I've got a new invention which I think could revolutionize the transportation of people and goods: it's a teleport unit, which can transmit matter from one portal to another regardless of what is in between the portals.

Unlike most teleports, though, it isn't instantaneous. It takes exactly as long as it would take the item being teleported to travel in a straight line between the portals, at the speed the item was introduced to the portal: if it is introduced at 60mph, and the exit portal is 60 miles away, it will appear an hour later, still traveling at 60mph. The item being teleported doesn't seem to experience the time, but just sort of skips over it - it's instantaneous from the traveler's point of view, just not the rest of the world.

The problem is in the marketing of this. Obviously, I can't advertise it as being useful for getting to last minute business meetings: it'll take just as long as travelling in a straight line would, even if you don't experience that time. Testing has shown that people tend to feel a bit uncomfortable if they're travelling in a fast vehicle that goes through a portal where there is a jarring change of light/scenery, so I'm thinking of taking on the container shipping industry. My plan is simply to push containers through the portal, on rails, so the drivers never need to go through either way. I can't help feeling I've overlooked something though...

  • It requires a portal at each end, but doesn't draw power beyond what a reasonable electric socket could provide (it doesn't need a power station to run, but can't be set up off-grid really) - this is a continuous draw, so needs to be applied for the full period of transportation, to both ends. It doesn't vary power consumption based on whether anything is going through the portal or not though, nor on the mass of the transported items.
  • Haven't found any particular limit to how big the portals can be, but things being sent need to fit through both ends (well, technically not... But only the bits that do get transported...)
  • Portals can't be moved while active - offline portals can be moved and reconnected, but anything sent to them while they are offline is lost. They can technically send or receive items, but they will come out scrambled and possibly incomplete. To avoid this, both portals should be stationary relative to a large gravitational pull - all testing has been using the Earth as the anchor, since I don't have any access to space. Don't see any reason why it couldn't be relative to a star or other planet though. Probably makes them less useful for interplanetary travel...
  • If something is part way through a portal and stops moving, you get part of it sticking out each end, once the transmitted part reaches the destination. Not sure what happens if you then push from both ends... It seems unlikely to be good.
  • If the power fails or is cut off, anything in the portal (e.g. has entered at one end and not yet exited from the other) is lost. Not sure where it goes - haven't found anything that suffered this fate yet. Stuff pushed directly into to an offline portal just goes through the space the portal encloses (like an open door). Stuff pushed into a portal where the other end is offline is lost.
  • They are bidirectional. Can put stuff in either end, and it comes out the other end, assuming the power is kept on to both portals at all times.

What's the best way to utilise this invention to get rich?

  • 14
    $\begingroup$ Heres a question: at some point an object, say a human, is halfway in the portal and halfway out. Half of the human does not experience time and half does. So wouldnt anyone die from going into the portal as suddenly bloodflow is haphazard at best and much of your signals are lost? You could solve this with "the portal's effect will flow x meters through solid+liquid matter upon a portion entering the portal", so that a finger in the portal instantly protects the entire human. $\endgroup$
    – Demigan
    Oct 18, 2018 at 17:13
  • 20
    $\begingroup$ What happens if I hold I coin through in my hand for a moment, and then withdraw my hand? Hours later, my hand pops out the other side with the coin, and then someone swipes it, and now there's two coins? I think regardless of how you try to resolve that, you probably end up with causality concerns. $\endgroup$ Oct 19, 2018 at 0:03
  • 7
    $\begingroup$ You say the portals can't be moved, but in reality everything is always moving. Say you wanted to place portals on Diana or Mars. They are always moving, relative to the Earth. $\endgroup$ Oct 19, 2018 at 0:07
  • 16
    $\begingroup$ Can a portal be used by a second user when the first one is still in the process of going from sending end to the receiving? If yes - how are eventual conflicts on the receiving end resolved (an example - we have two portals 4 miles apart. One person enters the portal with speed 2 mph at 10 A.M., another person enters at 4 mph at 11 A.M. Easy math shows they'll both get to the receiving end exactly at 12 A.M. with different speeds - what is going to happen in such case?). Other question - are the portals uni- or bi-directional? $\endgroup$
    – Ister
    Oct 19, 2018 at 8:45
  • 7
    $\begingroup$ What's a strait line at the surface of a moving sphere turning around a star turning around a galaxy itself moving in the universe ? $\endgroup$
    – Kii
    Oct 20, 2018 at 13:00

33 Answers 33



A lot of money goes into making oil pipelines, and delays caused by protests and lobbying is making them more and more difficult to get built. If you can transport oil without dealing with all the points in the middle you will have many people willing to license the technology from you. You don't need to build or manage anything your self, just offer a license and receive billions immediately.


Pipelines, version 2:

Lets consider another big shortage in the world: Fresh water. Serious consideration has been given to towing icebergs to provide fresh water in parched areas. Lets do it the easy way:

Build a big portal, attach a nuclear power source underneath. Take it deep into Antarctica, drop it. It melts it's way down through the ice and comes to rest on the land deep beneath at which point it activates. Yes, it's in ice, not water, but given the pressures the ice is going through, probably at a high rate of speed.

  • $\begingroup$ It would be easier to put a portal at the mouth of a river where it enters the sea. $\endgroup$ Oct 24, 2018 at 13:35
  • $\begingroup$ @SherwoodBotsford If you didn't mind taking the water from there the same thing could be accomplished now with a small dam. We don't do that. $\endgroup$ Oct 27, 2018 at 11:36
  • $\begingroup$ Loren Pechtel: This actually has been proposed. The problem is the transport to where the water is needed. Water supply is easier if powered by gravity. Getting water from the mouth of the Columbia to the San Joaquin valley requires getting it over the coastal mountains. A slow teleport eliminates this problem. $\endgroup$ Oct 29, 2018 at 18:31

It will take a bit of engineering but it will soon replace air travel altogether.

I'm planning on a trip across the world soon and the worst part of that will be being stuck in a plane for ten hours. Being able to skip that time, even if it takes twice as much outside time would be fantastic.

The main advantage air travel has is actual speed and being mature.

A complex to accelerate some passenger pod to reasonable speeds (200-300 km/h) seems fairly trivial compared to a busy airport and even a single passenger plane, and fuel costs are trivial.

As the technology matures I expect the pod to exceed air speed quickly and for long trips it has the additional advantage of traveling in a straight line compared to the arc planes are forced to take.


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