Anti-gravity (also known as non-gravitational field) is a hypothetical phenomenon of creating a place or object that is free from the force of

gravity In physics, gravity () is a fundamental interaction which causes mutual attraction between all things with mass or energy. Gravity is, by far, the weakest of the four fundamental interactions, approximately 1038 times weaker than the stro ...

. It does not refer to the lack of weight under gravity experienced in

free fall In Newtonian physics, free fall is any motion of a body where gravity is the only force acting upon it. In the context of general relativity, where gravitation is reduced to a space-time curvature, a body in free fall has no force acting on i ...

orbit In celestial mechanics, an orbit is the curved trajectory of an object such as the trajectory of a planet around a star, or of a natural satellite around a planet, or of an artificial satellite around an object or position in space such as a p ...

, or to balancing the force of gravity with some other force, such as electromagnetism or aerodynamic lift. Anti-gravity is a recurring concept in science fiction. Examples are the gravity blocking substance "Cavorite" in

H. G. Wells Herbert George Wells"Wells, H. G."
Revised 18 May 2015. ''

The First Men in the Moon ''The First Men in the Moon'' is a scientific romance by the English author H. G. Wells, originally serialised in '' The Strand Magazine'' from December 1900 to August 1901 and published in hardcover in 1901, who called it one of his "fantast ...

'' and the

Spindizzy ''Cities in Flight'' is a four-volume series of science fiction novels and short stories by American writer James Blish, originally published between 1950 and 1962, which were first known collectively as the "Okie" novels. The series features ent ...

machines in James Blish's ''

Cities in Flight ''Cities in Flight'' is a four-volume series of science fiction novels and short stories by American writer James Blish, originally published between 1950 and 1962, which were first known collectively as the "Okie" novels. The series features ent ...

''. "Anti-gravity" is often used to refer to devices that look as if they reverse gravity even though they operate through other means, such as lifters, which fly in the air by moving air with

electromagnetic field An electromagnetic field (also EM field or EMF) is a classical (i.e. non-quantum) field produced by (stationary or moving) electric charges. It is the field described by classical electrodynamics (a classical field theory) and is the classical c ...

Historical attempts at understanding gravity

The possibility of creating anti-gravity depends upon a complete understanding and description of gravity and its interactions with other physical theories, such as

general relativity General relativity, also known as the general theory of relativity and Einstein's theory of gravity, is the geometric theory of gravitation published by Albert Einstein in 1915 and is the current description of gravitation in modern physics ...

and

quantum mechanics Quantum mechanics is a fundamental theory in physics that provides a description of the physical properties of nature at the scale of atoms and subatomic particles. It is the foundation of all quantum physics including quantum chemistry, ...

; as of 2022 physicists have yet to discover a quantum theory of gravity. During the summer of 1666,

Isaac Newton Sir Isaac Newton (25 December 1642 – 20 March 1726/27) was an English mathematician, physicist, astronomer, alchemist, theologian, and author (described in his time as a "natural philosopher"), widely recognised as one of the grea ...

observed an apple (variety '' Flower of Kent'') falling from the tree in his garden, thus realizing the principle of universal gravitation.Department of Physic
A Brief History of Isaac Newton's Apple Tree

University of York , mottoeng = On the threshold of wisdom , established = , type = Public research university , endowment = £8.0 million , budget = £403.6 million , chancellor = Heather Melville , vice_chancellor = Charlie Jeffery , students ...

, Retrieved 2019-07-20

Albert Einstein Albert Einstein ( ; ; 14 March 1879 – 18 April 1955) was a German-born theoretical physicist, widely acknowledged to be one of the greatest and most influential physicists of all time. Einstein is best known for developing the theory ...

in 1915 considered the physical interaction between matter and space, where gravity occurs as a consequence of matter causing a geometric deformation of space which is otherwise flat. Einstein, both independently and with

Walther Mayer Walther Mayer (11 March 1887 – 10 September 1948) was an Austrian mathematician, born in Graz, Austria-Hungary. With Leopold Vietoris he is the namesake of the Mayer–Vietoris sequence in topology.. He served as an assistant to Albert Einstei ...

