Looking for a theorem.

Factual Questions
1

I’m trying to search for the name of a particular theorem. I’m pretty sure it’s a topological theorem. The theorem states that a unit sphere can be cut into a certain number of segments and then reassembled into a sphere of a larger size, or there abouts.

Does this ring any bells? What’s the name of this theorem?

Thanks.

2

The Banach-Tarski paradox.

3

That’s it. Thanks!

4

And, a recent thread on the topic.