Through the Wormhole: Is There an Edge to the Universe?It is commonly theorized that the universe began with the Big Bang 13.7 billion years ago. But since we can only see as far as light has traveled in that time, we can't actually make out the edge of the universe. Could it be that the universe is infinite? Is there any way to find out what the shape of the universe really is? Can we find the edge, discover what might lie beyond it, and perhaps even discover a universe next to ours?

Except for mathematicians and physicists, most people don't like infinity. We like to know the extent of things. We can wrap our heads around measurements. Your car might be 10 feet long, your house is 2,000 square feet, the U.S. national debt is … well, some things are more finite than others.

But what about our universe? It's definitely big. Just how big and what shape it is consumes much of the debate in the world of cosmology. Calling it our universe is important, because today's most commonly accepted theory on the cosmos, string theory, says ours is but one space-time bubble among an infinite host of other parallel and bubbly universes. They cleverly call this a multiverse, and it's way more complex than most people would ever want to know. List of all episodes here: Through The Wormhole.

Watch the full documentary now. Available only in United States.