Cold fusion

As cold fusion refers to procedures designed to bring about a useful as an energy source, controlled nuclear fusion of hydrogen isotopes without a plasma must be produced with high temperature and density as in a nuclear fusion reactor or in inertial confinement fusion. A frequently used synonym for cold fusion is LENR ( low energy nuclear reactions ), so nuclear reactions at low energy.

Preliminary views on the merger at low temperatures, there was in the 1940s in the Soviet Union ( muon -catalyzed fusion). The term was known cold fusion (English coldfusion ) by 1989 imagined by chemists Stanley Pons and Martin Fleischmann experiment. They claimed to have carried out a cold fusion electrochemical route on a palladium electrode. This was briefly rise to the hope that a new, virtually inexhaustible ability to generate electricity and power supply had been found. However, the laboratory results of Pons and Fleischmann could not be confirmed by independent third parties. A commission set up by the Department of Energy of the United States came to the conclusion that we are dealing with pathological science. As a consequence, most scientists believe that a nuclear reaction with release of energy in this way can not be initiated.

• 2.1 Controversial nickel-hydrogen reaction

Proposed mechanisms function

Muon -catalyzed fusion

Considerations to put on the end of the 1940s, Frederick Charles Frank and Andrei Sakharov, the postulated based on theoretical approaches that muons could facilitate the introduction of fusion nuclear reactions in the manner of a catalyst. Sakharov in 1948 coined for it and the term " cold fusion ". Luis W. Alvarez, who in 1968 was awarded the Nobel Prize in physics, discovered in 1956 on the bubble chamber photographs unusual tracks. Along with Edward Teller, he came to the conclusion that muons were triggered nuclear fusion.

EA Wesman developed by the Estonian Academy of Sciences in 1967 to the conceptual model of a muon catalyzed fusion. This model uses a result from atomic physics, according to which the orbital radius of a muon is inversely proportional to the reduced mass of the nucleus and the muon around a nucleus. As a muon compared to an electron has a significantly higher mass, its orbital is much closer to the nucleus than one electron. In addition, since in the reduced mass also enters the mass of the nucleus, also results in a higher mass of the nucleus for a dense -lying orbital of the bound particle. Now meets a negatively charged muon on a DT molecule ( from a deuterium and a tritium atom ), it may happen that the muon displaces an electron from the molecular orbitals and forms a new molecular orbital. While the nuclei are approximately 200 times bound narrower than the original molecule by the close screening of the charge of the tritium nucleus by the muon. Therefore, it can relatively easily for nuclear fusion (merger) come a muonic helium atom 5 is caused by the muonic from the DT molecule. This decays with a probability of 99.4 % in a helium -4 atom, a muon and a neutron while energy is released:

The liberated muon can trigger the same response again and thus keep a fusion process a chain reaction, and running after this reaction. The muon acts like a chemical catalyst. With a probability of 0.6%, the muon but also remains on helium -4 atom liable ( engl. sticking ) and then no longer available for further fusion processes:

The entire cycle of Myoneneinfang until fusion occurs in about 10-9 s The short lifetime of the muon of about 2.2 microseconds thus limits the number of individual reactions catalyzed principle approximately 2000 After the muon decays according back. :

For the production of a muon with a particle accelerator around 3 GeV are required. A net energy by the bullet of muons produced in a deuterium -tritium gas mixture initially appeared possible. That this is not yet the case is due to the above-described second follow-up process, in which the muon sticks and thus can not catalyze further fusion reactions. Because of the second process is reduced in accordance with the laws of probability to the average number of catalyzed fusions. The result of this geometric series is. This lower number of mergers nurmehr 2.9 GeV fusion energy produced, so less than is necessary for the production of a new muon. Therefore, this process can be a statistical average of no useful energy gain, especially when the additional electrical energy is taken into account that is required for the preparation and to the basic operation of the particle accelerator.

Venedikt Petrovich Dschelepow found at the nuclear research institute in Dubna out that the number of muon catalyzed by mergers increases with increasing temperature. However, this would contradict the principle of cold fusion.

