• mumblerfish@lemmy.world
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    10 days ago

    Well, “nothing” comes with caveats. I never did the calculation myself but the principle is true: take a light and point it towards the right side of the moon, flick your wrist to the left. The edge of your light on the face of the moon – you have a very strong light – will travel faster than the speed of light. It is not nothing but it also does not contradict relativity. Some insists of calling it “speed of causality” instead because that will more accuratly describe what is allowed or not

    • Backlog3231@reddthat.com
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      10 days ago

      That isnt how it works. The speed of light is the speed of causality; it doesn’t have anything to do with light. Its just the fastest speed at which things can happen. Light, being massless, happens to travel at that speed.

      In your scenario, the light beam would just be stretched along its length and the 2D interface on the surface of the moon would just “lag behind” from your POV. But it would lag at the speed of light.