Some time ago, I imagined a world with one peculiar disease. People affected by it suddenly "fall" towards the sky, never to be seen again. What could be the scientific cause of such a disease?

Some of its characteristics are:

  • it can affect living beings as well as objects and the environment itself: for example, dirt chunks, water, etc.
  • it doesn’t seem to spread through contact: a few bricks of a chimney can fall upwards, without the rest being affected
  • people affected by the disease can still live on the planet, but they’ll live upside down
  • it is permanent

Can there be a scientific explanation for this disease, even a pseudoscientific one, or does this fall in the “it’s magic” category? Feel free to tweak some of the characteristics if needed.

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    $\begingroup$ It's magic. Or an advanced alien prank. I'd go for the prank. $\endgroup$ – Keelhaul May 24 '17 at 12:16
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    $\begingroup$ Gravity inverting disease... Generally biology can't warp physics to its will. So to make this happen magic has to be involved no matter what. $\endgroup$ – Hyfnae May 24 '17 at 12:16
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    $\begingroup$ If it affects inanimate objects, it's NOT a disease $\endgroup$ – nzaman May 24 '17 at 12:49
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    $\begingroup$ Hydrogen balloonism. The swelling is super painful. Smokers tend to not survive it for long. You get it by drinking too much electrolyte-supplemented water...after a voodoo curse. $\endgroup$ – user535733 May 24 '17 at 13:07
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    $\begingroup$ @sphennings - You use a lot of big words whilst wiggling your fingers. $\endgroup$ – amflare May 24 '17 at 16:31

25 Answers 25


It makes perfect sense if your aliens are benthic marine creatures.

Falling upwards into the sky doesn't make sense if your aliens are humanoids living on solid ground beneath an Earth-like atmosphere. However, if your aliens are, instead, benthic life forms living at the bottom of an ocean, a disease causing them to fall upwards would make a lot more sense.

The disease would be caused by gas producing microbes. If they produced gasses at a faster rate than the organism could expel them, they'd become buoyant and float away. Creatures afflicted by "the floats" would need to wear weights whenever they wanted to go outside, in order to remain anchored to the seabed. Floating away would be fatal if the gasses were unable to escape from their host. As the afflicted creatures rose through the water column, the internal pockets of trapped gas would expand, rupturing their internal organs.

Inanimate objects could also succumb to the floats, provided they're suitable places for bacteria to colonize. Bricks would likely be immune, but objects made of wood or other organic materials could fill with internal gasses and float away.

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    $\begingroup$ It does not absolutely have to be marine. It could be in a dense gaseous atmosphere, with the disease turning organisms into living gasbags $\endgroup$ – Evpok May 24 '17 at 16:53
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    $\begingroup$ I initially thought in humans that a hydrogen-producing bacterium might cause this, but hydrogen only lifts 68 lbs per 1000 cu ft., so it would be fatal long before there was any lift. Frankly, as much as I like this idea, I suspect that this would also be the case in a marine or dense gaseous atmosphere as well. $\endgroup$ – Doug R. May 24 '17 at 20:59
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    $\begingroup$ I thought about denser atmospheres, but I don't think there's any good candidate gasses for an atmosphere to be composed of in which gas accumulation could reasonably cause an organism to float. Even something like SF6 only has a density of 6 kg/m^3, so the volume of a lighter gas required to lift something like a person (density around 1000 kg/m^3 for water) would greatly exceed the volume of the person being lifted. Marine organisms, in contrast, are often already close to buoyancy neutral. $\endgroup$ – ckersch May 24 '17 at 21:56
  • $\begingroup$ @ckersch see some older posts about life in a supercritical fluid as another alternative. $\endgroup$ – JDługosz May 25 '17 at 5:48
  • $\begingroup$ In a denser, stormy atmosphere, you could have creatures that float and fly normally on the outer edge of a gas giant where life has trouble surviving closer to the core. The disease could have a similar effect, causing the creatures to lose control of their buoyancy. $\endgroup$ – Samthere May 25 '17 at 9:41

Our current understanding of physics does not have a mechanism for the sudden reversal of gravity. Any science based explanation of this effect requires a science sufficiently advanced to be indistinguishable from magic.

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    $\begingroup$ As much as I think this is the correct answer, I do want to point out that it made it into the VLQ queue. $\endgroup$ – user May 26 '17 at 21:05
  • $\begingroup$ @MichaelKjörling Why was it VLQ. Any suggestions on how to improve the answer's quality? $\endgroup$ – sphennings May 28 '17 at 0:20
  • $\begingroup$ Sorry, I don't know; all I saw was the generic "because of its length or content" reason. $\endgroup$ – user May 28 '17 at 9:41
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    $\begingroup$ @MichaelKjörling: I don't see a way out of it. You'd just about have to build physics around making this work. $\endgroup$ – Joshua May 28 '17 at 14:25
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    $\begingroup$ @Joshua ...and by the time you do, then it's no longer science-based. Magic of all kinds is fine, and it has its place; as does lampshading. You just have to work harder as an author or story-teller to maintain your audience's suspension of disbelief. $\endgroup$ – user May 28 '17 at 14:30

With sufficient worldbuilding, your creatures could be affected by

Electric Imbalance Syndrome (EIS)

Similar to amflare's answer, but differing in that Electric Imbalance Syndrome is biological in nature instead of affecting whatever happens to be unlucky enough to be nearby when the sun decides to screw everyone over.

Gravity is indeed a much weaker force than electric force. How much weaker?

