Imagine a Universe where you could guide a spaceship in one direction and eventually return to where you started. If our Universe were a finite doughnut, such movements would be feasible, and physicists might calculate its size. But, instead, Buchert and a team of astrophysicists have inferred that our Universe may be doubly connected, meaning that space is closed in on itself in all three dimensions like a three-dimensional doughnut, based on light from the very early past.
Such a Universe would be finite, and their findings suggest that our entire cosmos is only three to four times larger than the observable limits, which are around 45 billion light-years away. Physicists explain the Universe using Einstein’s general relativity vocabulary. That language ties space time’s contents to its bending and warping, which then teaches those contents how to interact. For example, the force of gravity is felt in this way.
The geometry determines its fate. A closed world would eventually collapse in itself, whereas a flat and open would continue to grow indefinitely. Multiple studies, particularly from the cosmic microwave background, have proven that we live in a flat Universe Our will continue to expand as parallel lines remain parallel. But shape is more than just geometry. Topology refers to how figures can vary while adhering to the same geometric laws.