Talk:Anti-gravity

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Removed "Lagrangian Points"[edit]

I have removed the following paragraph from the section "Conventional effects that mimic anti-gravity effects":

  • Multiple nearby gravity sources generate separate gravity fields. Thus, if an object is placed at a certain location between two sources (the so-called Lagrangian point, see picture), their gravity cancel out each other's. In this state, the object still experiences gravity, but from opposite directions with the same strength, so the resulting force is null.

It is not the gravity of the objects that cancels each other out, it is gravity *plus centrifugal forces*. The situation is very similar to a satellite staying in its orbit despite gravitation. --Lotharster --91.67.24.156 (talk) 13:11, 3 October 2008 (UTC)

Accelerating Objects Using Gravity[edit]

This is a general question to all Wikipedians: Using anti-gravity or some force of reversed gravity, would it be possible to accelerate a projectile to super speeds? I'm not talking about magnetic propulsion or anything of that sort, or a Gauss gun, but really taking an object, putting it in a chamber of some sort with Anti-Gravity or some sort of Zero-Gee space to make it reach higher speeds before going out and reacting to the Earth's gravity. You know, to make it faster. —Preceding unsigned comment added by 74.171.126.143 (talk) 03:29, 15 December 2008 (UTC)

Re: Tajmar effect tested in New Zealand[edit]

There is something amiss in what I have seen concerning this so-called testing of Tajmar's effect by the New Zealand group. For one thing, the discrepancy between the mass of Cooper pairs first measured in superconductors by Janet Tate et.al is a long-standing discrepancy. In New Scientist, 2006-11-11, Tate is quoted as saying The measurement has remained unexplained for the last 20 years. Whatever you may say about Tajmar's work, that discrepancy is still there and still remains unexplained. Moreover, at last check, the reported anomalies of the Gravity Probe B mission are also still unexplained. Thus, we still cannot rule out a gravito-magnetic effect.

Has anyone bothered to contact Tajmar directly? Because I did and this is what he tells me:

It's always the same problem that people just read abstracts only. The New Zealand group (Graham et al) tested my 2006 theory (which I already dismissed with my own experimental results) - not my experiment. They did not find any result with error bars two orders of magnitude above my signal strengths! If you read their paper they say in the last paragraph that their results can not confirm or refute my experimental claims but that they put limits on my old theoretical model.

So according to Tajmar, the New Zealand result is almost irrelevant. He also pointed me in the direction of a more recent paper (2008):

http://arxiv.org/abs/0806.2271v2

FYI, I would like to remind everyone: The astronomer William Wallace Campbell whose 1922 measurements of his observations of the Sun during a total eclipse in Australia would eventually confirm Einstein's predictions. However, before the said measurements, Campbell had made a preliminary set of measurements with inferior equipment during a solar eclipse of 1918 that did not confirm the results. He appeared at Cambridge and was about to refute Einstein's theory but Eddington had data, admittedly limited data, obtained from measurements precariously obtained during a solar eclipse in Africa that seem to confirm Einsein's bending of light.

Campbell decide to delay publication that would have refuted GRT, rather stating that yes, the Einstein theory is unsettled. In other words, Einstein's theory came very very close from being refuted before anybody invested in trying to vindicate it.

Imagine what would have happened had Campbell not been so conscientious?

Thus, I submit this section about the New Zealand group should be revised because it apparently does not really refute Tajmar's experimental findings and Tajmar has since discarded his theory. I would say the experimental result is unsettled NOT repudiated. I agree that Tajmar's experimental findings need to be vindicated and/or refuted by other groups, especially in America but this part of the web-site conveys the wrong and negative impression. Now. I could decide to be bold and make the changes myself but I would prefer not to enter a tug-of-war with the author(s) of this part of the web-site. I would like to get some feedback first But I submit that this part of the web-site conveys a premature conclusion and thus the wrong impression. —Preceding unsigned comment added by 171.71.55.135 (talk) 23:48, 18 December 2008 (UTC)

We can't really use the material directly from him, as it is unpublished.- (User) Wolfkeeper (Talk) 14:33, 25 March 2009 (UTC)