, attempted to unify his

theory of gravity In physics, gravity () is a fundamental interaction which causes mutual attraction between all things with mass or energy. Gravity is, by far, the weakest of the four fundamental interactions, approximately 1038 times weaker than the stron ...

with

electromagnetism In physics, electromagnetism is an interaction that occurs between particles with electric charge. It is the second-strongest of the four fundamental interactions, after the strong force, and it is the dominant force in the interactions of a ...

using the work of

Theodor Kaluza Theodor Franz Eduard Kaluza (; 9 November 1885 – 19 January 1954) was a German mathematician and physicist known for the Kaluza–Klein theory, involving field equations in five-dimensional space-time. His idea that fundamental forces can be ...

and

James Clerk Maxwell James Clerk Maxwell (13 June 1831 – 5 November 1879) was a Scottish mathematician and scientist responsible for the classical theory of electromagnetic radiation, which was the first theory to describe electricity, magnetism and ligh ...

to link gravity and

quantum field theory In theoretical physics, quantum field theory (QFT) is a theoretical framework that combines classical field theory, special relativity, and quantum mechanics. QFT is used in particle physics to construct physical models of subatomic particles and ...

. Theoretical quantum physicists have postulated the existence of a quantum gravity particle, the

graviton In theories of quantum gravity, the graviton is the hypothetical quantum of gravity, an elementary particle that mediates the force of gravitational interaction. There is no complete quantum field theory of gravitons due to an outstanding mathem ...

. Various theoretical explanations of

quantum gravity Quantum gravity (QG) is a field of theoretical physics that seeks to describe gravity according to the principles of quantum mechanics; it deals with environments in which neither gravitational nor quantum effects can be ignored, such as in the vi ...

have been created, these include

superstring theory Superstring theory is an attempt to explain all of the particles and fundamental forces of nature in one theory by modeling them as vibrations of tiny supersymmetric strings. 'Superstring theory' is a shorthand for supersymmetric string theor ...

loop quantum gravity Loop quantum gravity (LQG) is a theory of quantum gravity, which aims to merge quantum mechanics and general relativity, incorporating matter of the Standard Model into the framework established for the pure quantum gravity case. It is an attem ...

E8 theory "An Exceptionally Simple Theory of Everything" is a physics preprint proposing a basis for a unified field theory, often referred to as "E8 Theory", which attempts to describe all known fundamental interactions in physics and to stand as a possibl ...

and asymptotic safety theory amongst many others.

Hypothetical solutions

Newton's law of universal gravitation Newton's law of universal gravitation is usually stated as that every particle attracts every other particle in the universe with a force that is proportional to the product of their masses and inversely proportional to the square of the distanc ...

, gravity was an external force transmitted by unknown means. In the 20th century, Newton's model was replaced by

where gravity is not a force but the result of the geometry of spacetime. Under general relativity, anti-gravity is impossible except under contrived circumstances.

Gravity shields

In 1948 businessman

Roger Babson Roger Ward Babson (July 6, 1875 – March 5, 1967) was an American entrepreneur, economist, and business theorist in the first half of the 20th century. He is best remembered for founding Babson College. He also founded Webber College, now Webb ...

(founder of

Babson College Babson College is a private business school in Wellesley, Massachusetts. Established in 1919, its central focus is on entrepreneurship education. It was founded by Roger W. Babson as an all-male business institute, but became coeducational i ...

) formed the

Gravity Research Foundation The Gravity Research Foundation is an organization established in 1948 by businessman Roger Babson (founder of Babson College) to find ways to implement gravitational shielding. Over time, the foundation turned away from trying to block gravity ...

to study ways to reduce the effects of gravity. Their efforts were initially somewhat " crankish", but they held occasional conferences that drew such people as

Clarence Birdseye Clarence Birdseye (December 9, 1886 – October 7, 1956) was an American inventor, entrepreneur, and naturalist, considered the founder of the modern frozen food industry. He founded the frozen food company Birds Eye. Among his inventions during ...

, known for his frozen-food products, and helicopter pioneer

Igor Sikorsky Igor Ivanovich Sikorsky (russian: И́горь Ива́нович Сико́рский, p=ˈiɡərʲ ɪˈvanəvitʃ sʲɪˈkorskʲɪj, a=Ru-Igor Sikorsky.ogg, tr. ''Ígor' Ivánovich Sikórskiy''; May 25, 1889 – October 26, 1972)Fortie ...

