Gravitational force is never truly zero. If it has mass, it is pulling at you, though it may be so close to zero that you don’t realize it.

  • radix@lemmy.worldEnglish
    40·
    9 months ago

    Any given star is constantly emitting an unimaginably large, but finite, number of photons. A tiny few of them travel tens to hundreds of (Earth) years, only to end their journey in your eyeballs.

    • NOT_RICK@lemmy.worldEnglish
      17·
      9 months ago

      Even crazier when you consider how long that photon bounced around inside the star before escaping out into space

      • LostXOR@fedia.io
        15·
        9 months ago

        Technically the photon is being absorbed and re-emitted inside the star, so it’s not exactly the same photon.

        • intensely_human@lemm.ee
          63·
          9 months ago

          A “photon” is basically just the universe producing a new field in response to an existing one, repeatedly. So photons travel through space in much the same way: they are absorbed and emitted by successive regions of space, with each region being the photon’s wavelength in size.

            • intensely_human@lemm.ee
              2·
              9 months ago

              Can you describe exactly how it is wrong, or is it just a feeling? Are you not familiar with the structure of an electromagnetic wave?

              • Feathercrown@lemmy.worldEnglish
                2·
                9 months ago

                I’m familiar with the structure, but don’t the electrical and magnetic waves smoothly translate across space? They aren’t “absorbed and emitted by successive regions of space”, right?

                • intensely_human@lemm.ee
                  2·
                  9 months ago

                  If you graph the electric field strength along a photon’s flight path, there are points where it is zero. Same for the magnetic field strength.

                  The energy of the photon is transformed continuously between electric and magnetic field potential, and if you consider either of those signals the energy is coming into and going out of that medium repeatedly.

                  Because each of those non-zero periods of field potential happens in a particular spot in space (those fields don’t move; they grow and fade in sequence), I’m saying that region of space has absorbed the photon.

                  Of course, you know, particle wave duality. So in some ways they travel smoothly as well.