FROM a distance, the plastic wafer Frank Gordon is proudly displaying looks like an ordinary microscope slide. Yet to Gordon it is hugely more significant than that. If he is to be believed, the pattern of pits embedded in this unassuming sliver of polymer provides confirmation for the idea that nuclear fusion reactions can be made to happen at room temperature, using simple lab equipment. It's a dramatic claim, because nuclear fusion promises virtually limitless energy.

Gordon's plastic wafer is the product of the latest in a long line of "cold fusion" experiments conducted at the US navy's Space and Naval Warfare Systems Center in San Diego, California. What makes this one stand out is that it has been published in the respected peer-reviewed journal Naturwissenschaften, which counts Albert Einstein, Werner Heisenberg and Konrad Lorenz among its eminent past authors (DOI: 10.1007/s00114-007-0221-7). Could it really be true that nuclear fusion ...