Newtonian gravity is modeled by the equation $F_g = G\frac{Mm}{r^2}$. Electric force is modeled similarly by $F_e = \frac{1}{4\pi\epsilon_0}\frac{q_1q_2}{r^2}$.

We can compare them, quite simply, by dividing one by the other:

$$\frac{F_e}{F_g} = \frac{1}{4\pi\epsilon_0}\frac{q_1q_2}{r^2}\frac{r^2}{GMm} = \frac{q_1q_2}{4\pi\epsilon_0GMm}$$

Substituting in all the constants and canceling $r^2$, this comes to

$$\frac{F_e}{F_g} = \left(1.35 \times 10^{20} \frac{kg^2}{C^2}\right)\frac{q_1q_2}{Mm}$$

If we choose two protons to use as our basis for comparison, the charge of a proton is $1.60 \times 10^{-19} C$ and the mass of a proton is $1.67 \times 10^{-27} kg$, so plug all that in and we find that the electric force between them is

$$\frac{F_e}{F_g} = \left(1.35 \times 10^{20} \frac{kg^2}{C^2}\right)\frac{(1.60 \times 10^{-19} C)^2}{(1.67 \times 10^{-27} kg)^2} = 1.24 \times 10^{36}$$

So the electric force between them is roughly $10^{36}$ times stronger than the gravitational force, if I did my math right.

So perhaps your planet is composed largely of minerals with a low conductivity (insulators) and contains positive or negative charges distributed uniformly within. This will result in a near-uniform electric field directed toward or away from the planet. This way, any charges in the creatures' bodies will cause them to be attracted to or repelled from the planet. A very delicate balance of positive and negative electric charges is then necessary for your species to survive.

Perhaps these charges will be balanced through diet, like vitamins. Eat too much of foods with one charge and find yourself being pulled "heavily" toward the ground. Eat too much of the other and risk flying off into the sky. When perfectly balanced, the creatures experience only gravity, as we do on Earth. Perhaps optimal balance should keep the creature a little "light" on its feet to reduce wear on the legs, feet and knees.

Natural excretion will no doubt regulate these charges as the majority charge will be repelled and the minority charge attracted. Foods that reinforce the electric imbalance would also be difficult to pick up or eat. But perhaps sufficiently poor diet could outpace these natural processes or simply provide no charges to counteract the effect of the majority charge, or perhaps some illness causes' the creature's antibodies to forcefully expel either positive or negative charges.

EIS could theoretically function in either variety, the kind that pulls the victim to the ground or the kind that flings the victim into the air. These could be known as Positive EIS and Negative EIS, depending on the charge of the planet itself. Proper worldbuilding could make one much more rare than the other. Perhaps negatively-charged food is uncommon or unpleasant on this positively-charged planet. In such event, Positive EIS is the common condition where a creature's body tends away from the planet, eventually sending them off into the clouds.

There is little hope for someone whose fate lies in the sky, as both gravity and electric force scale with distance squared. Once a creature's outward-directed electric force exceeds its inward-directed gravitational force, it always will regardless of how far away the creature's body moves. Those who are fortunate enough to be indoors at such time may be saved, or perhaps someone surrounded by quick-acting friends might as well.

If these charges are to stay within the body, which they must if this entire world is to work, the creature's skin must also be an insulator. As such, one potential remedy is to simply break the skin at the top of the head and allow the outward-tending charges to escape on their own.

Another remedy might be pharmaceutical charge tablets that maintain one's charge when used as directed by your doctor. Do not use these tablets if you are nursing, pregnant or may become pregnant. Side effects include bleeding, shortness of breath, acute pain and difficulty excreting. Contact your doctor if you experience an... well, you know the rest.

  • $\begingroup$ A force $10^{36}$ times the gravitational force is immense. It would take some worldbuilding to conceive creatures that can live in such an environment. $\endgroup$ – Klangen May 26 '17 at 8:56
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    $\begingroup$ @Pickle It's a comparison I've always considered a little misleading. The creatures living in this world wouldn't experience a force $10^{36}$ times as great as gravity unless they were made entirely of protons (or entirely of electrons). $\endgroup$ – Devsman May 26 '17 at 12:25
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    $\begingroup$ What keeps sufferers from being struck by lightning before they get to the point of flying off? $\endgroup$ – Spencer May 27 '17 at 11:36
  • $\begingroup$ @Spencer Insulator skin. I suppose the same things that keep sufferers from being struck by lightning in our world would also help. Remember that the world itself is also charged, which would largely nullify the preference for striking said sufferers over a mountain peak or tall building. $\endgroup$ – Devsman May 30 '17 at 12:26
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    $\begingroup$ @Spencer I believe insulators prevent or resist the movement of their own electrons but allow fields. If I'm not mistaken, this is how a capacitor works. $\endgroup$ – Devsman May 30 '17 at 20:44

Kinda pseudo-sciency, but the OP has explicitly allowed it:

Negative mass wiki link

In theoretical physics, negative mass is matter whose mass is of opposite sign to the mass of normal matter, e.g. −2 kg. Such matter would violate one or more energy conditions and show some strange properties, stemming from the ambiguity as to whether attraction should refer to force or the oppositely oriented acceleration for negative mass.

So, what is it? Well, it's been theorised about, but obviously never been proven (to my knowlege) to actually be possible, yet alone existing anywhere.

An object with negative mass will actively 'push' away from any positively massed object (force of gravity). It also repells itself iirc, but gravity is a weak force, so objects would remain solid, but negative masses would not coalesce in space for example.