. Over time the Foundation turned its attention away from trying to control gravity, to simply better understanding it. The Foundation nearly disappeared after Babson's death in 1967. However, it continues to run an essay award, offering prizes of up to $4,000. As of 2017, it is still administered out of

Wellesley, Massachusetts Wellesley () is a New England town, town in Norfolk County, Massachusetts, Norfolk County, Massachusetts, United States. Wellesley is part of Greater Boston. The population was 29,550 at the time of the 2020 census. Wellesley College, Babson Col ...

, by George Rideout Jr., son of the foundation's original director. Winners include California astrophysicist

George F. Smoot George Fitzgerald Smoot III (born February 20, 1945) is an American astrophysics, astrophysicist, cosmology, cosmologist, Nobel laureate, and the 2nd contestant to win the $1 million prize on ''Are You Smarter than a 5th Grader? (U.S. game show ...

(1993), who later won the 2006

Nobel Prize in physics ) , image = Nobel Prize.png , alt = A golden medallion with an embossed image of a bearded man facing left in profile. To the left of the man is the text "ALFR•" then "NOBEL", and on the right, the text (smaller) "NAT•" then " ...

, and

Gerard 't Hooft Gerardus (Gerard) 't Hooft (; born July 5, 1946) is a Dutch theoretical physicist and professor at Utrecht University, the Netherlands. He shared the 1999 Nobel Prize in Physics with his thesis advisor Martinus J. G. Veltman "for elucidating th ...

(2015) who previously won the 1999 Nobel Prize in physics.

General relativity research in the 1950s

General relativity was introduced in the 1910s, but development of the theory was greatly slowed by a lack of suitable mathematical tools. It appeared that anti-gravity was outlawed under general relativity. It is claimed the

US Air Force The United States Air Force (USAF) is the air service branch of the United States Armed Forces, and is one of the eight uniformed services of the United States. Originally created on 1 August 1907, as a part of the United States Army Signal ...

also ran a study effort throughout the 1950s and into the 1960s. Former Lieutenant Colonel

Ansel Talbert Ansel Edward McLaurine Talbert (6 January 1912 – 7 October 1987) was an American aviation journalist. After being named as a Communist by journalist Winston Burdett, Talbert became well known for his testimony before the United States Senate Sub ...

wrote two series of newspaper articles claiming that most of the major aviation firms had started gravity control propulsion research in the 1950s. However, there is little outside confirmation of these stories, and since they take place in the midst of the

policy by press release Policy by press release refers to the act of attempting to influence public policy by press releases intended to alarm the public into demanding action from their elected officials. In modern times, the term is used to dismiss an opponent's claims ...

era, it is not clear how much weight these stories should be given. It is known that there were serious efforts underway at the Glenn L. Martin Company, who formed the Research Institute for Advanced Study. Major newspapers announced the contract that had been made between theoretical physicist

Burkhard Heim Burkhard Heim (; 9 February 1925 – 14 January 2001) was a German theoretical physicist. He devoted a large portion of his life to the pursuit of his unified field theory, Heim theory. One of his childhood ambitions was to develop a method of s ...

and the Glenn L. Martin Company. Another effort in the private sector to master understanding of gravitation was the creation of the Institute for Field Physics,

University of North Carolina at Chapel Hill A university () is an institution of higher (or tertiary) education and research which awards academic degrees in several academic disciplines. Universities typically offer both undergraduate and postgraduate programs. In the United States ...

in 1956, by Gravity Research Foundation trustee Agnew H. Bahnson. Military support for anti-gravity projects was terminated by the

Mansfield Amendment Michael Joseph Mansfield (March 16, 1903 – October 5, 2001) was an American politician and diplomat. A Democrat, he served as a U.S. representative (1943–1953) and a U.S. senator (1953–1977) from Montana. He was the longest-serving Sena ...

of 1973, which restricted

Department of Defense Department of Defence or Department of Defense may refer to: Current departments of defence * Department of Defence (Australia) * Department of National Defence (Canada) * Department of Defence (Ireland) * Department of National Defense (Philipp ...

spending to only the areas of scientific research with explicit military applications. The Mansfield Amendment was passed specifically to end long-running projects that had little to show for their efforts. Under general relativity, gravity is the result of following spatial geometry (change in the normal shape of space) caused by local mass-energy. This theory holds that it is the altered shape of space, deformed by massive objects, that causes gravity, which is actually a property of deformed space rather than being a true force. Although the equations cannot normally produce a "negative geometry", it is possible to do so by using "

negative mass In theoretical physics, negative mass is a type of exotic matter whose mass is of opposite sign to the mass of normal matter, e.g. −1 kg. Such matter would violate one or more energy conditions and show some strange properties such as the ...

