• Nougat@fedia.io
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    1 month ago

    Don’t forget the inverse square law. Even without a change in medium or any obstacles, the strength of the signal decrease over distance until it is undetectable.

    This is also why there are no extraterrestrial civilizations hearing any radio broadcasts from Earth. Our transmitters are so weak that any signals we send out fade into the CMB before they get any real distance.

    • Clent@lemmy.world
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      1 month ago

      You area conflating auditory waves with radio waves.

      These are very much not the same thing. Sound waves require a medium while radio waves do not.

      Radio waves travel vast distances through space while sound doesn’t travel at all.

      • Nougat@fedia.io
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        1 month ago

        Space is a medium, as exemplified by the fact that light curves around massive objects, because the space is curved.

        • huginn@feddit.it
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          1 month ago

          Space isn’t a medium because mediums have privileged frames of reference.

          You’re talking about spacetime which is a field, not a medium.

            • huginn@feddit.it
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              1 month ago

              Light is also not “stuff” - it’s electromagnetic radiation. It’s by the unprivileged intertial frame of reference that we define the speed of light. Light’s speed is the speed at which it travels unimpeded through the spacetime “field”. Additionally light does not accelerate or change speed in any way while traveling in that frame.

              Unless you’re asking if light travels through things that are not the field known as the spacetime continuum in which case yes: light travels (and changes speed) through all sorts of materials. Like glass.

        • xthexder@l.sw0.com
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          1 month ago

          They’ve probably just got a spy satellite around earth that transmits back. Or maybe an extremely directional antenna / receiver dish would work, since they’re focused on Earth specifically.

      • Nougat@fedia.io
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        1 month ago

        They would not have been able to watch it from an original OTA broadcast, no.

    • Rhaedas@fedia.io
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      1 month ago

      If they didn’t fade with distance, this is as far as they have gotten. So for now we are still quiet in the dark forest.

    • Semi-Hemi-Lemmygod@lemmy.world
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      1 month ago

      If we had FTL I’d be a radio archaeologist, flying out to various distances to attempt to capture lost episodes of old TV shows like Doctor Who