A pointless calculation

I'm an expert in pointless calculations - I perform millions of them everyday, usually because I've screwed up a parameter file. I made one by hand today though, and it was catalysed by Jim1. He walked into OC320 and declared:

"John and I have decided that the Universe is really big."

Of course, they're right - although PPARC might argue that this doesn't constitute original research. Anyway, since z=10 is about the furthest we can see, we wondered just how far away that is, in real terms. Geachy's cosmology calculator puts z=10 at about 1.6 Gpc in the fashionable cosmology. We worked out it'd take ~10^18 yrs to lazily walk that far, without accounting for toilet breaks. That certainly is a long time, especially when you consider that in that time the Universe itself could have evolved from the Big Bang to its present state 120 million times over.

So, in conclusion, the Universe *is* really, really, really bloody big. And yet amazingly four of us still have to cram into this office...