Editing Anti-gravity (section)

===Gyroscopic devices===
[[File:H W Wallace force field figure 4.png|thumb|upright=1.5|A "kinemassic field" generator from {{US patent|3626605}}: Method and apparatus for generating a secondary gravitational force field]]
[[Gyroscope]]s produce a force when twisted that operates "out of plane" and can appear to lift themselves against gravity. Although this force is well understood to be illusory, even under Newtonian models, it has nevertheless generated numerous claims of anti-gravity devices and any number of patented devices. None of these devices has ever been demonstrated to work under controlled conditions, and they have often become the subject of [[conspiracy theories]] as a result.

Another "rotating device" example is shown in a series of patents granted to Henry Wallace between 1968 and 1974. His devices consist of rapidly spinning disks of [[brass]], a material made up largely of elements with a total half-integer nuclear spin. He claimed that by rapidly rotating a disk of such material, the [[nuclear spin]] became aligned, and as a result created a "gravitomagnetic" field in a fashion similar to the magnetic field created by the [[Barnett effect]].<ref>{{US patent|3626606}}</ref><ref>{{US patent|3626605}}</ref><ref>{{US patent|3823570}}</ref> No independent testing or public demonstration of these devices is known.

In 1989, it was reported that a weight decreases along the axis of a right spinning gyroscope.<ref>{{cite journal|author=Hayasaka, H.|author2=Takeuchi, S.|name-list-style=amp|date=1989|journal=[[Physical Review Letters]]|title=Anomalous weight reduction on a gyroscope's right rotations around the vertical axis on the Earth|volume=63|issue=25|pages=2701–2704|doi=10.1103/PhysRevLett.63.2701|pmid=10040968|bibcode=1989PhRvL..63.2701H}}</ref> A test of this claim a year later yielded null results.<ref>{{cite journal|author=Nitschke, J. M.|author2=Wilmath, P. A.|name-list-style=amp|title=Null result for the weight change of a spinning gyroscope|date=1990|journal=[[Physical Review Letters]]|volume=64| issue=18|pages=2115–2116|doi=10.1103/PhysRevLett.64.2115|pmid=10041587|bibcode = 1990PhRvL..64.2115N |url=https://zenodo.org/record/1233872}}</ref> A recommendation was made to conduct further tests at a 1999 AIP conference.<ref>{{cite conference |last=Iwanaga |first=N. |book-title=AIP Conference Proceedings |date=1999 |volume=458 |pages=1015–1059 |doi=10.1063/1.57497 |title=Reviews of some field propulsion methods from the general relativistic standpoint}}</ref>