All you need now is some quantum level hijinks that change the mass of [some collection of atoms] though some internal means, some sort of virus perhaps? or some sort of weird radiation maybe.

somewhat odd could be that parts of objects could be affected too, maybe your arm gets affected first, and suddenly starts falling up, while the rest of your body is still attracted by gravity the normal way.
You would get some interesting effects too. Should it be localised, and your people become spacefaring, linking negative and positive masses together would provide an unlimited amount of small accelleration, so would be very useful for a space-faring race wishing to visit other galaxies (it would still take a very long time to get there, but it uses no fuel - point at destination, turn around halfway there)

As for why you would fall up, when gravity is weak, it may be, but the earth is big, hence we fall down.

Someone a little worse than 50% affected would end up like: relavent xkcd

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    $\begingroup$ This is close to what I had in mind -- perhaps something akin to radiation emits particles which penetrate an individual and disrupt the normal spin in their particles such that gravity is reversed and their mass is repelled by the Earth. As to whether this is an illness, it might also be that an infectious "organism" (not in the normal sense) metabolizes at the subatomic level rather than the chemical level, and its waste consists of particles somehow angled to the time axis and can knock other particles into this new orientation. The person still experiences time but falls upward. $\endgroup$ – Epanoui May 24 '17 at 17:22
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    $\begingroup$ If negative mass were repelled by gravity, 0-mass things would have to be unaffected by gravity. This has already been observed to not be the case. $\endgroup$ – JDługosz May 25 '17 at 5:42
  • $\begingroup$ @JDługosz evidence? If you are referring to gravitational lensing, then that is due to the curvature of space-time, not any forces acting on photons. $\endgroup$ – Baldrickk May 25 '17 at 7:17
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    $\begingroup$ @Baldrickk riiiiigh— this curvature is the explaination of the effects of gravity, and is the same reason planets stay in orbit. You just showed why all things, whether positive, negative, or zero mass, will be attracted to mass in the identical way. To make it clear, the curvature is a deeper model of why we feel a force. The curvature in the time dimension exactly reproduces Newton’s Laws of gravity. More subtle effects are due to the fact that space-time is not bending purely in the t direction. $\endgroup$ – JDługosz May 25 '17 at 18:08
  • $\begingroup$ Something of negative gravity would push other things away from it but be attracted to a thing of positive gravity. Unfortunately you'll need some new pseudo-science to deal with this. $\endgroup$ – wizzwizz4 May 26 '17 at 18:44

Here is my best guess: An intelligent species/civilization/entity that exists on very small scales (a couple of nanometers, maybe up to the size of a microbe, maybe subatomic (sci fi!)) that has developed a knowledge of gravity that allows make this happen. Is it possible? Nobody knows. But why not. Alternatively, you could have a species that just does this without knowing how and why or even being aware of it. All your symptoms can then be explained via "that's just how that lifeform works".

We do not really understand gravity. This leaves a lot of room for fiction.

I have seen things like my suggestion in a lot of science fiction media over the years that made good money without anybody complaining. While your flying dirt might not make a lot of money, you would be in good company with a half-baked explanation via a species that just does things because it can.

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    $\begingroup$ Small scale could make this crazy premise work. Static charges on small things can be powerful enough to overcome gravity. If these "people" are of a scale where static charge (or if smaller, other forces) are relevant that could be the answer. $\endgroup$ – Willk May 24 '17 at 14:43
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    $\begingroup$ I really like that idea of small, VERY small people. i can imagine a full novel with that disease where the whole time the reader is convinced this is pseudo-science... Only to realize at the punchline that it is in fact fully scientific, the reader was just in the wrong scale... $\endgroup$ – Patrice May 24 '17 at 21:51

Gravity is an extremely weak force. In fact, you need literally astronomicals amount of mass to generate any at all. Magnetism, however, is much stronger. Both attracting and repelling.

The magnetic field of the earth is about 99% contained in the core and the last 1% is the part that is outside the earth's crust.

So here is my premise. Some solar radiation makes it through the magnetic field and affects the atomic structure of things all the time. But sometimes, enough of it makes it through to cause not only a couple of atoms to get altered, but many of them, at once. These atoms have their magnetic properties flipped, so instead of disintegrating, they hold together, just with the opposite magnetic state. If enough of these flip, the person (or object) suddenly has a massive magnet under their feet repelling them away. Since magnetic forces are so much stronger than gravitational forces, this causes the person/object to "fall" into the sky.

You want a disease, you could say something like a weakened immune system means you have less energy which means your cells (and their component atoms) are less protected from the solar bombardments. So it could be a genetic thing, or really any wasting disease.

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    $\begingroup$ Interesting! Or the disease could be induced by a weapon that somehow engineers the change in polarity in the victim's body. $\endgroup$ – underscore_d May 27 '17 at 18:22

How does gravity work?

The feasibility of this behavior depends on the nature of gravity in your universe.

In our world, gravity was arguably first accurately described (but not explained) by classical Newtonian mechanics. In this interpretation, gravity is a mysterious force that acts upon all objects at a distance. But what's generating this force? Where does it come from?

Consider this quote from Newton himself:

That gravity should be innate, inherent, and essential to matter, so that one body may act upon another at a distance through a vacuum without the mediation of anything else, by and through which their action and force may be conveyed from one to another, is to me so great an absurdity that I believe no man who has in philosophical matters a competent faculty of thinking can ever fall into it.

