Title text:

Unstoppable force-carrying particles can’t interact with immovable matter by definition.

Transcript:

[An arrow pointing to the right and a trapezoid are labeled as ‘Unstoppable Force’ and ‘Immovable Object’ respectively.]
[The arrow is shown as entering the trapezoid from the left and the part of it in said trapezoid is coloured gray.]
[The arrow is shown as leaving the trapezoid to the right and is coloured black.]
[Caption below the panel:] I don’t see why people find this scenario to be tricky.

Source: https://xkcd.com/3084/

explainxkcd for #3084

  • Cocodapuf@lemmy.worldEnglish
    2·
    23 hours ago

    You need to be thinking about n-body physics though, everything affects everything. If the earth moves, that moves the sun a little, if the sun moves, that moves the local cluster a little, etc. Why wouldn’t that affect this heaviest object?

    I mean, are you suggesting that this heaviest object is simply the center of the universe and that all coordinates are defined around it? Because while that seems practical, I don’t think it’s how matter and space interact.

    • Saleh@feddit.orgEnglish
      21·
      23 hours ago

      The universe is expanding everywhere all at once in all directions. So space itself is “moving”. It is impossible to define movement except relative to another object made from matter.

      • Cocodapuf@lemmy.worldEnglish
        3·
        22 hours ago

        Ok, I think we’re on the same page here. But I’m still not sure about one of your previous comments, you suggested that this “heaviest object” can’t move because it would be the logical reference to which any other body is measured.

        But I want to think about that a bit. Let’s say this heaviest object (HO) has something orbiting it and we’re looking at it from earth with a telescope. As the smaller body orbits, we would probably see this HO wobble, right? Meaning that even if it’s the most massive thing around, it’s still affected by other objects, it can be moved.