Metal catalytic fusion

Palladium has the highest absorbency of all elements hydrogen; it can bind to the 900 times its own volume at room temperature. In addition, palladium has catalytic properties. Therefore, many attempts to use palladium cold fusion.

Paneth (1926 )

The first report on the conversion of hydrogen into helium in conjunction with palladium is from the year 1926 by Fritz Paneth. During the heating of hydrogen-treated palladium preparations he made an unexplained amount of helium determined. The following year, they had recognized, however some sources of error. An example is the better permeability at increased temperature of the glass for helium. In a publication from 1927 Paneth therefore indicated together with other authors, the helium as a result of these causes.

" Cold Fusion" by Fleischmann and Pons

The term " cold fusion " has become popular due to an initially reported as a success test of Fleischmann and Pons. On March 23, 1989 Martin Fleischmann and Stanley Pons reported at a press conference of experiments in which they had observed cold fusion. These reports were received as a sensation, because then would release a simple way energy from heavy water. For a short time there were in the professional world the hope that this could be done as a practically inexhaustible source of energy available on a large scale.

In this experiment, the fusion of hydrogen isotopes protium, deuterium and tritium to have taken place on the surface of a palladium cathode during the electrolysis of an electrolyte. As evidence of cold fusion evidence of the resulting helium atoms, tritium and neutrons or gamma rays ( certain energy or frequency) as well as proof of excess heat production, which can not be explained by chemical processes apply.

Already on May 1, 1989 reported the physicist Steven Koonin, Nathan Lewis, and Charles Barnes from Caltech at a meeting of the American Physical Society fault of the Fleischmann -Pons experiments gradually disproved their results. Also other laboratories failed to confirm the Fleischmann -Pons results, even with orders of magnitude more sensitive measuring equipment. Fleischmann and Pons himself could not repeat their results in front of witnesses.

Meanwhile, global research had used. Thus, for example, in July 1989 by an Indian research group at the BARC (PK Iyengar and M. Srinivasan ) and in October 1989 by a US-based group ( Bockris et al. ) about the formation of tritium reported. In December 1990, Emeritus Professor Richard Oriani published at the University of Minnesota nor excess heat in cold fusion.

The U.S. government set up a commission of the Department of Energy a (DOE ), for an examination of the possible impact on the national energy supply. The DOE, the Commission concluded in November 1989 concluded that the current evidence for the discovery of a new nuclear physics process called " cold fusion ", were not convincing.

About the initially constructed within a few months of euphoria followed by disappointment was widely reported in the general media.

Republishing of Fleischmann helped that the DOE once again took the matter in the years after 2003. Despite the more advanced technology since 1989, the calorimetric measurement and carried out subsequent experiments, the DOE comes to the same conclusion as in 1989 and advises against a targeted promotion of research into the effects on the development of an alternative energy source described.

In November 2005, a much-noticed press release from the Technical University of Berlin, in which it is said appeared TU- scientists to the nuclear physicist Armin Huke had found in nuclear physics accelerator experiments first experimental evidence for the " miracle" of cold fusion. The Faculty of Physics distanced himself shortly afterwards and told them, at the TU Berlin there were no comprehensive work on cold fusion.

Ongoing scientific work

Some research groups around the world to this day continue or new scientific studies in the field of " cold fusion " or LENR by.

Science journalists prepare the topic occasionally or report about scientists who see potential in cold fusion. The American Physical Society makes regular symposia on LENR; the American Chemical Society did so after 1989, in 2007, again for the first time. In March 2012 it was reported at a conference of the American Nuclear Society (ANS ) on LENR. The U.S. military authority SPAWAR ( Space and Naval Warfare Systems Command ) leads since 1989 through experiments and has repeatedly been reported in peer-reviewed journals of their work.

The University of Missouri was awarded in 2012 by a private foundation research funds in the amount of $ 5.5 million to explore the emergence of excess heat in interactions between hydrogen and palladium, nickel or platinum.

