Our flat universe

Not a curve in sight, as far as the eye can see. Mathematicians, scientists, philosophers and curious minds alike have guessed at the shape of our universe. There are three main options to choose from, in case you’d like to do some digging of your own: The universe could be positively curved, like a sphere. The universe could be negatively curved, like a saddle. The universe could be flat, like a sheet of paper. As far as scientists can tell, this third option is correct. But what do people re...