Are “matter” and “space” opposites?
Not in reality. They are idealizations. Matter was once thought to be solid, without space. Space was once thought to be empty, without matter. The reality, we have learned, is that all matter contains space (e.g., the atom); all space contains matter (e.g., no absolute vacuum is possible). Reality is always something in between solid matter and empty space. Our idea of nothingness is just that, an idea. No part of the infinite universe could be devoid of matter: nonexistence is impossible.