". The same equations do not, of themselves, rule out the existence of negative mass. Both general relativity and Newtonian gravity appear to predict that negative mass would produce a repulsive gravitational field. In particular, Sir

Hermann Bondi Sir Hermann Bondi (1 November 1919 – 10 September 2005) was an Austrian- British mathematician and cosmologist. He is best known for developing the steady state model of the universe with Fred Hoyle and Thomas Gold as an alternative to the ...

proposed in 1957 that negative gravitational mass, combined with negative inertial mass, would comply with the

strong equivalence principle In the theory of general relativity, the equivalence principle is the equivalence of gravitational and inertial mass, and Albert Einstein's observation that the gravitational "force" as experienced locally while standing on a massive body (suc ...

of general relativity theory and the Newtonian laws of conservation of linear momentum and energy. Bondi's proof yielded singularity-free solutions for the relativity equations. In July 1988,

Robert L. Forward Robert Lull Forward (August 15, 1932 – September 21, 2002) was an American physicist and science fiction writer. His literary work was noted for its scientific credibility and use of ideas developed from his career as an aerospace engineer. He ...

presented a paper at the AIAA/ASME/SAE/ASEE 24th Joint Propulsion Conference that proposed a Bondi negative gravitational mass propulsion system.; see also commentary Bondi pointed out that a negative mass will fall toward (and not away from) "normal" matter, since although the gravitational force is repulsive, the negative mass (according to Newton's law, F=ma) responds by accelerating in the opposite of the direction of the force. Normal mass, on the other hand, will fall away from the negative matter. He noted that two identical masses, one positive and one negative, placed near each other will therefore self-accelerate in the direction of the line between them, with the negative mass chasing after the positive mass. Notice that because the negative mass acquires negative

kinetic energy In physics, the kinetic energy of an object is the energy that it possesses due to its motion. It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity. Having gained this energy during its accele ...

, the total energy of the accelerating masses remains at zero. Forward pointed out that the self-acceleration effect is due to the negative inertial mass, and could be seen induced without the gravitational forces between the particles. The

Standard Model The Standard Model of particle physics is the theory describing three of the four known fundamental forces (electromagnetism, electromagnetic, weak interaction, weak and strong interactions - excluding gravity) in the universe and classifying a ...

of particle physics, which describes all currently known forms of matter, does not include negative mass. Although cosmological

dark matter Dark matter is a hypothetical form of matter thought to account for approximately 85% of the matter in the universe. Dark matter is called "dark" because it does not appear to interact with the electromagnetic field, which means it does not ab ...

may consist of particles outside the Standard Model whose nature is unknown, their mass is ostensibly known – since they were postulated from their gravitational effects on surrounding objects, which implies their mass is positive. The proposed cosmological

dark energy In physical cosmology and astronomy, dark energy is an unknown form of energy that affects the universe on the largest scales. The first observational evidence for its existence came from measurements of supernovas, which showed that the univer ...

, on the other hand, is more complicated, since according to general relativity the effects of both its energy density and its negative pressure contribute to its gravitational effect.

Unique force

Under general relativity any form of energy couples with spacetime to create the geometries that cause gravity. A longstanding question was whether or not these same equations applied to

antimatter In modern physics, antimatter is defined as matter composed of the antiparticles (or "partners") of the corresponding particles in "ordinary" matter. Antimatter occurs in natural processes like cosmic ray collisions and some types of radioac ...

. The issue was considered solved in 1960 with the development of

CPT symmetry Charge, parity, and time reversal symmetry is a fundamental symmetry of physical laws under the simultaneous transformations of charge conjugation (C), parity transformation (P), and time reversal (T). CPT is the only combination of C, P, and T ...

, which demonstrated that antimatter follows the same laws of physics as "normal" matter, and therefore has positive energy content and also causes (and reacts to) gravity like normal matter (see

gravitational interaction of antimatter The gravitational interaction of antimatter with matter or antimatter has not been observed by physicists. While the consensus among physicists is that gravity is expected to attract both matter and antimatter at the same rate that matter attra ...

