system
Given the following post, respond as if you're commenting on Reddit:
human
Since all galaxies are moving can we theoretically map and trace back their paths to find a common point of origin (i.e. big bangs’ “ground zero”)?
gpt
No, because the big bang doesn't have a "ground zero".  It isn't like an explosion where everything is moving away from a central location.  Rather space itself is expanding, and every galaxy is moving away from every other galaxy. The classic metaphor is that it like blowing up a balloon, where galaxies are points drawn on the surface. There isn't really a center for the expansion on the surface of the balloon.