Comments | hinj: How many protons does it take to fill a known universe?

hinj

How many protons does it take to fill a known universe?

Jan 07, 2012 22:18

I'm reading a number theory book (a topic I disliked greatly in college, but am trying to decide if I can deal with it now), and the author claims that the known universe would only be able to hold about 10E123 proton-sized objects. While that is indeed a large number, it doesn't seem like it is large enough. Comments ( Read more... )

math, wtf

Comments 3

sacramentalist January 8 2012, 10:49:52 UTC

What if you divide the volume of a proton into the total volume of the universe?

wow. hinj January 8 2012, 18:56:37 UTC

that's much simpler.

Uno momento.

finally! hinj January 8 2012, 20:20:48 UTC

Following Sacramentalist's suggestion (why didn't I think of that? Too long since I've taught geometry, I guess.), I came up with 9.7 x 10^142 protons let's call it 10^143), which isn't terribly diffferent from the claim made by the author, leading me to believe any difference is only due to changes in the size of the universe over the past 30 years.

Wow. That's not nearly as many protons as I thought, or 10^123 is far larger than I envisioned....

But I *loved* the exercise.