Anti-matter/gravity Question[edit]

The article states; "A longstanding question was whether or not these same equations applied to antimatter. The issue was considered solved in 1957 with the development of CPT symmetry, 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." Has this been tested/verified experimentally? (David Kessler) 19:32, 12 March 2009 (UTC) —Preceding unsigned comment added by 94.169.180.52 (talk)

No it has not conclusively been verified experimentally. It is in general impossible to currently verify it. Because antimatter is created in such small quantities compared to ordinary matter gravity whether acting positively or negatively on these atoms would have little effect on them compared to the electromagnetic forces acting on them. There is not any appreciable amounts of antimatter being produced in the foreseeable future to really test gravities effects on them in a way that eliminates the much more powerful force of electromagnetism acting on them. It currently costs about $100 trillion dollars to make one gram of antimatter. The Sun with all its power is only capable of making a few pounds of antimatter per year. So there is very little in the way of experiments to confidently describe all aspects of antimatter. A lot of current knowledge is theoretical or based on logic which doesn't always pan out. In fact there is far more unknown about antimatter then what is known. — Preceding unsigned comment added by 2601:B:A3C0:7:1130:3602:4402:4654 (talk) 06:15, 8 November 2013 (UTC)

there is no gravity . So the problem is not what antigravity is, but rather , what gravity is not. Gravity is not a force of attraction Gravity is a pressure force created by the 98% of the matter we know exists in the universe but that matter we don't know the nature of. I will speak more of this later.81.34.202.107 (talk) 20:07, 15 April 2009 (UTC)

I have been asking this same question about anti-particles (for different reasons) but so far have no answer. BTW if general relativity is correct gravity is a positive force created by positive curvature in space time, if quantum gravity is correct then its a force created by exchange of pairs of massless FTL information carrying particles called bosons (virtual particles  :) ). In special relativity terms gravity is an accelerating frame (gravity of course violates SR). Lucien86 (talk) 12:06, 15 July 2010 (UTC)

Gravity is not an attraction force[edit]

there is no gravity . So the problem is not what antigravity is, but rather , what gravity is not. Gravity is not a force of attraction Gravity is a pressure force created by the 98% of the matter we know exists in the universe but that matter we don't know the nature of. I will speak more of this later.81.34.202.107 (talk) 20:14, 15 April 2009 (UTC)

Request to modify or delete line[edit]

"There are numerous newer theories that add onto general relativity or replace it outright, and some of these appear to allow anti-gravity-like solutions. However, according to the current widely accepted physical theories, verified in experiments, and according to the major directions of physical research, it is considered highly unlikely that anti-gravity is possible" There is credible research on antigravity. The work of Dr. Ning Lee http://www.amasci.com/weird/vortex/tnews.txt has shown in labs to produce force fields that suspend objects and act as an antigravity effect. —Preceding unsigned comment added by 74.62.112.92 (talk) 20:26, 18 October 2009 (UTC)

anti-gravity as the polar force of gravity[edit]

The article does not seem to consider anti-gravity as the opposite polar force of gravity, which ironically seems also to be the force that is called dark energy.

In this context then dark matter would be the substance from which dark energy emanates and in that contect be anti-matter.

In a perfect world there would be a balance in the amount of matter and anti-matter and gravity and anti-gravity with an imbalance representing some type of transition in the universe.

Where is this concept discussed in the Wikipedia? 71.100.11.118 (talk) 03:08, 8 March 2010 (UTC)

an object in space[edit]

is there a normal force when an object is rested on a tables in space,and pushed by force F at an an angle thetha.

Wet Blanket[edit]

The writing here is terribly conservative. I doubt that a real scientist actually wrote this article. Gingermint (talk) 03:49, 14 June 2010 (UTC)

99.102.177.253 (talk) 23:23, 15 July 2010 (UTC) Electric Universe W Thornhill What is gravity?

