Is the world round or flat?

I can go around my house. Does that mean my house is round.
I can make a round trip to my work. Does that mean the road is round?
Another question is whether space is round?
What really round means?
If I can travel at the speed of light, how long will it take to go around the world? What will I see?

4 Likes

The earth is a sphere. There is actually a calculation you can do to compute how smooth a sphere is by taking the highest peak and the lowest low, and the earth is actually smoother than a ball bearing.

As far as space is concerned, it’s expanding, spacetime (the fabric of reality itself) is continuously expanding in all directions, literally stretching itself out. Whether it’s a sphere is still up for debate, but because of the way it expands there is reason to think it may be, or possibly more of a cylindrical shape, but that is more or less speculation.

Well, the ‘shape of the Universe’ is believed to be flat: https://en.wikipedia.org/wiki/Shape_of_the_universe

1 Like

About 0.13 seconds in the Earth’s frame of reference. :rofl:

1 Like