# Would low-grade levitation be of any use?

Malcolm dreams one night that he can levitate and wakes up to find that he is still able to. He teaches others to do it and it becomes a world-wide craze. Soon nearly everyone can do it and Malcolm finds he is no longer the centre of attention. Can he or anyone else find a use for this levitation other than for fun?

Basic facts

Almost any human can learn to levitate to about 1 cm above the ground. The actual height is given by H = WP/M where H = height, M = mass and WP = willpower. Willpower can be measured by psychological tests.

Lateral movement is possible and almost frictionless but requires some form of propulsion - it obeys Newton's laws. On a slope you will not accelerate downhill but instead move at a steady speed according to the angle. If the angle is steep you may still be touching the ground. If it's too steep, watch out!

Skating doesn't work because of the lack of friction in all directions. (Edit: As has been pointed out, you could de-levitate, push off then levitate-and-glide. What I meant was that you can't push off with your feet while levitating)

Levitation is quite exhausting. The world record is 20 minutes and 2.3 cm.

If you fall from a height, your momentum will overcome your ability to hover so your injuries will be almost the same.

Question

Is there any conceivable application for this ability? (EDIT - Specifically in a way that would most benefit local populations or humanity in general. This could be measured in economic terms or in terms of, say, how the the invention of the wheel changed everything about civilisation.)

I exclude scientists developing an improvement in the future. I want to know if there is an application right now under the above conditions.

Answers to comments (ongoing, I will treat them one-by-one in no particular order. Remind me if I missed yours)

MonkeyZeus - If you are wearing shoes with thick soles then you will not rise unless you manage to levitate right out of your shoes. This is because the insoles of your shoes count as the ground while you are wearing them. The world record was achieved with bare feet and virtually naked.

Chronocidal - If you try to levitate whilst lying down, your head will rise until you are upright and then you will levitate the normal distance. Note: I've had to change this for consistency - I don't think it invalidated anyone's answer.

Dewi Morgan - An equal and opposite force on the ground does occur. It's just as though you are standing on it with your feet although more spread out as if you were standing on a large soft rubber ball.

Nuclear Wang - You do not accelerate down a (gentle) slope but you do move down it at a constant velocity (Think Lenz's Law). I have to check but I think the speed is proportional to the sine of the angle. When the slope gets beyond a critical point, you cannot maintain a small enough vertical distance between you and the surface. At this point a catastrophic failure occurs and you begin to accelerate.

Kamil Drakari - The only friction in a horizontal direction is from the medium you are levitating in. You cannot use will-power to move laterally. Otherwise it's just like standing on a very slippery surface except that you automatically remain upright.

Dewi Morgan - In a train, when the train starts to move you will tend to remain stationary so hold onto something. On a plane's wing you would simply be blown off unless you are fixed to it.

You can levitate over a liquid but it will be pushed downwards and away. You can 'float' over dense liquids (such as lava) once you have displaced your own weight.

M.Herzkamp - Yes it is definitely more exhausting to levitate a higher mass to a given height. You can compensate for a large mass by levitating a smaller distance.

• Comments are not for extended discussion; this conversation has been moved to chat. Commented Nov 15, 2018 at 22:19
• Chas say I am levitating one inch above the ground. Is there any reason I couldn't be holding a stick (think field hockey stick) and push along with it - so, simply exactly like punting in a boat? Commented Nov 17, 2018 at 4:30
• If the answer is "no" you're saying that, however, it's perfectly OK for my friend (simply standing on the ground next to me) to give me a push and I'll float along. Is that correct? Commented Nov 17, 2018 at 4:31
• @Fattie - Your assumptions are correct. You can punt and someone can push you. For any appreciable distance it's much more tiring to float than simply to walk. Commented Nov 17, 2018 at 16:57
• If I have paraplegia, can I levitate? Can I use levitation to stand up? And glide around? Commented Nov 18, 2018 at 18:04

I wonder how this would work for those with physical disabilities. Say someone who cannot use their legs is able to levitate. I assume levitation of a centimeter still applies to your feet even if you normally sit in a wheelchair. So someone who normally has to sit at half of their normal height and wheel around to move would now be able to levitate at their full height and move around even without using their legs.

