Have I missed any obvious applications of my portal superpower?

Question

One of the superpowers in my world is the ability to mentally manipulate portals. These portals are incorporeal, massless, 2-dimensional circles that connect points in space (akin to portals from the game Portal, except they are free-standing and can be telekinetically moved).

Portals effectively create infinite energy, which I'm not at all worried about. If that particularly bothers you, imagine they draw all the energy they need from 'the realm of magicness'.

Trainable/Alterable Aspects of Portals

These are the aspects of my portals that I can mentally alter. Most of these are trainable, allowing me to alter them further or more quickly as I gain experience.

• Portal size
• • Determined by the area of the portal cross section. Requires effort to make it larger or smaller than its 'base' size of a 30cm radius circle.
• Portal shape
• • Circular when unstrained.
• • Shapes can only be two dimensional.
• Portal movement speed
• • The greater the portal size deviates from its base size, the slower the portal moves.
• Portal rotation
• • Can be rotated in the x, y, and z axes.
• Max distance between portals
• • Around 50m without training

Portal Rules

Important

• Matter, light, and electromagnetic fields can pass through portals, but not gravitational fields.
• Portals come in pairs, with a back end and a front end that connect to one another. Most users only ever control one pair of two portals.
• Both portals will always have the same size and shape as one another.
• Portals will cut things at the atomic level, but not the subatomic level, meaning no boom boom and radiation.
• Movement through portals is relative, meaning if I enter Portal A at 10km/h relative to it, I will exit at 10km/h relative to Portal B. This means that even if I am stationary relative to the world, by quickly moving Portal A over myself, I will exit Portal B at high speed. See my crude drawings for a further explanation (Also feel free to ignore my misuse of scientific technology as I never took physics). You do no not feel acceleration or deceleration from this, as from your own perspective it is the world that is changing velocity and not yourself.
• Portals move relative to their user. If I start running, without controlling my portals at all, they will move with me. In cases where their relative movement would change after I exit a portal, they only begin to move with my new direction after I have fully exited the second portal.
• Portals can be rotated, causing the world through the portal to appear to rotate. This allows you to impart rotational or centripetal energy to objects moving through portals. See my crude drawing for a further explanation.
• Portal edges are effectively infinitely sharp cutting instruments, making them highly dangerous.
• Moving and altering portals does not strain the user or consume energy from their body.
• Other than when the portals first appear after gaining the superpower (the portals will appear snapped together), the portals cannot be created or destroyed. They will remain until the user dies, hence why snapping is important.

Less Important

• Portal pairs can be 'snapped' together, causing them to perfectly overlap, completely removing their functionality, as anything that passes through them will be teleported 0 distance. They must be actively 'unsnapped' to separate and be useful again. Snapped portals are completely invisible, only being detectable via the users proprioceptive sense.
• Portals are only visible due to the fact that they appear to be a circle leading to a different point in space. They don't have glowing edges or anything like that.
• Users have a proprioceptive sense of where their portals are, and the portals will instinctively stop moving before cutting their user, meaning a user can only cut themselves on purpose.
• Portals can be moved through one another, as seen in this video.
• Portals accelerate and decelerate instantly as they are massless (yes I know massless objects in reality always travel at c).

Combat Applications

Velocity Alteration

Instant Acceleration

By moving a portal over myself, I can almost instantly boost my velocity, without actually feeling any acceleration. By doing this over a body part, such as my fist, I can increase the power of my attacks.

Instant Deceleration

By slowly moving a portal over myself while I am moving at high speed, I can cause myself to exit the corresponding portal at a low velocity, effectively eliminating my kinetic energy. This is highly useful for preventing deadly falls or any situation in which I would slam into a surface at high speed. By doing this over an enemy's attack, such as their fist when punching me, I can reduce its impact.

Shielding

Portals can be used as impenetrable shields. Depending on how I position them, I can cause an attack to reflect back onto my enemy, or shoot harmlessly into the sky.

Flight

By carefully positioning myself through my portals, I can cause gravity to tug on me in opposite directions, allowing myself to fly.

Slicing

People and objects can be easily cut by moving a portal through them. Depending on the orientation of the portal, this might either cut holes out of them, or slice right through them.

Swinging Objects

By placing a snapped portal pair over an object held firmly in place, such as a tree or streetlight, and then moving one of the portals away, I can use that object as a powerful blunt weapon, as the part of it sticking through the portal will move with the second portal.

Range Extension

By placing one portal near myself and one near my enemy, I can significantly increase the range of attacks such as punches, by punching through the portal. Of course, I will have to be careful as my enemy can do the same.

