Bubble Fusion Burst

A Purdue University nuclear engineering professor, Rusi P. Taleyarkhan, who reported having achieved "tabletop" nuclear fusion by sonoluminescence, later falsely published claims that the study had been independently replicated, according to an academic committee investigating his research.

The committee stressed that its investigation did not address whether Taleyarkhan doctored his original data. Whether or not this is the case is "the truly important question that remains unanswered," says University of Illinois, Urbana-Champaign, chemistry professor Kenneth S. Suslick, a vocal critic of Taleyarkhan's work and whose lab has attempted to replicate it without success.

Taleyarkhan first stirred up controversy in 2002 when he was a scientist at Oak Ridge National Laboratory. He reported bombarding deuterated acetone with high-energy sound waves, causing bubbles to form, expand, and implode with great energy (Science 2002, 295, 1868). Taleyarkhan claimed he had observed characteristic radioactive particles that suggested deuterons had fused in the implosion. The possibility of a cheap, plentiful energy source captured worldwide attention and also generated skepticism.

After several labs failed to replicate Taleyarkhan's difficult experiments, criticism of his work grew more vocal. Then, in 2005, Purdue postdoctoral researcher Yiban Xu and graduate student Adam Butt reported that they'd succeeded in reproducing the findings (Nucl. Eng. Des. 2005, 235, 1317). Taleyarkhan then published a paper saying his results had been "independently confirmed" (Phys. Rev. Lett. 2006, 96, 034301).

The committee investigating Taleyarkhan's claims—made up of seven independent faculty and researchers from different institutions—has now determined that he was heavily involved in Xu's project and that Taleyarkhan added Butt's name to the paper despite the student's small contribution.

Taleyarkhan could not be reached for comment, but according to a Purdue University statement, he has 30 days to respond to the committee's findings.

Lawrence A. Crum, an engineering professor at the University of Washington and whose lab has also been unable to replicate Taleyarkhan's work, says he believes Taleyarkhan got caught up in defending his results and lost his objectivity.

Taleyarkhan's results "would have been a wonderful scientific discovery," Crum tells C&EN. "This is more a case of the psychological stresses of scientific research than it is of fraud and misconduct."