Ask Ethan: What does the edge of the Universe look like?
“If the universe is finite in volume, then is there a boundary? Is it approachable? And what might the view in that direction be?”
When we look at the nearby Universe, it looks a lot like we, ourselves, appear. Nearby galaxies are similar in structure to our own; the stars inside them have the same properties, masses, ages and distributions as our own. But as we look to greater and greater cosmic distances, we find that more distant galaxies appear younger, bluer, smaller, and less evolved. If we go back beyond a certain point, there are no more galaxies at all. What’s going on? Does this mean that, if we go back far enough, there’s an edge to the Universe? And if so, what does that mean? What lies beyond it? And what would someone living on that edge see and perceive? It turns out that there is a boundary to our Universe, but not in space.