Industry Applications

Free Energy

Hydro-electric

By placing one portal at the bottom of a dam or lake and another higher up, I allow water to flow continuously downward, providing energy that can be captured via a turbine. The output is limited by how large I can make my portals, and how far apart I can place them. This could theoretically be done with any fluid, or even something like sand.

Magneto-electric

By placing by portals in such a way that I allow a magnet to continuously freefall, I can induce a current in metal coils surrounding that magnet.

Direct Turbine

Placing the shaft of a turbine through a portal and then rotating it lets you directly power the turbine. This can produce enormous amounts of energy as the turbine can be made as large and heavy as possible, and spun incredibly quickly.

Digging

Portals allow you to move massive amounts of material very quickly. For example, you could dig a massive hole in the ground by moving one of your portals through the ground, with all the material that enters it falling out of the second portal.

Construction

Careful control of portal shape and size could let you cut precise objects out of stone, metal, or wood.

Transportation

Portals allow you to freely move material from one area to another, but this is significantly limited due to the portals' range and size.

Non-combat Applications

Air-con

By placing one portal near myself and another notably below myself, air will blow out of the one near me due to differences in air pressure, creating a refreshing air current.

Watergun

By placing one portal in a body of water, water will begin to pour out of the second portal. This is effectively the same as the hydroelectric energy generation concept, but on a smaller scale and just for fun.

Looking around corners

I can peek a portal around a corner instead of my head, allowing me to look through its pair.

Answer 1

Covert ops

Place your pair of portals before a wall or a building, then move one of them sideways into/through the wall parallel to its plane, so it won't cut a thing. Once the portal is "in", and the view-through is not obscured, you turn the inside portal parallel to a wall and place the outside portal close to the outer surface of the wall you're about to penetrate. Hello portable hole, you focus on locking down both portals and transfer in and out of the room. Afterwards, eject the inner portal the same way, leaving no trace on how did you enter and exit the protected area. You can use such technique to reach into enclosed devices like safes or vaults. Combine with "slicing" if you need to eliminate surveillance or guard.

Swap gun

Position your portals side by side with "blue" surfaces facing one side (the placement is correct if an object that's thrown from your side in one of the portals ends up on another side), then toss both portals forward with maximum speed attainable. Whatever matter is located forwards would get swapped between two 3D tunnels made by portals' edges. This would effectively kill any living creature that would have its head happen away from its body. Once at maximum distance, shift them sideways and pull back towards you, creating another pair of swaps.

Ultimate shielding, reflective shielding

Position your portals side by side (making them square if the user is able, to reduce the risk of someone hitting between them) so that the object thrown from your direction would get tossed back. Release control and position yourself between whatever is being protected and the enemy. Anything hitting the protected area would get tossed back at the same speed. HEY YOU, CATCH! If protecting against shelling, turn both portals so that the outer side is facing upwards at an angle.

Emergency catapult

If the portal user is in a freefall, he can position the portals like in Reflective Shielding, but below themselves and parallel to the surface, then exert control to lock them in position. They would then get thrown up and forwards from the projection. Once the user starts getting teleported, they can release control so that the portals would resume moving with them. This can allow the user to both escape death by freefall, alter the vector of their fall by turning the exit portal relative to the entry portal, and potentially also to avoid incoming fire.

Invisibility

This would require the user to have rather large and close set of portals. Position your portals at both sides of yourself, parallel to each other, and occasionally rotate them as a whole. The outside user would see objects behind you being one inter-portal distance closer while you are between them and the observer, but won't be able to see the user or actually interact with them because any force applied to the entry portal would just travel to the exit portal, leaving the user unharmed. The downside is that the user would be surrounded by "infinite" sights of themselves on both sides and unable to see what's there on the side.

As a side application, the user could scratch themselves on the back without external help or twisting their arms too much. Just face one of the portals and reach the back visible through it.

Kidnapping

Pull one portal under the target in the floor's material, the other at destination at the ceiling, then raise the first portal encompassing the person. It will fall right into your arms. Surprise!

Tectonic weapon

Pretty easy. Aim one portal at the enemy, then toss the second portal down flat. The enemy would have a faceful of rock, and the planet would have a deep well. If done deliberately, the well could turn into a volcano, adding insult to injury. If the user would turn the second portal midway, the well would become a cave, so this application could be used to make subway tunnels. And mountains.

There should be more, as this question asks for fantasy, as in "use a thing in unintended purposes".

Answer 2

In most game systems I have been involved in, the game master has a "cheese detector." This is a process whereby any aspect of the game that "makes swiss cheese" of things gets ruled out. Portals are usually on the list pretty quickly.

