Comment on I can whistle at the speed of sound

• PythagreousTitties@lemm.ee ⁨3⁩ ⁨months⁩ ago

  But I never use my vacuum. Might as well fire a laser at it!

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• dev_null@lemmy.ml ⁨3⁩ ⁨months⁩ ago

  It’s still travelling at c, it’s just bouncing around the medium’s particles on the way. It arrives later because it’s not going in a straight line.

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  • qjkxbmwvz@startrek.website ⁨3⁩ ⁨months⁩ ago

    I don’t think that’s a great way of thinking about it. I think you’re describing something more like scattering — or maybe absorption and stimulated or spontaneous emission — which does indeed happen, but is distinct from the index of a medium.

    If it were indeed “bouncing,” optics wouldn’t really work, as any n > 0 medium would cause the light to go every which way.

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    • SirSmokeAlot@lemmy.ml ⁨3⁩ ⁨months⁩ ago

      If you fire a laser that goes first through vacuum, then through a lens, then again in vacuum, at what speed is the light travelling on the other side?

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      • qjkxbmwvz@startrek.website ⁨3⁩ ⁨months⁩ ago

        It’s same as it was at first. The speed of light depends on the index of refraction of the medium it’s in, but doesn’t depend on its “history.”

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• Evil_Shrubbery@lemm.ee ⁨3⁩ ⁨months⁩ ago

  Yes, ofc - but we’re talking about a weapon here, the air is implied as a medium, and the very-near-c with it.

  But a weapon that would construct some sort of structure or a tunnel between it’s position and the target would be something else indeed.

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