Comments | donrumata: (без темы)

donrumata

(Untitled)

Mar 19, 2004 03:40

Today in the shower I thought that, maybe, if the the universe expanded uniformly it'd be about 4.307 times 10 to the 70th power cubic kilometers big or so. Well, that is, I calculated the number with my calculator when I got out. But I did think the universe is pretty mindimplodingly huge.

Comments 11

rxrfrx March 19 2004, 04:57:08 UTC

more like 10^78... but if i remember correctly from a few months ago when i "learned" this stuff, it isn't currently thought that the universe has expanded at the speed of light for its entire existence.

donrumata March 19 2004, 06:27:19 UTC

Well, I don't think it's thought the universe ever expanded at the speed of light, save maybe an instant as it slowed down to its current pace and began to accelerate again. Either way, I figured it was expanding as space rather than as matter, so that doesn't count. But I based it on simply converting time units to space units rather than on it expanding at the speed of light.

donrumata March 19 2004, 07:00:24 UTC

I mean I figured, it covered a particular amount of time, regardless of its pace, and the speed of light is the speed of light.

rxrfrx March 19 2004, 08:03:08 UTC

oh, ok. then maybe our numbers were just coincidental. actually, now that i think about it, i'm probably wrong too, as the univers isn't supposed to be spherical anyway... more of a flat disk or something... i think.

one generally estimates the size of the universe and the age of the universe by measuring one somehow and then finding the other. but the thing i learned this semester is that methods of doing this rely on a lot of assumptions that often turn out to be wrong.

Thread 9

notestaff March 19 2004, 05:46:55 UTC

...but just think how much bigger it was before the invention of modern mathematical notation. Just try writing this out in Roman numerals: MMMMM..... Or in unary notation: 11111.... The description might not fit in the Universe. Apparently, the Universe has shrunk quite a bit in the last few thousand years.

mattraibert March 20 2004, 00:07:35 UTC

There are much more data efficient ways of representing numbers than "mathematical notation". Humans just aren't particularly good at interpreting them.