First, the only "downgrade" to portals that I have been able to detect. Your idea of peaking around a corner does not work. If the light you want to see can reach you, so can your opponent's ranged weapons.

The over power (OP) of a portal comes from the range it can open over, and the different conditions that may apply at the ends. You have touched on a few of these, but consider a little more.

Put the exit end of the portal horizontal and elevated over the entrance end. Exit facing down, entrance facing up. An object placed between will fall. Into the entrance and out of the exit. It drags the air with it. A one ton boulder (roughly 1 yard by 1 yard by 15 inches for most rock, or for metric folk, 1 meter by 1 meter by 35 cm) would then build up a down-rush of air and boulder that had no limit. Leave it there for 20 minutes or so, then turn off the portal so the boulder hits the ground. It creates a crater some miles across. You would need to open another portal to get out of the blast radius.

Put the exit end of the portal pointing at the village you are angry at. Put the other end about 100 yards under the surface of a lake or ocean. The pressure at that depth is round-about 10 atm. That's high for a fire hose, which is typically only 4 or 5 atm. If the portal were wide enough to walk through, you can wash away the entire village in a couple minutes. Or you can put out a quite large fire if you are inclined.

Put the exit end at extreme altitude, say 50 miles. The air pressure is quite low there. The entrance is then a very large vacuum cleaner. A portal wide enough to walk through will have round-about 50 tons of air pressure acting over it. And if the opposition lives through being vacuumed up, then they are pushed out of the portal at extreme altitude. And even if they live through that it takes them considerable time to get back to the fight. Felix Baumgartner took about 10 minutes for his fall from the stratosphere. So, probably the fight is over before they bother you again.

Depending on how difficult it is to navigate placement of the ends, you can extract things from vaults. Portal in. Open the exit portal. Start shoveling stuff through. You only have to move the stuff you are extracting far enough to get it into the portal. If you can move the portal ends around that might only be a few inches. The entrance can be horizontal so you can just tip over shelves such that they fall in the hole. You could clean out tons of stuff from a vault in minutes. Then you could use another portal to fill the vault with surprises of whatever type you please. Ocean water as previously mentioned. Fresh cement that will harden shortly. Farm waste. You name it.

The opposition has a castle of some kind. Any nasty surprises you have can be delivered directly inside the wall. The water jet just mentioned is just one example. Getting bored? Build a very large pile of wood, hundreds of trees. Set it on fire. Put the entrance portal in the very center of the fire and the exit inside your opposition's castle wall. Open a second portal of the vacuum cleaner type, drawing large quantities of air through the fire portal. It's a huge blowtorch.

Portals are massively OP. The "cheese" factor is too high.

Answer 3

Tactical Nuclear Weapons for Everyone!

At least, everyone who can make a high altitude portal, or has access to a vacuum tank.

A "God Rod" is a tungsten bar, dropped from space. It delivers the power of a small yield nuclear blast, with none of the messy isotopes, with solely kinetic energy to create the blast.

A portal user positions one portal below the other, in a vacuum, and drops a heavy weight through it. You leave it falling, to get to some absurd velocity, then move the lower portal, either pointing it towards a target or just straight down. Boom, instant, colossal explosion.

It needs to be a vacuum, because terminal velocity is an issue.

Edit: It's definitely a problem that this is tough to aim. However, giving the average portal user the ability to blow up a sizable section of a city, even at the cost of their lives, is a significant power.

Answer 4

Another answer stated that this device is uber OP, and I think that is an understatement.

Time Travel

You didn't explicitly state this, but the real-world implementation of such a portal would be via direct manipulation of the graph structure of reality (the so-called Wolfram Manifold) to disconnect and re-join disjoint sets of spacetime points directly to each other. As such, objects entering one end of the portal would necessarily exit the other portal instantly, i.e. with exactly 0 transit time in between. According to General Relativity, if your portals can accelerate, this means that in certain frames of reference you can send a signal back in time. While a 50 meter maximum gap between apertures doesn't seem like much, this effectively allows for time travel up to around 16 microseconds into the past.

Instantaneous Computing

Combine multiple portals and technology (such as a computer that can perform hundreds of instructions in 16 microseconds) and you can essentially perform any computation instantly by setting up a feedback loop where each CPU performs some instructions and sends the results a short time into the past as the starting point for the next computation. At a minimum this would probably require at least two people working together (at least at the start).