Pyrofusion

Seth Putterman of the University of California and his colleagues Naranjo and Gimzewski published a work on pyroelectric induced nuclear fusion in Nature in 2005. Make it a comparatively small apparatus " on the bench " in front, allowing the mergers of deuterium nuclei. To ionize the deuterium atoms, and then to accelerate to the required speed for the fusion, the investigators used a pyroelectric crystal as a power source - hence the term Pyrofusion. The deuterium is ionized by the strong electric field at a tungsten tip and accelerates the ions. The neutron flux generated was at 400 times the natural neutron radiation. As a source of neutrons, the experimenters suggest the fusion of two deuterium nuclei to form helium, a free neutron is created:

Due to the inherently limited to small particle streams performance is yet no prospect of being able to release energy for practical purposes in this way. As a neutron source, such as for purposes of analysis, the structure is nevertheless appropriate.

Sonofusion

The U.S. scientists Rusi P. Taleyarkhan of Oak Ridge National Laboratory reported in March 2002 in the journal Science about the possibility of bringing about tripped by sound waves cavitation controlled fusion. In this Sonofusion or vesicle fusion procedure to said high temperatures, pressures, radiation and neutron densities occur which enable nuclear fusion.

A furnished at the instigation of the U.S. Navy commission of five universities came to the conclusion that experiments of another group that seemed to confirm the results were falsified. In August 2008, Taleyarkhan was deprived of his professorship at the University of Purdue due to unscientific behavior ( scientific misconduct ). Although he remains a member of the faculty, but under the name specialGraduate faculty and without the right to supervise doctoral students. The affair was known by the name bubble gate.

In Germany the Sonofusion was the core Technology Professor Günter Lohnert, University of Stuttgart, propagated; Lohnert, which also deals with pebble bed reactors, called the Sonofusion in 2005 as proven. Lohnert has also as editor of the journal Nuclear Engineering and Design (NED ) after a short examination, to consult without other reviewers, the aforementioned, now rated as forged work, which seemed to confirm the Sonofusion accepted. He gave the opportunity to present its position in NED during the U.S. examination procedure for Sonofusion Taleyarkhan 2007 and 2008. Lohnert was replaced in 2009 as an active publisher of NED.

Commercial use tests

Controversial nickel-hydrogen reaction

In early 2011 claimed the Italian entrepreneur Andrea Rossi, together with the physicist Sergio Focardi that he could fuse nickel and hydrogen to copper and thus produce an over longer time self-sustained exothermic reaction in a device that known as the " E-Cat " is. All 15 claims of a patent application of 2008, the property of an invention ( inventive step) were agreed by the European Patent Office in a report in 2010. Independent confirmation of the experiment are not yet available. The case of such fusion reactions actually expected gamma radiation was not observed. The for fall 2011 announced in Greece presentation of a functioning reactor was canceled. A thorough scan of the device does not allow Rossi. Several evaluators therefore refrained from a final judgment. The LENR blogger Krivit has gathered evidence that Rossi systematically the device manipulated to give the impression of a significant energy production.

Literary and film processing

• The novel The Cold Fusion by Johannes Schmidl plays with the possibility of a successful experiment on the model of Sonofusion.
• In the film Out of Control by Andrew Davis Sonofusionsidee is implemented on film.
• In the movie The Saint - The man with no name references a researcher on cold fusion.
• In the feature film I.Q. - Love is relative, which is set in the fifties, the fictional Albert Einstein used the theory to arouse the interest of his niece to a non- scientist. However, the Einstein in the film is aware that cold fusion " a hoax " is.
• The fictional technical application of muon -catalyzed fusion describes Arthur C. Clarke in his novel 2061 - Odyssey III.
• In his book Burned by Andreas Eschbach a minor character describes cold fusion as the best source of energy, which is, however, in their view, rejected by energy companies such as Shell, in order not to lose the energy monopoly. The procedure is otherwise presented as nonsense.
• The merger means of palladium is described in the thriller The Source by Uwe Schomburg.