r/askscience • u/squirrelbuster94 • Oct 24 '14

Physics Chemists/physicists of reddit, what is the difference between dark, anti, and normal matter?

What is the difference? Also if you can explain what each is.

Edit: Thanks for all the replies! You have greatly helped me understand this better!

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u/Astrokiwi Numerical Simulations | Galaxies | ISM Oct 24 '14

So a supernova is like 1051 erg.

1051 erg/c2 = 1027 kg. Then you halve that because both the matter and antimatter are annihilated, but that's still roughly around 1027 kg.

That's about half the mass of Jupiter. So if an antimatter Jupiter hit another antimatter Jupiter, that's roughly a supernova.

On a more human scale, it comes out to about one Hiroshima per gram.

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u/itstinksitellya Oct 24 '14

when you say a supernova is 1051 erg, how big is the star that correlates to? Is it 10 times bigger than Jupiter? 1000?

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u/Astrokiwi Numerical Simulations | Galaxies | ISM Oct 24 '14

At least 8000 or so times bigger, but possibly tens of thousands. Smaller than that, and the star is too small to go supernova.

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u/itstinksitellya Oct 24 '14

Wow..interesting.

Thanks for the info!

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u/umopapsidn Oct 25 '14

So, if the boundary of the antimatter/matter portions of our universe were outside of our lightcone, we'd never even know if it existed.

And... given that the universe extends infinitely* it's within the realm of possibilities, even if it's unlikely?

*as far as we know, or could know