Levitating instead of walking for even only a few minutes would be revolutionary for those who normally require a wheelchair/crutches/etc. to get around.

• Agreed. Even if it's just used for transitioning to/from a wheelchair
– Joe
Commented Nov 15, 2018 at 17:47
• Very interesting. In fact the levitation is measured from the lowest part of your body. You can still levitate if you have no legs. Your head is always at the top. Imagine someone dangling a rag doll by its head or in fact any doll by its head regardless of the shape of the lower body. Commented Nov 15, 2018 at 20:59
• Hrm - so not just a transfer of reaction force from the sole of your foot to a few inches below? At what point in the body is the upwards force applied? Like, what part does it feel you are being lifted by? Your chest, your head... a force distributed throughout your body? Commented Nov 15, 2018 at 21:33
• I would say that it feels like you are generating willpower inside your head. It's mainly concentrated there but kind of spreads to the rest of your body. In other words you automatically stay upright. Difficult to describe. Maybe like a human shaped helium balloon with a small weight fixed to the feet. Commented Nov 15, 2018 at 21:39
• I'm accepting this answer because it would provide a lot of benefit to a lot of people. Also it doesn't need much in the way of extra equipment or infrastrucutre. Pity it isn't real :-( Commented Nov 27, 2018 at 10:28

It seems to me that it would be pretty easy to take a run, start levitating and skid along rather than walking.

The benefit over roller skates is twofold:

1. It requires no equipment, so anyone can do it whenever they like.

2. You don't accelerate down hill. so presumably you don't slow down going up hill?!

Even if we disregard the conservation of energy loophole and take into account that it's still tiring to do. I think you would see a huge change in the way people got around.

This might seem a small thing at first, but after a while we would see huge changes in urban planning and environments to accommodate the change from walking to 'skidding':

• pedestrianise city streets as people can travel further to get to car parks, bus stops etc

• 'skidways' introduced to allow fast travel without crashing. Vertical poles to grab and swing around when exiting or cornering

• crashpads on walls at corners for people who go too fast!

• electromagnetic launch strips to start you off super fast!

• various skid-assisting devices, can you push yourself along or steer with a walking stick? Bags with wheels so you don't have to levitate them too.

• Comments are not for extended discussion; this conversation has been moved to chat.
– L.Dutch
Commented Nov 17, 2018 at 21:25

High speed transportation

Think mag-lev for humans, but magnets doing the pushing and the person doing the repulsion. Even with 15 mins of levitation time, this is plenty sufficient for moving people around the city.

Alternatively, small portable propulsion means could be provided for off-roading experiences, obviously with less oversight and control so therefore more risk of dying.

Free energy generation

If you don't accelerate going downhill, then there is missing potential energy somewhere in the system. Harness it.

• Comments are not for extended discussion; this conversation has been moved to chat. Commented Nov 16, 2018 at 4:05

It seems that ground level is all in your mind, hence the failure to accelerate downhill. This should allow you to perform some interesting rescue feats.

• Little Johnny too close to the edge of the dangerous cliff? Levitate out there to get him back without putting pressure on the ground.
• A sheep stuck on the side of a mountain? Again you won't accelerate down the hill so you're safe holding position without risk of falling.
• Little Johnny is a pain and he's fallen through thin ice this time. Again you can get out there without taking any great risk yourself.
• Horse trapped in a swamp? Again you're good to go.

Many of the difficult or inaccessible areas that once required specialist equipment or significant risk are now accessible.

We're not reinventing the wheel in the short term, as you've said it's exhausting in a way that riding a bicycle isn't, but we are reinventing the dangerous area rescue.

• How would you rescue the horse? You only have human strength and as specified, there is almost zero lateral friction. Also H = Willpower/Mass so trying to lift the horse would require an impossible increase in willpower. Commented Nov 15, 2018 at 12:30
• @chaslyfromUK, the usual ropes and straps would be required, but accessing the horse is much simpler. Good to go, not good to heave :) Commented Nov 15, 2018 at 12:33
• Awesome answer, I think you should point out a little more that you are just able to access the person/animal to be rescued rather then performing the rescue itself. I.E. if Big John fell through the ice now its a slow progress toward him with a rope to make sure your not rescuing the rescuer who also fell through the ice. With this - "quick hand me a rope....now pull!!" Commented Nov 15, 2018 at 12:41
• Per updated spec, reaction-pressure is applied to the ground, so you'd still risk the cliff/thin ice giving way. Johnnie dies in both cases, and I think the horse does too. Commented Nov 15, 2018 at 21:43

Traverse the minefields

You could also play "floor is lava" game but getting across area that may contain landmines is probably quite useful application. Use small electrical propeller to provide thrust.

