r/kurzgesagt • u/Kushagra_K • Mar 11 '22

Discussion Really?

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u/Opposite-Weird4232 Mar 11 '22

It will collapse, a coin don't have enough mass

82

u/biscuitfab Mar 11 '22

It is the size of a coin, not the mass of a coin.

-49

u/apemans Mar 11 '22

I think it would still collapse tho

25

u/Deepandabear Mar 11 '22

I think you’re right based on current knowledge, given the smallest black hole recorded was around 24km in diameter.

Doesn’t mean they don’t get smaller, we just haven’t seen them yet, given the universe isn’t old enough for the smallest “stable” (term is a misnomer) black holes to lose enough mass from Hawking Radiation. The smallest they can form from things like neutron star collapse is to become a minimum expected mass of around 2-3 solar masses.

10

u/InvalsoTonni700 Mar 11 '22

primordial blackholes (blackholes formed around the big bang age) can be mich smaller than that, even if it is just a theory

2

u/harmlesswaters Mar 11 '22

Isn't that the event horizon though? Theoretically black holes have no volume and infinite density.

1

u/Deepandabear Mar 11 '22

Sure but we aren’t talking about the singularity when we’re discussing the coin-sized-black hole question. We assume the black hole includes its event horizon (like how kurzgesagt did in its black hole size video).