). For much of the last quarter of the 20th century, the physics community was involved in attempts to produce a

unified field theory In physics, a unified field theory (UFT) is a type of field theory that allows all that is usually thought of as fundamental forces and elementary particles to be written in terms of a pair of physical and virtual fields. According to the modern ...

, a single physical theory that explains the four fundamental forces: gravity, electromagnetism, and the strong and weak nuclear forces. Scientists have made progress in unifying the three quantum forces, but gravity has remained "the problem" in every attempt. This has not stopped any number of such attempts from being made, however. Generally these attempts tried to "quantize gravity" by positing a particle, the

, that carried gravity in the same way that

photon A photon () is an elementary particle that is a quantum of the electromagnetic field, including electromagnetic radiation such as light and radio waves, and the force carrier for the electromagnetic force. Photons are massless, so they always ...

s (light) carry electromagnetism. Simple attempts along this direction all failed, however, leading to more complex examples that attempted to account for these problems. Two of these,

supersymmetry In a supersymmetric theory the equations for force and the equations for matter are identical. In theoretical and mathematical physics, any theory with this property has the principle of supersymmetry (SUSY). Dozens of supersymmetric theories e ...

and the relativity related

supergravity In theoretical physics, supergravity (supergravity theory; SUGRA for short) is a modern field theory that combines the principles of supersymmetry and general relativity; this is in contrast to non-gravitational supersymmetric theories such as ...

, both required the existence of an extremely weak "fifth force" carried by a

graviphoton In theoretical physics and quantum physics, a graviphoton or gravivector is a hypothetical particle which emerges as an excitation of the metric tensor (i.e. gravitational field) in spacetime dimensions higher than four, as described in Kaluza– ...

, which coupled together several "loose ends" in quantum field theory, in an organized manner. As a side effect, both theories also all but required that antimatter be affected by this fifth force in a way similar to anti-gravity, dictating repulsion away from mass. Several experiments were carried out in the 1990s to measure this effect, but none yielded positive results.''Supergravity and the Unification of the Laws of Physics,'' by

Daniel Z. Freedman Daniel Zissel Freedman (born 1939 in Hartford, Connecticut) is an American theoretical physicist. He is an Emeritus Professor of Physics and Applied Mathematics at the Massachusetts Institute of Technology (MIT), and is currently a visiting profe ...

and Peter van Nieuwenhuizen, Scientific American, February 1978 In 2013

CERN The European Organization for Nuclear Research, known as CERN (; ; ), is an intergovernmental organization that operates the largest particle physics laboratory in the world. Established in 1954, it is based in a northwestern suburb of Gene ...

looked for an antigravity effect in an experiment designed to study the energy levels within antihydrogen. The antigravity measurement was just an "interesting sideshow" and was inconclusive.

Breakthrough Propulsion Physics Program

During the close of the twentieth century

NASA The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeeding t ...

provided funding for the

Breakthrough Propulsion Physics Program The Breakthrough Propulsion Physics Project (BPP) was a research project funded by NASA from 1996-2002 to study various proposals for revolutionary methods of spacecraft propulsion that would require breakthroughs in physics before they could be re ...

(BPP) from 1996 through 2002. This program studied a number of "far out" designs for space propulsion that were not receiving funding through normal university or commercial channels. Anti-gravity-like concepts were investigated under the name "diametric drive". The work of the BPP program continues in the independent, non-NASA affiliated

Tau Zero Foundation The Breakthrough Propulsion Physics Project (BPP) was a research project funded by NASA from 1996-2002 to study various proposals for revolutionary methods of spacecraft propulsion that would require breakthroughs in physics before they could be r ...

Empirical claims and commercial efforts

There have been a number of attempts to build anti-gravity devices, and a small number of reports of anti-gravity-like effects in the scientific literature. None of the examples that follow are accepted as reproducible examples of anti-gravity.

Gyroscopic devices

Gyroscope A gyroscope (from Ancient Greek γῦρος ''gŷros'', "round" and σκοπέω ''skopéō'', "to look") is a device used for measuring or maintaining orientation and angular velocity. It is a spinning wheel or disc in which the axis of rota ...

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 have ever been demonstrated to work under controlled conditions, and have often become the subject of

conspiracy theories A conspiracy theory is an explanation for an event or situation that invokes a conspiracy by sinister and powerful groups, often political in motivation, when other explanations are more probable.Additional sources: * * * * The term has a nega ...

