Sonofusion

Tiny bubbles imploded by sound waves can make hydrogen nuclei fuse—and may one day become a revolutionary new energy source. Imagine sound waves producing in bubbles, even briefly, the extreme temperatures and pressures created by the lasers or magnetic fields, which themselves replicate the interior conditions of stars like our sun, where fusion occurs steadily. Nevertheless, three years ago, Purdue University in West Lafayette, Ind.; Rensselaer Polytechnic Institute in Troy, N.Y.; and the Russian Academy of Sciences branch in Ufa obtained strong evidence that such a process—now known as sonofusion is indeed possible.

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