Creating Pocket Spaces and Universes

Other answers have mentioned shields and invisibility, but with the right configuration of portals, you can actually effectively causally disconnect part of the universe from the rest of the universe. To make this disconnect you only need another portal to snap together across the aperture of this configuration. However, I'm not sure if this would be wise because, even assuming you found a way to reconnect this pocket space back to the universe, the instant it is causally disconnected from the rest of the universe it may undergo spontaneous inflation due to the absence of any quantum fields around its periphery.

Automate the increasing power of portals

Effort should be made to expand the limits of the portal. Not only to increase the maximum range and to decrease how small the portal can be, but also to increase the number of portals that can be simultaneously controlled, either individually or as a group. Creating a human-technology interface should be a high priority to automate tedious tasks such as collectively controlling a large number of portals. As this is a super-power if you can't train one person to manifest multiple portals you will be limited to the number of people who have this power, so it will be important to either find a way to increase this number, or - especially if you are hard capped at one portal per person - the speed at which the portal can be used. Since portals are mass-less moving them at the speed of light should cause no "doom" effects while still giving the practical appearance of a large number of portals. With enough computational power (see: Instantaneous Computing) and and two people with two portals working together, the ability to discard non-useful experiments (see: Time Travel) allows for experimentation with control over the portals so as to advance the effective power (or control over the portal) to near its physical limits within a reasonable amount of time.

Filtration and Mining

Micro portals can be used as filters. Since they can slice through molecules but not atom you can use these filters to mine for precious elements by setting the aperture size to allow only specific sized atoms to pass (with dual filters for instance first the first to allow only everything smaller than the radius past and the second to only allow everything just larger). As mentioned before, with fast enough automated portals we can also simulated multiple portals since what we are filtering isn't moving relativistically.

Sensors

Two automated micro portals moving at high speed can effectively sample various physical parameters across a specific volume, allowing for a reasonable model of that space to be assembled.

Making a Consciousness Fail-safe

With micro portals we can combine most of the features of a pocket universe in a practical way, if you don't mind shedding all your humanity and becoming one with the machine. At first, one's body would move into a pocket universe along with the interfacing machinery, with a sub-atomic sized portal specifically to allow a high speed information pathway in between the pocket universe and the outside universe. Outside the pocket would be receiving machinery acting as the user's avatar, sending sensory input through the portal and receiving commands from the portal instructing it what to do. In the event of this shell's destruction the user would be unharmed and could extrude a new shell as needed. However, over time the user would continually upgrade the internals to put the parts that could wear out outside in the shell until their consciousness remained, but their physical body had been completely replaced by pure computation.

Answer 5

Non-orientable portals

When you create a portal pair, the two circles appear "snapped" together. But there's two ways you could make the snapping happen such that things passing through the portals "teleport 0 distance". In the first, most obvious case, you could enter the portal going left, and exit the portal going left. In the second, less obvious case, when you enter the first portal going left, you exit the second portal going right. This second case is an example of a non-orientable wormhole. If this is possible, objects passing through this wormhole would swap chirality, which has some non-obvious consequences.

Antimatter production

Most pertinently, in quantum physics, particles which switch chirality also negate their charge; ie. matter passing through the portal will become antimatter. So, if non-orientable wormholes (a case not explicitly covered by your rules) are possible, antimatter becomes very easy to produce.

Intersecting portals

Under the rules as written, portals can overlap while coplanar. Nothing written prohibits portals from intersecting, however, which leads to some interesting applications. If this is possible, some interesting applications emerge:

Finite closed surfaces

Imagine two parallel portals, like in the video game Portal. If you go down far enough, you pass through the bottom one and end up at the top. Now, imagine that there are three pairs of portals instead, so if you go left, you exit on the right, and if you go forward, you exit to the back. If the portals are big enough, and they intersect with each other, you've formed a closed surface. No matter which way you go, you'll be stuck inside this cube, and there's no path that exits this cube. Now, the actual minimum number of portals needed to do this is 4, if they formed a tetrahedron rather than a cube.

This has some useful applications.

Compressing stuff

What if the portals move closer together? Then the closed volume will end up getting smaller, but there's no way for any matter to escape. This allows you to compress stuff inside this volume. You can easily compress gasses, liquids, solids, etc. High-pressure chemistry becomes easy. A couple people with portals and a bag of charcoal can make diamonds. A couple of people with portals an a bottle of water can compress the water so much that the hydrogen inside of it undergoes nuclear fusion.

