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

    BTW, as a variant on the kzinti lesson, the portals are extremely dangerous as a weapon, because of how good they are as a weapon.

    Ignoring the obvious ways to fight with them like opening a portal on the enemy’s hull, shoving out a nuke and then closing the portal…

    You could also just have a rock that you’re letting accelerate to arbitrary speeds in a vacuum. That’s free unbounded kinetic energy, the only limitation being the “charge” time.

    • StenPett@mstdn.games
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      10 months ago

      @foone@digipres.club I recall Peter F. Hamilton doing just that in one of his books. The nuke part at least. Not sure about the space rock yeeting.

    • Foone🏳️‍⚧️@digipres.clubOP
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      10 months ago

      This isn’t a ship-destroying weapon, this is a civilization-ender if not planet-killer.

      You’ve got a projectile moving at a significant fraction of the speed of light. This is a relativistic weapon: it’s going to hit harder than if it was a nuke.

      • Foone🏳️‍⚧️@digipres.clubOP
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        10 months ago

        You can also make it bigger by not using a roughly round rock and instead using a long rod of the densest material you can get your hand on.

        But mass you pay for, speed you don’t.

          • Foone🏳️‍⚧️@digipres.clubOP
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            10 months ago

            But yeah this is the ultimate doomsday weapon. You can accelerate indefinitely for free, you just have to wait.
            (and if you can put your portals in orbit of a more massive object, you get faster acceleration than 1g)

            So you don’t need more than a portal gun, a tungsten rod, and some time to blow the atmosphere off a planet.

            • Linus@schreibt.jetzt
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              10 months ago

              @foone@digipres.club how do you make sure it’s aligned right? It’s no good if it drifts to the side and hits the edge of the portal, maybe already at a dangerous speed, at your weapon site rather than your target

              • Foone🏳️‍⚧️@digipres.clubOP
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                10 months ago

                The Nihilanth could teleport an entire army to earth, the combine can conquer a planet in hours, the g-man has control over time and space, but Cave Johnson’s invention could put a hole in a planet

                • Guy@hachyderm.io
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                  10 months ago

                  @foone@digipres.club boring “explanation” that the energy which can cross a portal is limited by the power of the portal generator - so you can only accelerate to c if your generator can output that much juice - it’s not free just super efficient

                  • Foone🏳️‍⚧️@digipres.clubOP
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                    10 months ago

                    There’s also the gravity interaction: an infinitely falling object that never reaches the bigger body is also accelerating the bigger body.

                    Your forever falling object is shoving the earth upward, very slowly. That could matter in the long enough term… But it seems kinda meaningless compared to the other ways you could use a portal.

                    Still, might be handy if you need to adjust the orbit of a planet and are willing to wait.

          • ComradeGibbon@mastodon.social
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            10 months ago

            @foone@digipres.club So with something 4 times bigger than the Tsar Bomba we could get a bag of cat litter to 90% the speed of light?