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 Brass is an alloy of copper (Cu) and zinc (Zn), in proportions which can be varied to achieve different mechanical, electrical, and chemical properties. It is a substitutional alloy: atoms of the two constituents may replace each other with ...

, 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 The Barnett effect is the magnetization of an uncharged body when spun on its axis. It was discovered by American physicist Samuel Barnett in 1915. An uncharged object rotating with angular velocity tends to spontaneously magnetize, with a magn ...

. 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. A test of this claim a year later yielded null results. A recommendation was made to conduct further tests at a 1999 AIP conference.

Thomas Townsend Brown's gravitator

In 1921, while still in

high school A secondary school describes an institution that provides secondary education and also usually includes the building where this takes place. Some secondary schools provide both '' lower secondary education'' (ages 11 to 14) and ''upper seconda ...

Thomas Townsend Brown Thomas Townsend Brown (March 18, 1905 – October 27, 1985) was an American inventor whose research into odd electrical effects led him to believe he had discovered a connection between strong electric fields and gravity, a type of antigravity ...

found that a high-voltage Coolidge tube seemed to change mass depending on its orientation on a balance scale. Through the 1920s Brown developed this into devices that combined high voltages with materials with high

dielectric In electromagnetism, a dielectric (or dielectric medium) is an electrical insulator that can be polarised by an applied electric field. When a dielectric material is placed in an electric field, electric charges do not flow through the mate ...

constants (essentially large capacitors); he called such a device a "gravitator". Brown made the claim to observers and in the media that his experiments were showing anti-gravity effects. Brown would continue his work and produced a series of high-voltage devices in the following years in attempts to sell his ideas to aircraft companies and the military. He coined the names Biefeld–Brown effect and

electrogravitics Electrogravitics is claimed to be an unconventional type of effect or anti-gravity force created by an electric field's effect on a mass. The name was coined in the 1920s by the discoverer of the effect, Thomas Townsend Brown, who spent most of h ...

in conjunction with his devices. Brown tested his asymmetrical capacitor devices in a vacuum, supposedly showing it was not a more down-to-earth electrohydrodynamic effect generated by high voltage ion flow in air. Electrogravitics is a popular topic in

ufology Ufology ( ) is the investigation of unidentified flying objects (UFOs) by people who believe that they may be of extraordinary origins (most frequently of extraterrestrial alien visitors). While there are instances of government, private, and f ...

, anti-gravity, free energy, with government conspiracy theorists and related websites, in books and publications with claims that the technology became highly classified in the early 1960s and that it is used to power UFOs and the

B-2 bomber The Northrop (later Northrop Grumman) B-2 Spirit, also known as the Stealth Bomber, is an American heavy strategic bomber, featuring low-observable stealth technology designed to penetrate dense anti-aircraft defenses. A subsonic flying ...

. There is also research and videos on the internet purported to show lifter-style capacitor devices working in a vacuum, therefore not receiving propulsion from ion drift or ion wind being generated in air. Follow-up studies on Brown's work and other claims have been conducted by R. L. Talley in a 1990 US Air Force study, NASA scientist Jonathan Campbell in a 2003 experiment, and Martin Tajmar in a 2004 paper. They have found that no thrust could be observed in a vacuum and that Brown's and other ion lifter devices produce thrust along their axis regardless of the direction of gravity consistent with electrohydrodynamic effects.

Gravitoelectric coupling

In 1992, the Russian researcher

Eugene Podkletnov Eugene Podkletnov (russian: Евгений Подклетнов, Yevgeny Podkletnov) is a Rossiyane, Russian Ceramic engineering, ceramics engineer known for his claims made in the 1990s of designing and demonstrating gravity shielding devices cons ...

claimed to have discovered, whilst experimenting with superconductors, that a fast rotating superconductor reduces the gravitational effect. Many studies have attempted to reproduce Podkletnov's experiment, always to negative results. Ning Li and Douglas Torr, of the

University of Alabama in Huntsville The University of Alabama in Huntsville (UAH) is a public research university in Huntsville, Alabama. The university is accredited by the Southern Association of Colleges and Schools and comprises nine colleges: arts, humanities & social science ...

proposed how a time dependent magnetic field could cause the spins of the lattice ions in a superconductor to generate detectable

gravitomagnetic Gravitoelectromagnetism, abbreviated GEM, refers to a set of formal analogies between the equations for electromagnetism and relativistic gravitation; specifically: between Maxwell's field equations and an approximation, valid under certain c ...

and gravitoelectric fields in a series of papers published between 1991 and 1993. In 1999, Li and her team appeared in ''

Popular Mechanics ''Popular Mechanics'' (sometimes PM or PopMech) is a magazine of popular science and technology, featuring automotive, home, outdoor, electronics, science, do-it-yourself, and technology topics. Military topics, aviation and transportation o ...