• This is assuming the levitation doesn't have a reaction force against the ground -- otherwise the effect would be the same.
– 0xdd
Commented Nov 15, 2018 at 19:09
• It has the effect on the ground as though you are standing on a rubber balloon. Commented Nov 15, 2018 at 20:12
• Which would be no more effective at avoiding minefields than snowshoes - spreads out the force a little, but that's it. Commented Nov 15, 2018 at 21:44

## Military and Police applications

### Quick and quiet movement

Ever tried to move quickly and quietly as you approached a cults/terrorist/suspects bunker in the middle of the woods to rescue some hostages? Probably not, but as you can guess it takes a lot of time and a lot of work to make sure you are not heard as you get into position. Floating would would prevent a lot of noise when sneaking up and probably take near the same amount of effort. Even if it was only as far as someone could push you from the perimeter - time is a huge factor in this.

### Less worry about landmines and IEDs

The actual procedure from exiting a vehicle in Iraq, involved checking the ground to make sure you would not get blown up as soon as you put your foot down. Getting blown up by IEDs or landmines would be a lot less of a worry (and worth the effort) if you could hover. Even for just a short 5 minute area check, esp. if you were transporting a VIP and were only the first part of the team or in a police situation when approaching that same bunker from the first part.

• Watch out for gusts of wind blowing you off course though! It's a bit like driving a silent hovercraft but with no sideways control. Commented Nov 15, 2018 at 20:16
• In the updated spec, there is a reaction force applied to the surface you hover over. So in terms of force dissipation, it'll be no better than snowshoes. Loose leaves/gravel would probably still crunch, but less. Commented Nov 15, 2018 at 21:41
• @chaslyfromUK would you really be moved by gusts of wind? Of course, part of what keeps us in place when wind blows, is friction, but isn't the mass of the body much larger component of that? Commented Nov 15, 2018 at 22:36
• @DewiMorgan yeah, I went to work and missed the updates. Still any less force is still less chance to set off a device's trigger (remember IEDs vary in sophistication and landmines are sometimes set to go off when multiple people are on them, to maximize damage, so are not "hair triggers"). And a big advantage of the hover for approaching a place is you could hover then be pushed toward the target - way faster than the slow, careful approach while still creating less sound. Commented Nov 16, 2018 at 2:43
• @chaslyfromUK eh, usually I ask for clarifications with comments but I was about to get ready for work and rushed this - your updates don't invalidate it (make it less of an option but not invalid) - and I have some other ideas I'll add if/when I have a chance this weekend Commented Nov 17, 2018 at 14:09

Note: this is based on a previous version of the question, where the OP did not clarify some aspects which were assumed in the writing of the answer. The clarifying edits were made after the answer was posted.

• Cross bodies of loose consistency/poor grip (calm water, marshy ground, snow, ice, etc.)

When you now need a bridge to cross a river or a lake, or some kind of support to go on ice or snow, you can simply step on the surface and, while being above it, simply paddle or propel yourself on it. It saves the money needed for building pedestrian bridges, in the case of lakes/rivers.

• Perform actions on surfaces which cannot be walked on

Think things like maintaining a zen garden where you don't want to leave footprints or inspecting the 10 meter diameter mirror of a telescope without putting your boots on it.

