruments have been audited, my books have been audited, the data speaks for itself."
Though the consensus is that bubble fusion is theoretically possible, without a lusty rebuttal these latest blows could sound the death knell. ®