'', claiming to have constructed a working

prototype A prototype is an early sample, model, or release of a product built to test a concept or process. It is a term used in a variety of contexts, including semantics, design, electronics, and Software prototyping, software programming. A prototyp ...

to generate what she described as "AC Gravity." No further evidence of this prototype has been offered. Douglas Torr and

Timir Datta Timir Datta is an Indian-American physicist specializing in high transition temperature superconductors and a professor of physics in the department of Physics and Astronomy at the University of South Carolina, in Columbia, South Carolina. Earl ...

were involved in the development of a "gravity generator" at the University of South Carolina. According to a leaked document from the Office of Technology Transfer at the University of South Carolina and confirmed to ''Wired'' reporter Charles Platt in 1998, the device would create a "force beam" in any desired direction and that the university planned to patent and license this device. No further information about this university research project or the "Gravity Generator" device was ever made public.

Göde Award

The Institute for Gravity Research of the Göde Scientific Foundation has tried to reproduce many of the different experiments which claim any "anti-gravity" effects. All attempts by this group to observe an anti-gravity effect by reproducing past experiments have been unsuccessful thus far. The foundation has offered a reward of one million euros for a reproducible anti-gravity experiment.

In fiction

The existence of anti-gravity is a common theme in

fantasy Fantasy is a genre of speculative fiction involving Magic (supernatural), magical elements, typically set in a fictional universe and sometimes inspired by mythology and folklore. Its roots are in oral traditions, which then became fantasy ...

and

science fiction Science fiction (sometimes shortened to Sci-Fi or SF) is a genre of speculative fiction which typically deals with imaginative and futuristic concepts such as advanced science and technology, space exploration, time travel, parallel unive ...

Apergy

Apergy is a fictitious form of anti-gravitational energy first described by

Percy Greg Percy Greg (7 January 1836 Bury – 24 December 1889, Chelsea), son of William Rathbone Greg, was an English writer. Percy Greg, like his father, wrote about politics, but his views were violently reactionary: his ''History of the United States ...

in his 1880

sword and planet Sword and planet is a subgenre of science fantasy that features rousing adventure stories set on other planets, and usually featuring humans as protagonists. The name derives from the heroes of the genre engaging their adversaries in hand-to-ha ...

novel ''

Across the Zodiac ''Across the Zodiac: The Story of a Wrecked Record'' (1880) is a science fiction novel by Percy Greg, who has been credited as an originator of the sword and planet subgenre of science fiction. Plot The book details the creation and use of a ...

''. It is also used by

John Jacob Astor IV John Jacob Astor IV (July 13, 1864 – April 15, 1912) was an American business magnate, real estate developer, investor, writer, lieutenant colonel in the Spanish–American War, and a prominent member of the Astor family. He died in the sink ...

in his 1894 science fiction novel, ''

A Journey in Other Worlds ''A Journey in Other Worlds: A Romance of the Future'' is a science fiction novel by John Jacob Astor IV, published in 1894. Overview The book offers a fictional account of life in the year 2000. It contains abundant speculation about technolog ...

''. Apergy can also be found in an 1896 article by Clara Jessup Bloomfield-Moore, called "Some Truths About Keely". In it, apergy is used to describe the

latent Latency or latent may refer to: Science and technology * Latent heat, energy released or absorbed, by a body or a thermodynamic system, during a constant-temperature process * Latent variable, a variable that is not directly observed but inferred ...

force John Keely harnessed, by using frequency to release the latent force found within all atomic

matter In classical physics and general chemistry, matter is any substance that has mass and takes up space by having volume. All everyday objects that can be touched are ultimately composed of atoms, which are made up of interacting subatomic partic ...

