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The Allais effect refers to the anomalous behavior of pendulums or gravimeters, which is sometimes observed during a solar eclipse. The effect was first reported as an anomalous precession of the plane of oscillation of a pendulum for the solar eclipse of June 30, 1954 by Maurice Allais, a French polymath who went on to win the Nobel Prize in Economics. He reported another observation of the effect during the solar eclipse of October 2, 1959. ==Experimental observations== Various experiments have been performed in order to detect anomalous behavior during solar eclipses. Some observations gave positive results and some failed to detect any noticeable effect. The table below gives an overview of the different experiments. A published observation of what was initially claimed to be a possibly related anomalous gravitational effect (claimed variation of terrestrial gravitation as measured by a sensitive gravimeter) was by Wang ''et al.'' in 2000, for an experiment carried out in 1997 in a remote region of China during a total solar eclipse. Further observations which the same team performed in 2001 and 2002 during solar eclipses in Zambia and Australia appear to have yielded much weaker evidence of similar anomalies. However, the same authors later (2002 and 2003) published papers explaining that their observations could be explained by conventional phenomena such as temperature and pressure change caused by the eclipse. In their 2002 paper, they posited a more conventional explanation based on temperature changes causing ground tilting, but they suggested that this explanation was unlikely. In their 2003 paper (Flandern and Yang, 2003), on the other hand, the authors argued that atmospheric motion induced by temperature changes was both plausible and sufficient to explain the observed anomaly. A published article on the topic in a mainstream scientific journal (Flandern, 2003) concludes that there have been "no unambiguous detections A possible but yet controversial explanation is the so-called van Flandern–Yang hypothesis by van Flandern and Yang's article,〔T. van Flandern and X. S. Yang, "Allais gravity and pendulum effects during solar eclipses explained," Phys. Rev. D 67, 022002 (2003).〕 which conjecture the effect is due to the gravitational effect of an increased density spot in the upper atmosphere created by cooling during the solar eclipse. A self-published review article by Chris Duif, which surveys the field of gravitational anomalies in general, concludes that the question remains open, and that such investigations should be pursued, in view of their relatively inexpensive nature and the enormous implications if genuine anomalies are actually confirmed – but the article has not undergone any peer review. During the solar eclipse of January 26, 2009, a correlation was found between anomalous behavior of a pendulum and torsion balances, located at two different points outside the shadow zone.〔A. F. Pugach and D. Olenici, “Observations of Correlated Behavior of Two Light Torsion Balances and a Paraconical Pendulum in Separate Locations during the Solar Eclipse of January 26th, 2009,” Advances in Astronomy, vol. 2012, Article ID 263818, 6 pages, 2012. doi:10.1155/2012/263818 http://www.hindawi.com/journals/aa/2012/263818/cta/〕 Eight gravimeters and two pendulums were deployed across six monitoring sites in China for the solar eclipse of July 22, 2009.〔"July eclipse is best chance to look for gravity anomaly", New Scientist, 2009-07-19 http://www.newscientist.com/article/dn17481-july-eclipse-is-best-chance-to-look-for-gravity-anomaly.html〕 Although one of the scientists involved claimed in an interview to have observed an Allais effect,〔"Eclipse at Sheshan Hill", The Atlantic, 2009–07 http://www.theatlantic.com/magazine/archive/2009/07/eclipse-at-sheshan-hill/7599/〕 the result has not been published in any mainstream peer-reviewed scientific journal. An automated Foucault pendulum was used by H.R. Salva and found no evidence for a precession change of the pendulum's oscillation plane (<0.3 degree / hour) during the Solar eclipse of July 11, 2010.〔H.R. Salva, ''Searching the Allais effect during the total sun eclipse of 11 July 2010'', Phys. Rev. D 83, 067302 (2011), http://dx.doi.org/10.1103/PhysRevD.83.067302〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Allais effect」の詳細全文を読む スポンサード リンク
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