Containing stuff

If there's something dangerous, simply put it inside a closed volume and it can't escape while the portals are there. A bomb? A couple of portals later and the explosion is caught inside a space until everyone nearby is evacuated, and then the pressurized gasses and fast-moving shrapnel is slowly leaked out through a tiny hole at the bottom into a mound of sand. Since people's portals last after their death, a couple of people on their deathbeds could work together and store away a small volume of nuclear waste forever, for a nice inheritance for their next of kin.

What if we didn't bend the rules?

Optics

Portals can be used to redirect light with perfect efficiency, without chromatic aberration and the like. It can be used to change the polarization of light, too. So they can be used for anything that needs to precisely redirect light (like laser laboratories or microelectronics fabrication) or anything that needs to change the polarization of light (like laser laboratories, movie theaters, and microelectronics fabrication).

Topological defects

A pair of portals can be used to make a solid ring that's 720° around, as opposed to 360° around. How is that useful? Dunno, but it's cool

Precision

Human hands shake imperceptibly. If you have any of a litany of diseases, they also shake perceptibly. Portal control might have significantly more precision than human hands, so it's possible that precision work might be better done by using a couple of portals to hold things steady. This is useful in things that require precision work, such as mechanical watch making and making circuit boards.

Particle accelerators

One of the limiting factors of powerful particle accelerators is that they need to be a circle. You need to move particles in a circle in order to add enough energy to them to do certain bits of science. But moving particles at relativistic speeds through a circular particle accelerator is also wasteful, because you need to redirect the particle so that it follows the circle rather than goes in a straight line. Furthermore, when you redirect the particle, it emits synchrotron radiation, losing energy. Using portals, this limitation can be removed and you can use a short straight particle accelerator and still accelerate particles to tremendous amounts of energy.

Answer 6

Use Your Portals to Make Your Attacks Unstoppable

Many methods of avoiding an enemy’s attacks in hand-to-hand combat relying on blocking or parrying the opponent’s weapon. So use your portals to make this impossible. An enemy’s shield is useless because you can move the exit portal behind their shield, and the entry portal in front of it. This would allow any weapon to travel straight through their shield. And this wouldn’t only apply to shields either. Got a pesky group of enemies hiding behind a rock or wall with bow and arrow, or crossbow? Position your portals around their cover, and open a hole wide open in their defenses. Pick them off one by one, while they’re exposed trying to reload. And you wouldn’t even have to move from your position. Assuming your “front end” “back end” language in your question means that these portals can be unidirectional, this would also mean that your enemies couldn’t fire at you through the portal either, so it essentially makes your portal configuration a shield that negates your enemies’ shield’s.

Use Your Portals For Creating a Decoy and Confusing Enemies

Since your portals pretty much look ordinary with no defined edge except the view is whatever is in front of the entry portal, use these to create an image of yourself on both sides of your enemies position. Place the entry portal in front of you, and the exit portal in the other position where you want a decoy of yourself (or something else). Watch them panic trying to figure out which one is real, and (again assuming they can be unidirectional), stand in the open in complete safety as none of the projectiles they shoot at either can penetrate the portal (and if they shoot at the entry portal, their arrows will hit them from behind when they leave the exit portal). Take your time closing in on them for maximum scare factor.

Answer 7

Sanitation

No one is going to transport poo for miles any more. All manner of building regulations disappear, as pipes (for sewage or potable water) can just come out of a portal. In fact, if portals are strategically situated you need never use a normal toilet again.

Poo where you like, reach in and grab the paper, wipe, throw paper into portal, reach for specific spot in portal, wash hands, done.

Sex

I don't 100% know which of the million and one perverted sex applications portals will be used for, but they will be used. Dicks poking through portals will feature. Multiple strippers can burst out of one cake. I actually hate all this degeneracy and have reservations about mentioning it but it blatantly will happen, and have huge societal effects.

Contraceptives

Tangentially related to sex. Hard to get pregnant when semen is being sent straight to the ocean. Drunks still manage it somehow.

Real estate - overlapping buildings

With some careful portal arrangement, you could have 10 or 20 houses all 'in the same spot', with portals for windows and doors. The possibilities for skyscrapers are endless; have the elevators go through portals to separate spaces that have window portals to other places.

Real estate - megastructures, dynamic houses

You can now build buildings of basically infinite size in modular fashion. Why transport to see Aunty Doris when you can link your houses together for a week? Communes no longer form and collapse, they just wax and wane, ebb and flow.

Fashion

Strategically placed portals allow for all manner of fashion dodges. Women with big feet now all fit into tiny shoes.

Caesarian sections

Mum goes into portal. Baby goes into smaller portal 2mm in front of other portal.

Cat videos

If you thought cat videos are funny now, wait until portals get involved!