Surely you have heard of the supposed "cold fusion," first reported in 1989 at a press conference (super sketch!) by Drs. Stanley Pons and Martin Fleischmann at the University of Utah. But did you ever wonder what it was? Or whether it actually works?
Nuclear fusion refers to the process by which multiple nuclei of similarly charged atoms unite to form a heavier atom and typically A LOT OF ENERGY--with the exception of atoms heavier than iron, which actually absorb energy on fusion. Due to the typically high energy output, nuclear fusion could potentially provide a useful source of energy for our growing--and increasingly demanding--global population. One significant problem is that the process typically occurs only at ridiculously high temperatures, such as those found in the Sun or in a hydrogen bomb. Not surprisingly, scientists have long been interested in designing cheap, safe and effective methods for controlled fusion to produce usable energy.
Nuclear fusion refers to the process by which multiple nuclei of similarly charged atoms unite to form a heavier atom and typically A LOT OF ENERGY--with the exception of atoms heavier than iron, which actually absorb energy on fusion. Due to the typically high energy output, nuclear fusion could potentially provide a useful source of energy for our growing--and increasingly demanding--global population. One significant problem is that the process typically occurs only at ridiculously high temperatures, such as those found in the Sun or in a hydrogen bomb. Not surprisingly, scientists have long been interested in designing cheap, safe and effective methods for controlled fusion to produce usable energy.
Pons and Fleischman described a system containing deuterated water (D2O), two palladium electrodes, and a current running through the electrodes. They claimed that the current caused the palladium electrodes to absorb deuterium atoms, which were then forced so closely together that they underwent nuclear fusion to produce neutrons and energy in the form of heat: "...fusion occurs, out of that comes one or two new elements of less mass, and the difference is the energy that comes out. And that then would boil water, essentially. And when you boil water, you can make steam. And when you make steam, you can drive a turbine. And if you can drive a turbine, you can create electricity..." (watch the press conference).
The two scientists concluded that cold fusion had occurred based on the results of a calorimetric experiment that showed a 4:1 ratio of heat put into the experiment versus heat released. They also analyzed the gas released by the reaction by mass spectrometry and observed the presence of tritium. Finally, they claimed to have captured the ejected neutrons from the reaction vessel with water, and the water was found to emit gamma rays of a characteristic wavelength.
Skeptical scientists immediately tried to reproduce a similar cold fusion and they found largely inconsistent results. Many suggested that the heat Pons and Fleischman observed was produced either by the current or by reactions in the water.
Skeptical scientists immediately tried to reproduce a similar cold fusion and they found largely inconsistent results. Many suggested that the heat Pons and Fleischman observed was produced either by the current or by reactions in the water.
Even to this day, many scientists continue to pursue cold fusion as a viable energy alternative. Until someone disproves the process, it will remain elusive--maybe fact, maybe fiction. But the lesson remains: reputable, peer-reviewed scientific journals are a much more reliable medium than a press conference through which to share scientific results.
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