(In the real world, this was eventually reconciled through Einstein's theory of General Relativity, which posits that all objects are constantly in freefall, and that mass merely warps the structure of spacetime, affecting the direction and rate of that freefall.)

Mechanical explanations of gravitation

The problem of how gravitational effects are generated seemingly from nowhere caused a great deal of scientific exploration down avenues that we now consider dead ends, but which at the time were serious attempts to explain gravity through solid mathematics and universally recognized mechanical processes and laws of motion.

These obsolete theories can be referred to as Mechanical or Kinetic theories of gravitation. Here are a few examples:

  • Screening: The universe is flooded with tiny particles or waves traveling at high speed in all directions (let's call them gravitons). An object alone in space is bombarded by these gravitons on all sides with equal force, for no net effect. But when you introduce another nearby massive object, that object screens some of these gravitons, preventing them from reaching the first object and thus upsetting the balance, so it starts to move in the direction of the screening object.

  • Vortex: The universe is naturally jam-packed with aether which is in constant motion. It moves in circles around massive bodies. Centrifigul force pushes fine matter to the outer edges of these aether vortices while heavy matter resists (with its greater inertia) and eventually finds itself pushed toward the center due to the pressure imbalance. The visible effect of gravity is comparable to stirring a cup of hot chocolate and watching the foam congregate in the center of the vortex thus produced.

  • Streams: The universe is (again) naturally jam-packed with aether, but matter acts like a sponge, soaking up the aether, and then either absorbing it (converting it into mass or energy) or transferring it into another world or dimension.

  • Waves and Pulsation: All bodies pulsate, sending waves through the aether. Depending on the theory, either the wavelength or the phase of pulsation determines whether two bodies will attract or repel each other. This stems from the observation that if two spheres suspended in a fluid pulsate in phase, they will attract each other, but if they pulsate out of phase, they will repel each other.

Reversing gravity

If in your world you adopt one of these mechanical explanations for gravity, then you might be able to find ways in which to explain the reversal of the effects of gravity.

In particular, if gravity is caused by all matter naturally and invisibly pulsating in phase, putting an object's natural pulsation out of phase will result in it being repelled by ordinary matter (and possibly attracted to matter pulsating at the same phase as itself).

Or if gravity is caused by streams of aether being absorbed into matter and sent into another dimension via some invisible gateway, a reversal of that flow such that streams of aether burst out of a body of matter might produce a localized repulsive effect.


Virtual Reality

The simulation hypothesis is the idea that we are currently living in a simulation, virtual reality so real it's indistinguishable from reality (though if we've always lived here we wouldn't know what "real" reality was). Your disease could be a computer virus (or glitch) that simply flips simulated gravity for someone. This could even manifest itself with outward "biological" indicators (besides suddenly falling upwards).

The simulation could be central to your plot, or one of those things that people piece together and you only ever coyly acknowledge it.


As far as we know today, it's magic

However, if you just wanted something "science'y" enough to sound feasible, you could describe it as less of a disease, and more of a "lethal dose of 'G' particles". You could say that when a traditional sub-atomic particle comes into contact with this G-particle, the normal particle gains a negative reaction to gravimetric forces and the G-particle is consumed. As a result, if some area is bombarded with trillions of these particles, enough of them could cause traditional matter to simply float away, including air, earth, fauna, and unsuspecting folk. Also this method would allow for varying degrees of the condition, i.e. Tim is currently at 20% normal G so he's able to essentially moon walk, where as Sally was exposed much more and needs to be bolted down at her −2% G.

The source of these particles could be some unknown interstellar event that happened trillions of light-years away, or even some localized event that was triggered behind the scenes by the Large Hadron Collider.

The realm of sub-atomic is one of the great frontiers of our time, with new theories popping up all the time. If you want to sneak in a magic particle, there's plenty of room for it right next to string theory (from your average reader's perspective).


Malfunctioning alien technology

Clearly, it can't be explained by known science. It isn't even a biologcal disease as it also affects minerals of various forms. You could explain it by magic (acient weird curse ?), but I prefer alien pseudo science, it is way cooler.

So, let's say some advanced alien civilization has based most of its industry on nanorobots. In order to move, these nanobots are embedded with some anti-gravity device. For some reason, a batch of nanobots are built with a defective component, making them behave weirdly. The aliens get rid of it by throwing it off in the cold deep void of space, and the defective nanobots end up... in your world.

Quickly, they start to act like some sort of virus, spreading without distinction (and without apparent logic) into both biological and mineral bodies. They don't cause much harm, maybe only harvesting a billionth of the host mass to duplicate themselves (they may have some hardcoded limits in order to avoid a true "grey goo" scenario), but remember : they are defective antigravity nanobots. As soon as they have duplicated, they activate their antigravity fields at full power for some illogical reason, and stay binded to their host forever.

As the symptoms you describe seem quite random, I think a defective antigravitic nanobot scums infection is the most probable cause of it.

(OK, I laughed at "most probable")

  • $\begingroup$ Perhaps they don't stay bound to their host forever - although those that have switched into "replicate" mode will remain, slowly (slowly!) converting their host into nanobots that will leave the host and infect. This could also explain increasing antigravity - not all of the created nanobots leave the host. $\endgroup$ – wizzwizz4 May 26 '17 at 18:56

Okay, this might be a stretch but so is the question.

For this to work in some pseudo scientific way, biology and physics have to be tied. I think your best bet is to stretch the interpretation of the observer effect in Physics.


