Changes

The approach that has generally been taken is to heat the gaseous deuterium to such a high temperature that it becomes a [[plasma]] and that the nuclei have sufficient [[kinetic energy]] so that some of them can overcome their repulsion and collide.

The approach that has generally been taken is to heat the gaseous deuterium to such a high temperature that it becomes a [[plasma]] and that the nuclei have sufficient [[kinetic energy]] so that some of them can overcome their repulsion and collide.

However, the main problem of this approach is the containment of the high energy plasma. This may be achievable using precisely shaped [[magnetic field|magnetic fields]], but to date the longest period of stable fusion under this mechanism has been around half a second.

However, the main problem of this approach is the containment of the high energy plasma. This may be achievable using precisely shaped [[magnetic field]]s, but to date the longest period of stable fusion under this mechanism has been around half a second.

== Low Temperature Fusion ==

== Low Temperature Fusion ==

There is, however, no fundamental law that says that this high temperature approach is the only way to get the deuterium nuclei close enough to react, or that the only possible fusion reaction is between only two nuclei. Other approaches have been posited. For example, if the [[electrons]] of deuterium [[atoms]] could be persuaded to orbit much closer to the nucleus then the atom would have an overall neutral charge until it was in much closer proximity to another atom (i.e. until the nuclei were within the orbit of the electrons).

There is, however, no fundamental law that says that this high temperature approach is the only way to get the deuterium nuclei close enough to react, or that the only possible fusion reaction is between only two nuclei. Other approaches have been posited. For example, if the [[electrons]] of deuterium [[atoms]] could be persuaded to orbit much closer to the nucleus then the atom would have an overall neutral charge until it was in much closer proximity to another atom (i.e. until the nuclei were within the orbit of the electrons).

Quantum Theory indicates that this would be impossible with electrons, but it is known to occur with a [[muon]] instead of an electron. Since a muon is 207 times heavier than an electron it orbits 207 times closer. <ref>http://www.rikenresearch.riken.jp/eng/frontline/5976</ref>

Quantum Theory indicates that this would be impossible with electrons, but it is known to occur with a [[muon]] instead of an electron. Since a muon is 207 times heavier than an electron it orbits 207 times closer.<ref>http://www.rikenresearch.riken.jp/eng/frontline/5976</ref>

However, muon-catalyzed fusion requires the production of muons, which requires substantial energy, and while one muon may catalyze more than one fusion reaction, eventually the muons are captured by other nuclei, such as helium, and the muon cannot then cause more fusions. It is real, but far from practical for energy production, as far as any approach known.

However, muon-catalyzed fusion requires the production of muons, which requires substantial energy, and while one muon may catalyze more than one fusion reaction, eventually the muons are captured by other nuclei, such as helium, and the muon cannot then cause more fusions. It is real, but far from practical for energy production, as far as any approach known.

The field has expanded from deuterium in palladium to also include hydrogen in nickel and nickel nano-powder, low energy glow discharge, and transmutation experiments (mostly in Japan). Research funding sources in the US include the Defense Advanced Research Projects Administration (DARPA), and the Department of Defense, Threat Reduction Agency.  

The field has expanded from deuterium in palladium to also include hydrogen in nickel and nickel nano-powder, low energy glow discharge, and transmutation experiments (mostly in Japan). Research funding sources in the US include the Defense Advanced Research Projects Administration (DARPA), and the Department of Defense, Threat Reduction Agency.  

There are also companies claiming to have working Nickel-Hydrogen demonstration devices, claiming power levels that could see commercial usage; however there is no open independent evidence that these devices work reliably, only enthusiasm, promises from the companies -- often not met --, and some public demonstrations that convinced some, but that were also flawed in ways that eventually led to extended skepticism even from those who have accepted cold fusion in general.

There are also companies claiming to have working Nickel-Hydrogen demonstration devices, claiming power levels that could see commercial usage; however there is no open independent evidence that these devices work reliably, only enthusiasm, promises from the companies—often not met --, and some public demonstrations that convinced some, but that were also flawed in ways that eventually led to extended skepticism even from those who have accepted cold fusion in general.

The 17th International Conference on Cold Fusion was held in  Deajeon, Korea, August 12-17, 2012.

The 17th International Conference on Cold Fusion was held in  Deajeon, Korea, August 12–17, 2012.

=Recent coverage=

=Recent coverage=

*[http://www.popsci.com/category/tags/november-2012 Popular Science, November 2012]. "Can Andrea Rossi's Infinite-Energy Black Box Power The World--Or Just Scam It?" ''The Rossi claims have not been independently confirmed, and publicly-available evidence is inadequate to determine if the devices work at all, and if they do, if they depend on cold fusion, or low-energy nuclear reactions, or not. There is minor coverage in this article of other, scientifically-established, approaches to cold fusion. ''

*[http://www.popsci.com/category/tags/november-2012 Popular Science, November 2012]. "Can Andrea Rossi's Infinite-Energy Black Box Power The World--Or Just Scam It?" ''The Rossi claims have not been independently confirmed, and publicly-available evidence is inadequate to determine if the devices work at all, and if they do, if they depend on cold fusion, or low-energy nuclear reactions, or not. There is minor coverage in this article of other, scientifically-established, approaches to cold fusion. ''