Gravity is due to radially oriented electrostatic dipoles inside the Earth’s protons, neutrons and electrons.[18] The force between any two aligned electrostatic dipoles varies inversely as the fourth power of the distance between them and the combined force of similarly aligned electrostatic dipoles over a given surface is squared. The result is that the dipole-dipole force, which varies inversely as the fourth power between co-linear dipoles, becomes the familiar inverse square force of gravity for extended bodies. The gravitational and inertial response of matter can be seen to be due to an identical cause. The puzzling extreme weakness of gravity (one thousand trillion trillion trillion trillion times less than the electrostatic force) is a measure of the minute distortion of subatomic particles in a gravitational field.

"Anti-gravity " and momentum conservation[edit]

This query regarding the possibility of anti-gravity drives of the first kind has been moved to "Anti-gravity drives" and momentum conservation"; because the following article/ comment seems to be unrelated to it Rhnmcl (talk) 12:38, 18 October 2011 (UTC)



I removed the following text because it is an incorrect refutaion for the reason that a gravity shield will not work. "One might consider the results of placing such a substance under one-half of a wheel on a shaft. The side of the wheel above the substance would have no weight, while the other side would. This would cause the wheel to continually spin. The side NOT above the plate would "fall" while the side above the plate would experience little or no gravity from Earth and thus have no weight to counter balance the "falling" side. This motion could be harnessed to produce power for free, a clear violation of the first law of thermodynamics. More generally, it follows from Gauss's law that static inverse-square fields (such as Earth's gravitational field) cannot be blocked (magnetism is static, but is inverse-cube). Under general relativity, the entire concept is something of a non-sequitur."

The reason that this argument is fallacious is fairly simple to discuss. Bascilly, there is another inverse square force, the electrostic force, that can be used to test the hypothesis. So what one would do it charge a conductive plate, such as a piece of printed circuit board stock up to a known potential, as by using a battery or power supply. Then a shielding plate could be placed over a portion of the lower plate (with an appropriate equal and opposite potential applied), and a wheel made of a suitable dieletric substance could be charged up with a suitable test charge applied thereto. In this case, the charged wheel will with an absoute certainy NOT begin spontaneously spinning with the creation of more and more momentum. Now as for the reasons why, it is either because that would violate conservation of angular momentum, on the one hand - but obviously begging the question to simply state that - but on the other hand, one can if one is so inclined work out the problem of actually solving the problem of Laplace's equation in the vicinity of such an arrangement of charged plates, and then from that point, calculate the forces on an ensemble of test charges, with the reasonable expection that is the problem is treated numerically that the net force will be zero, or close there to taking into account the granularity of the mesh and round off errors. Anyone with a source for this should certainly feel free to move my analysis into the main article, with appropriate edits. As for myself, I have a physics degree from U.C. Berekeley, but there is still the issue of what constitutes "original research", even if it is an "obvious" application of the appropriate calculus. 67.116.237.103 (talk) 23:48, 29 July 2011 (UTC)

Woodward Effect[edit]

Given the wide range of topics on this page, a brief discussion of the Woodward Effect seems appropriate. —Preceding unsigned comment added by 69.132.111.97 (talk) 22:19, 19 December 2010 (UTC)

Possibilities in string theory.[edit]

String theory (and all other theories involving hidden dimensions) predict that gravity and electromagnetism unify in hidden dimensions and that the hidden dimensions are indetectible because of their small size. It does also predict that sufficiently short-waved photons, with wavelengths shorter than the size of the hidden dimensions, can enter them. Producing ultra-short photons can thus manipulate gravity, with revolutionizing space travel applications such as cheap anti-gravity launches. The problem that it would require high energy can be practically solved by concentrating several laser beams on a nanoparticle, heating it to locally extreme temperatures. An Alcubierre metric can be created by ejecting multiple nanoparticles from the craft and then beam perfectly timed laser beams on them (fire at the most distant first so that they are hit simultaneously), so each nanoparticle contributes a slower than light effect but together add up to faster than light, creating no discrete event horizon and thus no Hawking radiation.

