In Portal, using the portal gun to get to the moon is the obvious space travel usage, but I think people are overlooking how it’d let you trivially break the rocket equation.

Hell, you could build a >1g torchship using nothing but the ocean.

  • Foone🏳️‍⚧️@digipres.clubOP
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    10 months ago

    Portal 2 does establish that the portal-placing shot moves at the speed of light, but that just raises the question of how fast you move through the portals themselves.

    It basically can’t be slower than light, or you’d chop yourself in half if you moved halfway into one and then backed out.

    So it has to be lightspeed: which means, if relativity is still correct, that it’s also a time machine.

    • Jay Blanc@blan.cc
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      10 months ago

      @foone@digipres.club There’s a Cave Jonson voice line that mentions the possibility that testing the ASHPoD may involve “trace amount of time travel”.

    • Gorro_Rojo@qoto.org
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      10 months ago

      @foone@digipres.club i think 1) what travels at the speed of light is the shot from the portal gun to the surface

      1. there isn’t a delay from going in one portal abd going out the other, it being a pseudo-wormhole kind of situation
      • Foone🏳️‍⚧️@digipres.clubOP
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        10 months ago

        Anyway once you’re flying around the universe with your FTL portal-rockets the next question is what happens if the two ends of a portal are moving at different speeds through time. What if you drop one end into a black hole?

        • Webster Leone@meemu.org
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          10 months ago

          @foone@digipres.club My first thought was the Stargate thing where the effects go through the portal, but they didn’t have the other in a black hole, just near it.

          Would that make the portal one-way? Would it allow things to escape the event horizon? Would a portal even be able to go into one? What makes a surface capable of holding a portal? Would those properties cease in a black hole? Interesting questions.

        • Foone🏳️‍⚧️@digipres.clubOP
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          10 months ago

          And what if you put one end on an enemy planet and the other end in low orbit around Betelgeuse when it finally goes supernova?

          How many gamma rays will come through a hole in space about a meter across?

            • Foone🏳️‍⚧️@digipres.clubOP
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              10 months ago

              @susul@misskey.heonian.org I was thinking that the portal would be very short-lived, because the surface you placed it on would be quickly destroyed, but there’d be a short period where the initial gamma rays make it through.
              but yeah, if you can somehow keep it open longer than milliseconds after the instant of the star’s collapse, you’d absolutely wreck anything near the endpoint

            • Foone🏳️‍⚧️@digipres.clubOP
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              10 months ago

              anyway so there’s a point in Portal 2 where you fire a portal at a surface that’s far enough away that there’s noticeable light-speed delay before the portal opens, right?

              but is that based on the distance between portals or the distance from the gun?

              • Foone🏳️‍⚧️@digipres.clubOP
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                10 months ago

                like, in the game’s specific scenario, the distinction is irrelevant, but the portal gun is mobile after all. what if you set up a portal on earth, then hop in a rocket to pluto, then when you land, you fire it at the surface of pluto.
                The distance between the gun and the surface is minimal, but the portal pair you just set up is about 5 light-hours long.

                Does it take 5 hours for the portal to open? or does it open instantly?

                • Foone🏳️‍⚧️@digipres.clubOP
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                  10 months ago

                  anyway the fact the aperture science facility extended so deep underground in portal 2 was interesting.

                  hey, you know what a very deep underground facility would be real useful for? dropping stuff through portals and having it fall a long time, accelerating as much as possible.

                  I bet there’s a borehole we never see that’s just top to bottom and has as much atmosphere as possible evacuated from it, to lower air resistance

                  • Gif@eattherich.club
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                    10 months ago

                    @foone@digipres.club Fun fact: holes like this are also useful for testing the effects of microgravity. NASA maintains several near Cleveland for studying the effects of microgravity on fluids like air, water, plasmas, etc. IIRC you get useful results until you hit terminal velocity

                  • Grant Gould@hachyderm.io
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                    10 months ago

                    @foone@digipres.club Why even bother evacuating the atmosphere, that’s probably how they manage to heat the whole place :-)

                  • Michel Jansen@masto.nu
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                    10 months ago

                    @foone@digipres.club as long as you have two portals set up in a loop, would the actual distance between them matter at all? You could just put two portals 1nm apart in a vacuum and create an infinite accelerator. Then move the exit portal and BOOM

          • Michelle Hughes@a2mi.social
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            10 months ago

            @foone@digipres.club

            In @cstross@wandering.shop 's Glasshouse, they would drop one end of a very small portal into a blue giant star and the other end over to some kind of power plant, and they’d have all the energy and all the power they’d ever need.

    • Amikke@qoto.org
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      10 months ago

      @foone@digipres.club the portals connect space, you don’t move through them at the speed of light, you move through them at whatever speed you move in the space around them since they’re no different than any other plane cut through it.