The notion of infinity is fundamentally beyond the human ability to comprehend, but that hasn’t stopped mathematicians from trying. So just what is infinity, and why is there more than one of them?

What can baby carrots tell us about infinity? Photo by ilovebutter/flickr/CC BY 2.0 Infinity is big. Really big. As mathematician Eugenia Cheng puts it, it’s the “biggest thing there is.” In her new ...