You make the case that this disease affects the way the consciousness observes the universe. You also make the case that gravity is in some mysterious way tied to observation of the universe.

Again, this is a misrepresentation of the observer effect, but by using science concepts that readers don't fully understand, the reader may give you the benefit of the doubt, as well as opening up some interesting dialog or plot based around these concepts.


This may be more fiction than science, but...

Gravity Decay

Apparently, we didn't understand gravity as well as we thought we did. Scientists have recently learned about small pockets in the gravitational field which seem to be "decaying", or breaking down in some unknown way.

There are some folks who believe it's a sickness... They think people are falling ill (or in this case, "floating ill") because of some theoretical new virus. But if the scientists dig deep enough, they'll realize this isn't a medical condition at all.

This isn't a health problem, it's a physics problem.

  • $\begingroup$ That's actually a really neat idea - a planet with variable gravity decay $\endgroup$ – Klangen May 26 '17 at 8:58

I think you could turn the problem around. Generally, make it an active process to stay down, and the normal behavior is to fall away. Diseases can compromise processes; they don’t create new complex things.

In the linked Answer, life is under the shell covering Europa. “down” is supplied by boyancy, as the reef and complex ecosystem is hugging the underside of the ice. Life evolved early on a cellular level to be boyant or fall away. Benthic life will be definitely boyant on a full time basis; swimming forms will have some boyancy control organ. A disease can affect the latter easily enough. For crawling live, interfering with the cells metabolism to make them not-boyant could be a very mysterious illness, since there is no identifiable mass growing in the body causing it.

You can look over other answers to How would a “reversed planet” be able to exist? and turn each of them into “…and how does that go wrong?” for many more ideas.

In chat, we were discussing life on the outside of a body rotating so fast as to be greater than orbital speed. Loose objects are flung off. Anything living or working there must have some way of cancelling that; say, by generating a magnetic field. An illness that knocks out that ability will have the creature flung off the world.


Your question basically has two parts.

How would something fall up?

There are some theories that particles could exist which are affected inversely by gravity, such that rather than being pulled toward the source of gravity, they are repelled by it. We would not normally be able to find such particles, since 1- they would never be near any normal matter, and 2- the particles could never form a large object together on their own through gravity.

How would a disease cause this?

Since you have specified a disease, I assume that you intend for microbes or parasites to be the cause of the effect. So how about this: a microbe that, when it consumes matter, converts it into this type of theoretical anti-gravity matter. The matter would remain inside the human body, despite being pulled in the opposite direction by gravity. And if the chemical properties of the matter were unchanged by the anti-gravity conversion process, then the body's biological processes would treat it like any other matter. The matter would be combined in with normal matter in your blood and cells, where gravity's effect is overcome by strong atomic forces.

Given that the human body is already under normal gravitic pull and does not fall apart or suffer some sort of circulatory failure, it is fair to assume that having some of the matter in your body pulled in the opposite direction with identical force would not cause your body to fall apart or die immediately.

The greatest danger would be a "head rush" - humans who hang upside down for too long can have blood accumulate in their heads, causing loss of consciousness. But in our case, we only need 50.01% of the body's matter to be converted to anti-gravity matter in order for the person to experience weightlessness similar to zero-G that begins to cause them to rise into the air.

The biggest obstacle here is: how would microbes do this? Changing the physical properties of matter is no small feat, one would expect a facility like the LHC to be required to carry out this process. But much of Science Fiction is playing with "what if the rules were a little different?" scenarios, so if we assume that a microbe can do this, then it could produce the effect you're interested in.


On our current knowledge, nothing. "Disease" means always something at most on the atomic level. There is no known effect to change gravity on this level.

However, in the realm of the sci-fi/fantasy it is possible. Particularly the Star Trek had a lot of episodes about living beings using at least partially matter structures below (or differently) as the atomic level. You can search for things like "biomemetic gel", "neuroleptic virus", "nucleogenic lifeform" and similar things.

For example, the writers of the Star Trek have this last so imagined:

Nucleogenic lifeform

"Nucleogenic lifeform" is a latinic neologism, it tries to mean a lifeform whose biological processes are going not only on the atomic, but partially on the particle physical level. In the referred episodes, some rogue humans killed them and processed their bodies to spaceship fuel.

If anything useful - for example, a stable super-symmetric particle could be produced, in theory it wouldn't be impossible that these particles also take part in biophysical processes.

On the current scientific knowledge, there is nothing similar what we known doing this. But also nothing forbids it - only it seems very, very unrealistic.

String theory predicts a significant cooperation between supersymmetry and gravitons.

  • $\begingroup$ "it tries to mean a lifeform whose biological processes are going not only on the atomic, but partially on the particle physical level." I don't remember this in-show. Where was it mentioned, in an episode or in some external commentary? $\endgroup$ – underscore_d May 27 '17 at 18:24
  • $\begingroup$ @underscore_d In the Equinox episodes. Nucleogenic lifeform, it was the name of the aliens who were killed by the Equinox crew and processed their body to improve their speed to home. $\endgroup$ – Gray Sheep May 27 '17 at 21:45
  • $\begingroup$ Uh, yeah, I remember that. What I don't recall is any dialogue about why they were called "nucleogenic" and how that related to biological processes occurring at the particle-physics level. A quick glance at Memory Alpha seems to talk about them emitting antimatter, so I guess that's what you meant? I'm not a physicist. :P $\endgroup$ – underscore_d May 28 '17 at 9:46
  • $\begingroup$ @underscore_d Only antimatter is not enough for that, antigravity and faster than light things are yet another level deeper. It is unknown for the today's physics and it seems strongly that this current obstacle is far harder as the previous ones. But the authors of the Star Trek probably didn't know it, or it was for them not important. I think the biophysics of these aliens included, at least partially, reactions below the atomical level. This is were they named "nucleogenic". Remember, the core particles of the atom are the nucleons (proton, neutron and their antiparticles in antiatoms). $\endgroup$ – Gray Sheep May 28 '17 at 21:31
  • $\begingroup$ Right, so your intepretation of what nucleogenic means is an inference, not something that was stated in canon. That's all I was wondering about. Thanks! $\endgroup$ – underscore_d May 28 '17 at 21:32

