Ok getting some real sciency answers which proves you are way better than I am. Can you guys and gals break some of it down like I am 5 or so?

  • ryrybang@lemmy.worldEnglish
    4·
    2 days ago

    Speed of light is a constant. For everyone. Because it’s linked to time, which is part of 3D space.

    Let’s say you are standing still. Shoot a laser straight out in front of you. Measure the speed, you get c, the speed of light.

    Now, start running forward at 10 mph. Shoot the laser again. Measure the speed. You still get c. Not c + 10, but exactly c.

    Run backwards shoot laser out in front of you. Still exactly c.

    Because your personal time/clock has changed by moving so that you end up measuring the speed of light the same.

    Anyone looking at you, regardless of their relative motion to you will also measure your laser at c.

    It’s just how the universe is.

    Also, speed of light isn’t really the best term. More like maximum speed of the universe. Light just happens to travel at that speed because it has no mass. Everything with no mass travels at that speed.

    • yoevli@lemmy.worldEnglish
      1·
      2 days ago

      I just want to add that apart from time dilation, velocity also causes length contraction wherein an object will be measured as shorter when it’s moving relative to the observer versus from its own rest frame. I’ve always found it (and time dilation) to be very unintuitive to reason about with my monkey brain - relativity in general is just super weird.