I’ve been reading The Infinite Book: A Short Guide to the Boundless, Timeless and Endless, which so far is a history of theories on infinity. Infinity is something that I’ve always been interested in, but I had never read theories predating Hawking. I came across an article on the web today called A Brain Cell is the Same as the Universe. I’m afraid a brain cell is not like the universe. The universe is another name for infinite space and time. The web site claims that the universe is billions of light years across, which doesn’t make sense to me. Since when is the universe a finite structure? I just don’t see the comparison.