Gravitational shielding

The term gravitational shielding refers to a hypothetical process of shielding an object from the influence of a gravitational field. Such processes, if they existed, would have the effect of reducing the weight of an object. The shape of the shielded region would be similar to a shadow from the gravitational shield. For example, the shape of the shielded region above a disk would be conical. The height of the cone's apex above the disk would vary directly with the height of the shielding disk above the Earth.[1] Experimental evidence to date indicates that no such effect exists. Gravitational shielding is considered to be a violation of the equivalence principle and therefore inconsistent with both Newtonian theory and general relativity.[2]

The concept of gravity shielding is a common concept in science fiction literature, especially for space travel. One of the first and best known examples is the fictional gravity shielding substance "Cavorite" that appears in H. G. Wells' classic 1901 novel The First Men in the Moon. Wells was promptly criticized for using it by Jules Verne.[3]

  1. ^ Unnikrishnan, C.S. (1996). "Does a superconductor shield gravity?". Physica C: Superconductivity. 266 (1–2). Elsevier BV: 133–137. Bibcode:1996PhyC..266..133U. doi:10.1016/0921-4534(96)00340-1.
  2. ^ Bertolami, Orfeu; Páramos, Jorge; Turyshev, Slava G. (2008). "General Theory of Relativity: Will It Survive the Next Decade?". Lasers, Clocks and Drag-Free Control. Astrophysics and Space Science Library. Vol. 349. pp. 27–74. doi:10.1007/978-3-540-34377-6_2. ISBN 978-3-540-34376-9. S2CID 12079261.
  3. ^ Giblin, James (2000). The Century that was: Reflections on the Last One Hundred Years. Simon and Schuster. p. 8. ISBN 978-0-689-82281-0. I sent my travelers to the moon with gunpowder, something one sees every day. Where is Monsieur Wells' 'Cavorite'? Let him show it to me!