I propose something similar to ckersch's answer, but I think you can pull it off on land. Not with human-like creatures, though.

Your creatures are only slightly heavier than air, and naturally have pockets of lighter-than-air gas in their bodies in order to be so.

(they're probably flyers whose lightness help them fly)

The disease disrupts the balance of these gas pockets, inflating them, until the person is literally lighter than air, and starts to fall upwards.

(if fliers, they can fly back down, but takes effort. One couldn't take a nap outside and fly back, way too much work. Optional: the disease progresses until you can't fly down fast enough for more than three minutes. Then one minute. Than not at all)


Living beings contain hydrogen, hydrogen gas is lighter than air, and there are some bacteria that produce hydrogen gas as a byproduct of their metabolism. So maybe some parasite turns things into hydrogen balloons?

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    $\begingroup$ I think a baloon large enough to lift someone would be noticed and lanced long efore it got to that point. $\endgroup$ – JDługosz May 24 '17 at 20:34

It's a pretty established trope that, shock horror, what we initially thought was a disease was actually nanobots all along.

But how could nanobots cause people to float? They could make them less dense than the surrounds, through the use of really light gasses. But as others have pointed out, that requires a very heavy atmosphere.

No, what we need is a force much stronger than gravity.

Luckily, we have 3.


Strong nuclear force.

Weak nuclear force.

The nuclear forces fall off significantly with distance, so electromag seems the best bet.

Maybe these nanobots are powered by a coil of wire made from a room temperature superconductor. This would set up magnetic fields in the nanobots that cause them to be attracted/repelled from magnets, depending on polarity.

Perhaps there is a mothership in orbit that is powered by a similar (but larger) coil of superconducting wire. This could be the aliens' way of recovering their nanobots after they have done their job.


Who are the people of this world?

They are spiritual, non-corporeal creative beings with the ability to manifest a physical reality in which they are able to do all manner of things using these forms. Unfortunately, the physical forms that call themselves humans have somehow disconnected from the spiritual forms, as well as from some of the other physical forms they created, and have mostly forgotten that they themselves are simply different forms of all that exists in the world they live in: their current "planet", its atmosphere, its less animate matter, its very animate matter, and all of its physical laws. One of the laws they created includes the concept of gravity, which they created as part of a complex concept that helps keep their different forms physically connected. They chose to orient this force to the largest form they became, the planet Earth, about which all their other forms enjoy their various activities and explorations.

What is the falling up disease?

Some of the humans go through a variety of spiritual awakening processes that trigger the ability to reconnect to their spiritual form, and most often also their other forms on the planet. For some, it includes the ability to rework the physical laws they create, and although usually unintentional, they begin to fall upwards, no longer bound by gravity. Before their spiritual transformation, these people had unknowingly reconnected to different "non-living" and living forms through their interactions with them, and these forms now also begin to reconnect with the spiritual self. The brick this person carved his initials in, combined with more initials, and surrounded with a heart shape when he fell in love with a girl, became far more connected to that form of himself than the rest of the house did. The piece of ground where a woman gave birth experienced her joy with her, and was able to reconnect to her. These forms "fall up" with the person. It is a physically manifested opposite of the idea humans speak of as "losing a piece of themselves". They partially regain these pieces.

This is a gradual process, and most of the reconnecting humans still don't understand the full concept of what they truly are as they experience it. They also interpret this process in different ways. Therefore, the majority of them can't explain it well to others, which causes uneasiness, or dis-ease. It's widely considered a disease due to poor understanding.

A few do begin to understand, but they enjoy using metaphor to share the message. It leaves some room for interpretation. After all, these beings didn't create this world they manifest in so they could become bored and inert. They thrive on the challenge, growth and learning.

  • $\begingroup$ The op didn't include other parts of the solar system and universe in the question, but it's easy to imagine how they could be other examples of the very same process, with their creative beings having chosen different physical forms and laws, and interacting with each other in coordinated ways. $\endgroup$ – N2ition May 25 '17 at 15:16

So something not caused by physical contact means the cause could be a form of radiation. This radiation could be a specific type of radiation that only affects the higgs-boson particle (dislocates & replaces it or destroys it). Since the higgs-boson gives matter mass destroying it would mean that the matter has less mass. The effect would be irreversible.

So your planet could be bathed in a constant but variable intensity stream of this radiation (sort of like UV radiation from our own sun) Over time people and objects would become exposed to this radiation, at some point they would exhibit symptoms become lighter and then suddenly float up. Just like UV exposure here the exposure levels would be wildly inconsistent from individual to individual.

