Infinity is Not So Big

I intended to write about Linux today. That is, I had intended that, today, I would write about Linux. Nothing to do with That was because I have ordered Debian from the Linux Emporium. But it hasn’t arrived yet (hopefully it’s sitting at home waiting for me), and I was just now struck by an alternative topic: Infinity. More on Linux when it arrives.

This being my third day back at college after the Christmas break, and my first day of Nuclear Physics (Exph3012), we were given somewhat of a broad introduction to the area (obviously not too elementary, having covered the subject in first year). During a discussion of radioactivity and particle lifetimes, the lecturer referred to the life-time of a proton. Now protons are very stable particles. No-one should be surprised by this, there’s no reason to think otherwise. So we[1]‘re used to the idea that a free proton, ignoring outside influence, will last forever. Forever doesn’t seem too long. Now I’m suddenly given a number for its minimum life-time[2], and it’s huge. “Not less than 1039 years.” That’s 100,000,000,000,000,000,000,000,000,000 times the age of the Universe. One hundred thousand trillion trillion times. It’s quite an unimaginable time-frame, while “forever” seems quite reasonable. It’s as if the mind (mine, at least; YMMV) tries valiantly to stretch around this vast number, fails, and finally collapses in a confused heap (similar to the state in which it began), while it will happily ignore any mention of “forever”, possibly with the assumption that it misheard.

[1] That is, physicists and other interested parties (nerds). My mother, for example, would be quite unfamiliar with this idea.

[2] We know that the life-time isn’t less than this time. It could well be more. It could, indeed, be infinite.