• I'd add marshy ground, (fictional grade) quicksand, snow, thin ice, gravel and soft sand that can be hard going to walk on, and other generally unstable surfaces to that. Commented Nov 15, 2018 at 12:01
• surfaces which cannot be walked on: hot tar/asphalt (pushing rises flat when fixing a road would be a lot easier) Commented Nov 15, 2018 at 12:44
• ncbi.nlm.nih.gov/pubmed/9088360 - "The 'cost' of medical care of these slipping injuries was almost the same as the 'cost' of all traffic injuries in the area during the same time." Just people not breaking bones when sidewalks are frozen would probably be a decent benefit, and save on salting them. Commented Nov 15, 2018 at 14:53
• Also this guy wouldn't be in a bind: i.chzbgr.com/full/8531314944/h2A94E987 Commented Nov 15, 2018 at 14:53
• @millimoose. I'd have to guess that he'd figure out an alternative :) Commented Nov 15, 2018 at 17:04

It feels like, because of the curious no-downslope-acceleration rule, like we should be able to make a perpetual motion machine, but I'm not sure how that would work.

Essentially the hovering is just fancy rollerskates/maglev, apart from this one thing.

Normally, if you push something on rollerskates up a hill, it takes more force than pushing them on a flat plane, because you are storing potential energy in that thing.

And if you push it back down, it's easier, and you're recovering energy.

In this case, however, you gain no energy pushing someone downhill. That implies there's no gravitational force affecting you while you hover.

Consider a tramline, or cable car. One car goes up, one down. In the "up" car, people are requested to levitate. In the down car, they are requested not to. The down car will be "heavier", so the system can work indefinitely from gravity, so long as there are people wiling to help out.

However, since this takes work on the part of the passengers, and since infeasible amounts cannot be lifted this is no different in practice to a cable car that has pedals and asks people to propel it by pedalling.

[Edit: with clarifications, the universe doesn't act as if the mass is cancelled out, just that the reaction force is separated from the sole of the foot, as if on a small pedestal or stiletto heel. So the absence of acceleration downhill isn't due to no force; just that the force is vertical, with no tangential component. So, this cable-car thing doesn't work: the force is applied to the cable car just as if you were on rollerskates in the car.]

However, to continue the hypothesis that this essentially makes the person immune to gravitational effects within a short distance from local-ground... this could make space flight vastly cheaper, depending how it works.

Immediately obvious is that the mass of the astronaut does not need to be taken into account when accelerating, if they can levitate.

Far less obvious is that if the user essentially has no mass, and changing their local ground does not require force and hence a momentum change (which the no-slope-acceleration thing kind of requires in order to be possible)... then you can now launch astronauts at insane accelerations. You can subject them to explosive forces and they'd be invulnerable to them. The limit of acceleration would no longer be the squishies, but what the equipment could withstand. That means concepts like https://en.wikipedia.org/wiki/Nuclear_pulse_propulsion become reasonable.

This would of course introduce risk to the launch - what if the astronaut's levitation lapsed, even for a moment? They'd be a thin paste on the floor before they could blink.

[Edit: Again, the clarified mechanism means there's no protection from acceleration granted. Rats!]

More interesting yet, though, is what this implies about physics. The in-universe H=WP/m means that the units of willpower are the meter/kilogram, and every physicist on the planet will be looking at a way to make that unlock the energy of that mass.

Rearranging, you get m=WP/H. Combining with e=mc^2, you get e=WP * C^2 / H. At very low heights, you potentially have very high energy indeed.

[Edit: this bit remains. For a start, on a smooth and hard enough surface, you can lift near-infinite masses.

You can lift twice the mass, at half the height. In theory, if you can lift your weight by an inch, you can levitate a thousand times your own weight to a thousandth of an inch.

The downside is, the force is probably applied at your feet. In reality, it will work no better than a pair of rollerskates with a lift capacity of a thousand bodyweights: you can't pick up and carry that weight, it would crush all your bones, so having mental rollerskates that strong makes no difference to your real lifting capacity.

But the units of willpower being meters/kilogram (from distance = WP / mass) does mean that in any expression that involves mass, we can see if replacing it with (WP/Height) to try to exploit that exponential power of the distance. Again, though, I can't see a sane way to do it. It doesn't break physics in any way, and it doesn't achieve anything that a magnet or a wheel can't do for longer and cheaper.]