. In an 1897, ostensibly non-fictitious, article in ''

The San Francisco Call ''The San Francisco Call'' was a newspaper that served San Francisco, California. Because of a succession of mergers with other newspapers, the paper variously came to be called ''The San Francisco Call & Post'', the ''San Francisco Call-Bulletin ...

'' titled "The Secret of Aerial Flight Revealed", science correspondent Frank M. Close, D. Sc., visits an unnamed Hindu man masquerading as a

viticulturist Viticulture (from the Latin word for ''vine'') or winegrowing (wine growing) is the cultivation and harvesting of grapes. It is a branch of the science of horticulture. While the native territory of ''Vitis vinifera'', the common grape vine, ran ...

somewhere on the

Pacific coast Pacific coast may be used to reference any coastline that borders the Pacific Ocean. Geography Americas Countries on the western side of the Americas have a Pacific coast as their western or southwestern border, except for Panama, where the Pac ...

who claims to have invented a flying boat that uses an "apergent"—a rare metal called "radlum"—to produce controlled apergic force, allowing the vessel to ascend and descend. The inventor describes apergy as "a force obtained by blending positive and negative electricity with ultheic, the third element or state of electric energy" and calls apergy a "second phase of gravity", hinting at a third phase as well. In

S. P. Meek Sterner St. Paul Meek (April 8, 1894 in Chicago, Illinois – June 10, 1972) was an American military chemist, early science fiction author, and children's author. He published much of his work first as Capt. S.P. Meek, then, briefly, as Major ...

's short story "Cold Light", which appeared in ''Astounding Stories of Super-Science'', March 1930, apergy is mentioned as the opposite force of gravity. In Chris Roberson's short story "Annus Mirabilis" from the 2006 second volume of ''

Tales of the Shadowmen ''Tales of the Shadowmen'' is an American anthology of short fiction edited by Jean-Marc Lofficier and Randy Lofficier and published by Black Coat Press. The stories share the conceit of taking place in a fictional world where all of the character ...

'', Doctor Omega and

investigate apergy. Apergy is also mentioned in the

Warren Ellis Warren Girard Ellis (born 16 February 1968) is a British comic book writer, novelist, and screenwriter. He is best known as the co-creator of several original comics series, including ''Transmetropolitan'' (1997–2002), ''Global Frequency'' ( ...

comic ''

Aetheric Mechanics ''Aetheric Mechanics'' is a graphic novella created by Eagle Award-winning writer Warren Ellis. It is 48 pages long, illustrated in black and white by Gianluca Pagliarani, (although the indicia include a September 2008 publication date the ...

'', as being generated by

Cavorite ''The First Men in the Moon'' is a scientific romance by the English author H. G. Wells, originally serialised in ''The Strand Magazine'' from December 1900 to August 1901 and published in hardcover in 1901, who called it one of his "fantasti ...

technology from ''

''.

Other terms

H. G. Wells Herbert George Wells"Wells, H. G."
Revised 18 May 2015. ''

'' has space travel based on the gravity-blocking properties of "

Philip Francis Nowlan Philip Francis Nowlan (; November 13, 1888 – February 1, 1940) was an American science fiction writer, best known as the creator of Buck Rogers. Biography Nowlan was born on November 13, 1888. While attending the University of Pennsylvania, N ...

's 1928 story ''

Armageddon 2419 A.D. ''Armageddon 2419 A.D.'' is a science fiction novella by Philip Francis Nowlan that first appeared in the August 1928 issue of the pulp magazine ''Amazing Stories''. A sequel called '' The Airlords of Han'' was published in the March 1929 iss ...

'' describes "inertron," a substance that falls up. The story was the basis for the

Buck Rogers Buck Rogers is a science fiction adventure hero and feature comic strip created by Philip Francis Nowlan first appearing in daily US newspapers on January 7, 1929, and subsequently appearing in Sunday newspapers, international newspapers, books ...

comic strip and adaptations.

References

Bibliography

Criteria:
"Newtons discovery of the apple law""Newtons principle of gravitation"

"Newtons principle of gravitation apple falls"
(google > google books)

External links

Responding to Mechanical Antigravity
a NASA paper debunking a wide variety of gyroscopic (and related) devices

{{DEFAULTSORT:Anti-Gravity General relativity History of physics History of science and technology in the United States Historiography of science Science fiction themes Fringe physics