By Martin J Sallberg — Preceding unsigned comment added by 94.191.166.80 (talk) 12:54, 4 August 2011 (UTC)

Anti-gravity in fiction[edit]

In the first paragraph it states that "Anti-gravity is a recurring concept in science fiction", but then it only mentions H. G. Wells's The First Men in the Moon. Later on, under "See also", there is a reference to "The spindizzy drive in the science fiction novels of James Blish". But two examples don't support the statement that it is a recurring concept. Are there any other verifiable examples? 95.149.106.250 (talk) 19:24, 12 September 2011 (UTC)

Anti-gravity is ridiculously common in science fiction. It's usually closely related to artificial gravity, force fields, and/or gravitic weapons. If you want specific references… well, the problem is that there are just too many. You'd have hundreds just from Star Trek, Star Wars, and Doctor Who alone. So what you'd need is a single reliable reference saying that it's common, not just more examples. But even that may be hard to find; it's so taken for granted that SF uses antigravity that you're more likely to find an article saying something like, "Of course the Fooites have antigrav, just like every other sci-fi race" than someone directly saying that antigrav is common. --70.36.140.225 (talk) 05:49, 6 October 2014 (UTC)

"Anti-gravity drives" and momentum conservation[edit]

Regarding the issue of the possibility of an anti-gravity drive.

Firstly 'what do we mean by an "anti-gravity" drive ?. As I understand General Relativity, the apparent gravitational force on a mass, is the result of a change in the 'curvature' of space-time; relative to the curvature of space-time in empty space. Contentions: 1/ a mass only 'knows' about that section of the space-time within the mass's volume . 2/ the apparent force needs to act identically at each point within the volume of the mass.Which is why a mass is subject to no differential stresses, whilst being accelerated in a uniform gravitational field.

So what I mean by an 'anti-gravity' drive in essence; is a change in the curvature of space-time,within the volume of a mass, which emulates that which would be caused by a suitable attractive mass.

Two possibilities exist for 'anti-gravity' drives as described above : 1/ with momentum conservation 2/ without momentum conservation I am not going to discuss the second possibility, firstly because it seems the more bizarre and secondly because it has for some reason already received much attention.

So the question of the possibility of an 'anti-gravity drive with momentum conservation'; seems to amount to the possibility of a hypothetical warping of space-time within the volume of a mass; whilst within the gravitational field of a second mass. The second mass being required ,in order to provide a means of conserving momentum. In particular since it is desirable that the curvature of space-time is uniform, within the volume of the first mass;in order to produce identical acceleration at each point and thus avoid differential stresses within the first mass.

The real question then seems to be: Is the intense curvature, which will be required in the volume just outside the volume of the first mass, where space time returns to the 'natural' curvature of space-time produced by the two masses : 1/possible; that is does it contradict General Relativity or Quantum-mechanics ? 2/if possible; can one work backwards from it's hypothetical existence;to infer anything useful regarding material conditions, which might generate it;in the way macroscopic worm-holes were explored ? Rhnmcl (talk) 12:28, 18 October 2011 (UTC)


[edited] I hate to point this out but an 'anti-gravity' engine that conserves momentum already exists and is called a rocket. Ultimately the argument about conservation seems a pretty irrelevant one because it depends on open verses closed systems. - If an object accelerates it may appear to violate conservation of momentum locally but ultimately the object (any object) is in an open system with the whole universe and momentum will be conserved. Rockets themselves are the perfect example of this - if you ignore the exhaust then a rocket produces an unbalanced thrust, but if you don't ignore the exhaust then rockets are actually completely incapable of acceleration!
For a gravity engine the reaction mass can ultimately be seen as either space time or some putative zero point, and instead of ejecting a hot flame exhaust the machine is trying to push against something infinitely more slippery. The real problem is that despite what many physicists say ordinary science really does not understand space time or the FTL-STL interface at all well. (just look at the gravity of black holes) From the standard theory FTL objects appear to violate the conservation of momentum but this is probably only because General Relativity is still an incomplete answer. FTL and Gravity manipulation are intimately connected. - A basic configuration that allows FTL motion is to have a net zero mass in a balance of negative and positive - this zero mass leaves momentum conserved but violates its principle. (this is a nightmarishly complex subject and the real answer today is a blank piece of map with a picture of a dragon drawn on it :) ) Lucien86 (talk) 22:55, 7 November 2011 (UTC)