  • $\begingroup$ The boson is an excited state of the field. The mass is not caused by particles but by interaction with the field. Making it cough up a boson was a trick to show us that the field existed and worked as expected; not something that is present in normal matter. $\endgroup$ – JDługosz May 25 '17 at 19:27
  • $\begingroup$ In any case, most of your mass does not come from the Higgs mechanism, as explained on the physics stack exchange. $\endgroup$ – JDługosz May 25 '17 at 19:29
  • $\begingroup$ So… rather tha “dislocates or exchange it”, make that “change the 'charge' as felt by the Higgs field”. But, as previously noted, that will not remove the bulk of your mass. $\endgroup$ – JDługosz May 25 '17 at 19:31

This might be a bit off the rails, as I don't have the math, but here is how I'd explain it:

Your planet is situated very near a black hole, relatively speaking. Maybe near the center of the galaxy. There are also several quasars in the vicinity. This stuff is very close, cosmically speaking.

The Black hole gives off an as yet unidentified kind of radiation or particle that is quantum in nature, as in it does not behave in the same way as you would expect with Newtonian physics.

Another as yet unidentified particle or radiation spins off of the quasars. Where they intersect, the energy from the quasar makes the particle from the black hole propagate throughout matter if it happens to be in the area by altering the nuclei of all the atoms in a certain area.

Those nuclei take on the properties that generate a strong negative or inverse of gravity. If the collision happens in something like a chimney of a house, it may only affect one or 2 bricks, but the rest will stay in place

If the collision happens in a person or animal, they fall up, accelerating away from the local dominant gravity well. If they are inside, they fall to the ceiling and live life upside down, making trips to the bathroom really awkward.

People and animals are the most affected because they are light enough to be launched skyward, while other things that have also had this happen are just weighed down and anchored to the ground. Plants have roots to keep them down. rocks are simply too massive. Animals are not anchored, and ones in the wild hit by this won't be noticed when they fly away. Sheep would float away from the flock and the shepherd would just get accused of being careless or drunk.

This way, you could have the effects be random, and have it seem like a disease, while also having it affect inanimate objects.

  • $\begingroup$ Because black holes = magic? Oh, quasars are not close. They are the most distant things that can be seen, in fact. $\endgroup$ – JDługosz May 25 '17 at 23:25
  • $\begingroup$ @JDługosz Black holes aren't magic, they are just stuffed with Handwavium! So far as the quasars, I meant relatively close to the black hole in question as well as the planet in question. Not close to us $\endgroup$ – Paul TIKI May 26 '17 at 13:09
  • $\begingroup$ A quasar is an active galactic center (powered by the black hole) that existed billions of years ago when the galaxies were forming. They are not near anyone now and are seen far away because of when tney existed. If one did fire up again, due to a galaxy merger say, the merging galaxies are a much larger scale than points of interest within a galaxy. You might describe that situation better, understanding that. Your second paragraph seems like you envision quasars to be star-sized. $\endgroup$ – JDługosz May 26 '17 at 20:29
  • $\begingroup$ @JDługosz Honestly, I have no idea. The only thing I remember about quasars is that they spin and emit...stuff, radio waves, whatever. I think the most in depth research I ever did on them was an episode of "Cosmos" when I was eight (the Carl Sagan one. Yes, I am old) Perhaps another astronomical phenomenon would be a better fit, but I don't know what else to use. Just that there needs to be Handvwavium A combines Handwavium B to create the effect $\endgroup$ – Paul TIKI May 26 '17 at 20:40
  • $\begingroup$ That makes you younger than me. You should find the wikipedia link interesting — a lot has been discovered since 1980. $\endgroup$ – JDługosz May 26 '17 at 20:54

Many ocean-dwelling creatures use swim bladders filled with gas to control their elevation. A disease that causes the swim bladder to be overfilled and unable to deflate would make them float upwards uncontrollably. It's plausible that you could have air creatures that fly using a similar technique, especially if you have lower gravity and/or denser atmosphere than earth. (A planet like the fictional Darwin IV would be a good place for this.) If you don't want straight out flight, you could have them use gas sacks to jump higher, or to make themselves lighter so they don't have to support their full weight while walking, or to assist with climbing or gliding.

Speaking of magic, an episode of Danny Phantom saw Danny's friends all get sick with an illness that gave them uncontrollable ghost powers. One character had uncontrollable levitation, making her basically stuck to the ceiling and unable to get down. Magic is nice because you don't have to make it physically plausible - as long as it follows its own rules, you're fine.


Rather than magic, you could go for a scientific basis.

When I was 12, I wrote a short sci-fi story in which the protagonist suffered a similar fate. In this case, he was a quantum theoretician who had discovered the physical basis of inertia. With certain energy fields, he could briefly suppress inertia over a small area.

Being a practical guy, he thought this was a great way to get rich, and he decided to design a new kind of vehicle braking system. Instantly stop a car and its passengers, with zero whiplash. He would make billions.

Of course, he had to prove it first. One prototype later, he was cruising down the street at a moderate 30 mph, and engaged the hyperbrake.

And the next thing he saw was the Earth receding from him at 400,000kph.

What he hadn't accounted for is that 30 mph he was driving at was only one tiny component of his motion vector. On top of that was...

  • The rotation of the Earth ~ 1,000 mph at the equator
  • The revolution of the Earth around the sun, ~ 66,000 mph
  • Our sun's local motion, based on local standard of rest, ~ 43,000 mph
  • The rotation of the Milky Way galaxy, ~ 483,000 mph

Stopping his inertia completely meant he was suddenly at zero velocity with respect to the fabric of space-time, not with respect to Earth.