• I've clarified some of the rules since you wrote this. See changes at the end of my OP. You don't accelerate downhill but you move at a steady speed according to the slope. I was wondering about units. Maybe you could elaborate on the 'high energy' at low heights. I'm not sure of the implications. Commented Nov 15, 2018 at 20:26
• @chaslyfromUK Updated answer. I'm out of ideas, I think, given this cleaner, non-physics-breaking definition of the levitation. OK, it breaks physics, but only in that the reaction force is separated by a cm or two from the point of the force's application. And that doesn't seem exploitable, to me. Commented Nov 15, 2018 at 21:29

Skimming the answers, but it appears so far no one has thought of the obvious:

• Hold on to a car, levitate just as it drives off - there you go at high speed. This could be transport, or it could be sports
• Speaking of sports, kids and adults would invent a lot of new games and sports that involve levitation. Rotating sticks that you hold on to, then let go. For distance, direction, whatever.
• Take a long stick with you, levitate, push yourself off the ground or a nearby object with the stick - free movement.
• Instead of personal sticks, you can add handholds to walkways to people who are levitating can pull themselves along to add speed.
• and finally you can put the handholds on rotating poles so people don't even have to pull themselves anymore, just hold on and be pulled, then let go. Can be used for direction changes as well.
• Avoid making footprints, avoid slipping on a wet floor, avoid dirt on your new shoes - there are many instances where you would levitate for a short time to cross a terrain that you don't want to touch with your feet (or shoes).
• 1-2 cm is sometimes all you need to reach something on the top shelf.

Since it is an ability anyone has at any time anywhere, the main uses would be situational. It's like having a thumb - whenever it helps, you just use it without thinking much about it, the rest of the time you forget how special it makes homo sapiens.

• I like your 'situational' comment. I'm sure that's absolutely right. As soon as children were old enough to learn how to do it they would copy the adults and it would become automatic for them. Commented Nov 16, 2018 at 8:01

A rather more domestic option - laying carpet or painting or washing floors. These tasks are often a hassle when you have to ensure that you work towards the exit or box yourself in. Potentially much easier when you just levitate out.

I think it might have some limited possibilities in creating a sterile work environment if you don't have to touch the floor while moving around.

Also potentially theft and murder, being able to enter and leave somewhere without touching the floor would leave very little evidence and leave someone unsure which directions you moved in.

• You would have to push/steer yourself around though and that would leave traces. Wouldn't wearing moccasins be more effective? You can't use willpower to move horizontally, only vertically. Commented Nov 15, 2018 at 21:34

This would be fantastic for the elderly. Especially for elderly women. Now people wouldn't have to worry about falling down and breaking bones. You say that this power won't prevent damage from falling from height but what most of these people need is just a little help with balance. This effect is boosted by the clarification that your head rises first when laying down. That means people who are off balance will be set up on their feet.

• Of course you can't maintain the willpower at all times, it's very tiring. You could however use it it whilst negotiating difficult steps etc. I f your reaction time is quick enough you could save yourself whilst in the process of falling. Commented Nov 16, 2018 at 7:49
• @chaslyfromUK exactly. This wouldn't be a complete replacement for people that are constantly toppling over. It would be a safe guard against slips and trips. I don't think reaction time is a major issue since most people have time to try to regain balance and/or apply defensive measures like putting out a hand when they slip or trip.
– Erik
Commented Nov 19, 2018 at 17:35

OK the way I understand it is that levitating is like someone has put a thick invisible mattress beneath you. The downside of the mattress is sticky and sticks to whatever surface it's attached to. The top side is slippery like ice but it's where you're standing. The top side is also perfectly horizontal, hence no movement without propulsion. So far, not much violating of any physical laws (except the existence of the mattress itself).

So the question is - what applications would benefit from you not touching the ground, although force is still applied to the ground?

Well... I can immediately see applications in sports and entertainment (like ballet). That's cute but not exactly world changing.

Hmm... how about firefighters? Would it be a great boon to be able to float over ground that is too hot to walk on otherwise? Come to think of it they already have thick boots, and if the floor is too hot even for that... But maybe there is some application there.

One more idea - this could find use also in common everyday scenarios, like getting over big puddles or spills. Kids would use this while playing. Builders could use it to get over areas that should not be stepped on directly.

Hmm... what about rescues on ice? How big of an area does the weight get distributed on? Maybe this can help rescuers to get closer to someone who has broken ice and fallen in water.