Spelling[edit]

How should the word be spelled, "antigravity" or "anti-gravity"? The former looks more right to me and MW spells it as such, but are there reasons why this article uses the latter? Λυδαcιτγ 06:13, 5 December 2012 (UTC)

Scalar-Tensor Theory[edit]

There is no mention of scalar-tensor theory. E.g. the Brans-Dicke theory has a fudge factor to ensure agreement with Astronomical observations. I remember reading that scalar-tensor theories did not always produce solutions with a Newtonian limit. This is why they had imposed a canonical form of the scalar field as  \Phi = \phi^2 to ensure a positive field so that "anti-gravity" could not happen. But this prescription resulted from 'believing' that anti-gravity could not happen. Nonetheless, theoretically, some scalar-tensor theories could produce departures from Newtonian gravity. My point is that theoretically, "anti-gravity' is not yet ruled out.TonyMath (talk) 14:57, 28 April 2015 (UTC)

If there are a series of reliable sources on this it can be added. Fountains of Bryn Mawr (talk) 15:05, 28 April 2015 (UTC)
Ok let's start with this one Antigravity in F(R) and Brans-Dicke theories and its possibility in curvature quintessence]. This other one Quintessence scalar-tensor theories and non-Newtonian gravity talks about the possibility of non-Newtonian gravity. Let's start with that. These 3 references show that scalar-tensor theories admit the 'theoretical' possibility of departures from the Newtonian limit of gravity and hence what some would called anti-gravity. TonyMath (talk) 12:07, 1 May 2015 (UTC)
Some problems (and please take this as hopefully constructive nitpicking). Sourcing something is not the same as reliably sourcing it. Papers on a topic are not considered reliable sources because they are primary sources (see WP:PST) so "hence what some would called anti-gravity" comes off as WP:OR, its an interpretation of the papers. The article Scalar-tensor theory does not mention anti-gravity. It would be nice if there was something on the level of a Nature article about how "someone is calling this anti-gravity" - Wikipedia should be sourced to already well published ideas that appear in general publications, its not really an outlet for bleeding edge theory or interpretations there of. This also seems to be an article about hocum, not advanced cosmology. All that being said, if you can find a way to word it in following Wikipedia guidelines (like maybe a section on real theoretical anti-gravity) it could be a good addition. Fountains of Bryn Mawr (talk) 15:12, 1 May 2015 (UTC)
I think that perhaps more direct, or additional if not more prestigious references might help here. Consider dilatonic quantum gravity, ref 21, i.e. the paper by Mann and Ohta provides a solution with a non-Newtonian limit apart from a solution with a Newtonian limit. This is Jackiw–Teitelboim gravity theory, a scalar-tensor theory in $1+1$ dimensions. This paper is fundamental i.e. exact solutions of a self-interacting quantum gravitational system. It combines gravity theory, EM theory and quantum mechanics albeit in lower dimensions. This is not cosmology but could have applications in cosmology. It is part a first rate body of work by R.B. Mann and co-workers with publications in Classical and Quantum Gravity and Phys. Rev. D. However, I have the feeling that you want something more along the lines of Scientific American or Nature. Nonetheless, a 'en passant' statement that anti-gravity i.e. solutions with a Non-Newtonian limit are considered in scalar-tensor (quantum) gravity theories could be made. But you are probably right, that more along these lines needs to be worked out before any statement could be made in wikipedia.TonyMath (talk) 06:56, 2 May 2015 (UTC)

Does Crysis 1 feature Anti-gravity?[edit]

In the first game (Crysis) there are missions with zero gravity within alien spaceships (see: https://www.youtube.com/watch?v=6e2HjmL6B8s) and if I remember it correctly there were even frozen place outside which had a lessened force of gravity. Should it be added to the Video games section (anti-gravity seems to be implied there)? --Fixuture (talk) 18:20, 16 May 2015 (UTC)