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2 votes
0 answers
234 views

How to derive number of nucleons in Universe?

I understand that there are roughly $N=10^{79}$ nucleons in the visible Universe. This number comes from adding up the nucleons of $100$ billion stars in $100$ billion galaxies in the visible Universe ...
John Eastmond's user avatar
4 votes
2 answers
1k views

What paper can I cite for the estimated number of atoms in the observable universe to be lower than $10^{82}$?

The title contains the whole question. I am a logician in theoretical computer science and want to use the estimated number of atoms in the observable universe to show what a ridiculous amount of ...
47 votes
2 answers
41k views

Dumbed-down explanation how scientists know the number of atoms in the universe?

It is often quoted that the number of atoms in the universe is 10$^{70}$ or 10$^{80}$. How do scientists determine this number? And how accurate is it (how strong is the supporting evidences for it)...
Pacerier's user avatar
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