• Yes, I imagine it would make roller skating redundant. You could de-levitate to push off and levitate to glide. Commented Nov 15, 2018 at 21:37
• P.S. The invisible horizontal slippery mattress is a good analogy for horizontal surfaces. However it doesn't deal correctly with slopes. Commented Nov 15, 2018 at 21:52
• @chaslyfromUK - Huh? Then how do slopes work? As I understand the mattress sticks to the slope (so it doesn't move), but it's upside is horizontal (so the mattress itself takes a shape like a trapeze or a triangle or something). Then you don't go anywhere (because you're standing on a horizontal surface) and the mattress doesn't go anywhere (because it's stuck to the surface). Commented Nov 15, 2018 at 22:01
• @chaslyfromUK - I can also see it working for parkour tricks where you slide on rails with nothing but your feet. Long jumps in skiing could be extended. You could probably invent new tricks for ball sports where you slide-crouch beneath an opponents grasp without losing any momentum.The triple jump would probably get a significant boost. I bet that martial arts could find a use for a sliding maneuver. Etc. Commented Nov 15, 2018 at 22:13
• @chaslyfromUK - Actually... just how quickly can a person go from not-levitating to levitating? In sports you need lightning-fast reflexes, can levitation fit into that? Or does it require at least a few moments of calmly gathering your mind focusing your willpower, and then slowly rising above the ground? Commented Nov 15, 2018 at 22:16

Levitation without upwards motion.

H = WP/M implies that energy is spent only once a mass is off the ground. A much more common application would be to reduce the weight of walking individuals while leaving them on the ground. A 250 pound person who effectively weighed 60 pounds would be very fast. Walking would become possible for people with weak legs who were effectively paraplegic at their normal weight. Morbidly obese persons or those with bad arthritis could get around much easier.

Even easier, one could levitate select parts of the body for improved appearance and cosmetic effect. This would otherwise require either plastic surgery or special garments.

• I can't quite get my head around this. There may be an ingenious invention in here somewhere. Certainly someone who is paraplegic could levitate but the problem of moving sideways would have to be tackled. The problem is, the instant you lose contact with the ground you are confronted with zero lateral friction. As for cosmetics, no-one has so far managed to selectively levitate a part of their body. Perhaps one day it will be possible. However the frown lines from the concentration needed might be worse than the improvement! Commented Nov 16, 2018 at 13:00
• P.S. Actually some light is dawning. I think you're onto something. Can you suggest some simple apparatus using present-day technology in addition to levitation (and fitting in with the physics) that would allow such people to walk. I think I can but it was your idea. Commented Nov 16, 2018 at 13:02
• Re paraplegics - this scheme would work for persons who had some residual function in their legs - adequate to push off the ground but not adequate to resist gravity or stabilize their weight. Re selective levitation of parts of the body - many, many persons use a special (under)garment for this every day. Really, a lot of people, in the real world. You will figure it out. Re simple apparatus - I am curious to read what you have devised! Commented Nov 16, 2018 at 13:46

Could you levitate over water? possible uses for coastal indigenous culture who was adept at would be for advanced fishing and hunting.

In a more technological culture, you could use it to avoid detection by pressure pad traps.

# Fantastic intercourse.

That would be the overwhelming advantage.

Also, if it's possible to do this form of levitation in your sleep, you could finally avoid the discomfort of beds - wrinkles pressing in to you, never being comfortable, etc.

# New forms of dance.

The society in question would pioneer fantastical forms of low-altitude dance.

Hauling things in constrained environments. You need at least two people, perhaps more depending on what you want to lift. Each person has special "shoes", they have no sole at all but a beefy top which is exactly matched to the wearer's foot. There is standard attachment point on the top of the shoes.

A contraption is clamped to the object to be lifted, it's resting on each person's shoes. It levels itself and lifts until the object being supported is no longer on the ground.

Note that the formula has no upper mass limit other than imperfections in the floor if they are not levitated high enough to clear them. The operator's strength is likewise irrelevant as no muscle is involved. Thus the amount each person can lift is limited only by how much pressure can be applied to the foot without causing damage--and note that since the support is perfectly conforming this will be considerable. (Yes, circulation will be cut off as the heart won't be able to pump against the load. For a short period this will not cause harm.)

Once the object is levitated it's pulled with a rope.

Sure, this is nothing that a crane couldn't do--but cranes need a lot of space. This can be done anywhere people can stand.