We'll ignore the thermodynamic implications of where that energy went.

I had to make a decision as to whether he flew off the Earth, or through it. Both were intriguing...

  • $\begingroup$ But there is no absolute coordinate system with respect to space-time. But in any case, saying “the disease makes you stop relative to the CMB” is not a scientific explaination relative to “disease makes you fky off the Earth”. $\endgroup$ – JDługosz May 28 '17 at 7:29
  • $\begingroup$ I like this a lot as just playing with ideas about forced which we can't explain. What could "the physical basis of inertia" be? It sounds magic to me, but in the end I regard all science fiction as magic :) And what thermodynamic implications? Maybe "where that energy went" is that it destroyed a mass or masses instantaneously at the "origin" of everything underpinning his instantaneously stopped travel vector--near an empty edge of the universe. $\endgroup$ – r_alex_hall Jun 29 '17 at 21:22
  • $\begingroup$ @JDługosz The concept of spacetime as a nonuniform fluid seems relatively new. Even if we can't apply an absolute, uniform coordinate system to our Universe, the concepts of position and inertia still make sense experientially. Even hologram theory is correct. When I was 12 (35 years ago) the rubber sheet theory prevailed, and the universe seemed a much simpler place. I think for the OP's world, the idea of a disease which affects inertia could explain the "fly off the world" effect. As a vector... maybe quantum radiation, generated by experimental physicists at CERN. $\endgroup$ – Memetican Jul 1 '17 at 6:56
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    $\begingroup$ @r_alex_hall I think we can probably explain inertia as well as we can explain gravity, i.e. not especially well at all. Re- thermodynamics implications, it seems to me that such a large amount of energy, in the form of you moving through space at a high velocity, suddenly stopping would generate an enormous amount of heat energy. Conservation of energy. My guess would be an explosion, but I never went past high-school physics. Thermodynamics wasn't a big part of it. $\endgroup$ – Memetican Jul 1 '17 at 7:00

Ever pour water into a glass, then pour in oil? The oil get displaced and rises to the top of the glass. Not because gravity isn't affecting it, but because the water is more dense and pushes past the oil molecules. So as for a disease (something that could even affect inanimate objects), it/they could be affected by a disease of density; that is, their flesh and bones becomes less dense than the surrounding atmosphere, causing them to rise above it. If the requirements are that they would completely subvert gravity, then this might not work, but if "falling toward the sky" is the only requirement, density could easily be your solution.

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    $\begingroup$ I don't see how one could have his body be made less dense than air and still be itself, let alone survive. $\endgroup$ – Keelhaul May 24 '17 at 14:57
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    $\begingroup$ @Keelhaul So magic is an acceptable answer and something with some basis in science is downvoted? Makes perfect sense to me. $\endgroup$ – Tim S. May 24 '17 at 15:21
  • $\begingroup$ @ Tim S. : First off, I'm not the one who downvoted it. I merely pointed that your answer, while respecting a physics principle to explain the rising of various stuff, wasn't making sense considering the "people still live" part. $\endgroup$ – Keelhaul May 24 '17 at 15:25
  • $\begingroup$ @Keelhaul the comment wasn't geared toward you (I see how that could be thought) but towards the downvote in general -- but either way, my point is that when "magic' is a viable option, the idea of having something be distorted in a way that would cause it to float, yet not die, is definitely viable. I wasn't saying that this can be done with only science, I was merely stating that a solid scientific principle could be used to explain the floating itself. The rest could be anything, like magic. $\endgroup$ – Tim S. May 24 '17 at 15:46

It is possible (kinda). If something really heavy (with stronger gravitation than earth) came close enough. Thing wouldn't have to be heavier than earth - being more condensed would be enough as we would be closer to it's center of mass. This would have different effects on people and things further away. On other side of the planet gravity would feel a bit stronger actually

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    $\begingroup$ -1 simply because I'm pretty sure if it was massive enough to pull people and things towards it, the effect would not be limited to just a few people/things, like the question has requested. I imagine it would also cause considerable damage to most buildings (which aren't used to or designed for dealing with upwards gravity) and even the Earth's surface. I don't think you can really give a solution to this problem involving gravity, unless you invent some science which manipulates gravity in an unnatural way $\endgroup$ – danl May 24 '17 at 12:42
  • $\begingroup$ It's the only real on scientific facts based solution (as far as now-days physics goes). I don't get what would be a good answer if this is not? Saying: "aliens take them for probing"? $\endgroup$ – NoOorZ24 May 24 '17 at 12:52
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    $\begingroup$ it's not that your answer is entirely wrong - you've answered "how to cause objects on earth to fall upward" relatively well, the problem is that the question is specifically "how to cause some (not all) objects on earth to fall upward", with a set of criteria that your answer doesn't match. Your answer is more science and fact based than any answer that really can be given to that question, but the point remains that you didn't quite answer the right question $\endgroup$ – danl May 24 '17 at 12:58
  • $\begingroup$ My answer wasn't meant as solution it was meant to show what's closest we can get to solving this problem. $\endgroup$ – NoOorZ24 May 24 '17 at 13:01
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    $\begingroup$ Any object sufficiently massive and close enough to yoink things up off the surface of the planet will be two things: 1) incredibly bleeding obvious and not called a "disease." and 2) cause the death of the planet as the planet would be inside the roche limit of this new massive body (and probably in short order). $\endgroup$ – Draco18s no longer trusts SE May 24 '17 at 15:08

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