The Curvature of the Universe

By Fraser Cain - September 10, 2013 at 1:47 AM UTC | Cosmology

A while back we introduced you to Zogg the alien from Betelgeuse. Zogg has been busy helping aliens understand bizarre human concepts like "rituals" and "vision", but he took a side journey to help everyone understand the geometry of the Universe. What does it mean to have a flat, finite Universe? How could you travel in one direction and return to your starting point?

The first episode was fantastic, and now serves as my favorite link to send people when they're having trouble wrapping their head around the concept of a finite Universe. How the Universe can be expanding, without expanding into anything. Seriously, if you haven't seen

Part 1, stop and go watch it now

.

True to his word, Zogg released this second episode, detailing the geometries of the Universe. What do cosmologists mean when they say the Universe is "curved" or "flat". What could the curvature look like.

Watch it and enjoy. I can't wait for Part 3.

Fraser Cain

Fraser Cain

Fraser Cain is the publisher of Universe Today, founding the website in March 1999. He's also the co-host of Astronomy Cast.