undefined | Better HN

0 pointsrubicon337y ago0 comments

> Kip’s description of black holes here is also fascinating: https://youtu.be/oj1AfkPQa6M — first time I learnt what “warped” space-time means :)

In this video he makes a comment which I struggle to fully understand:

He says that ALL of the matter which belonged to the cooled-off star is DESTROYED in the process of creating a black hole.

That concept of complete destruction eludes me. I assume what he means is, the matter was converted entirely to energy. Right?

But if that's true - where is all of that energy? Is it stored (somehow?) in the Black Hole? Is it dispersed throughout the galaxy? What HAPPENED to the mass (energy)?

0 comments

1 comments · 1 top-level

roywiggins7y ago

It's all squished into the black hole and from the perspective of everyone outside, converted into... more mass of the black hole. The mass of the black hole comes from the mass that created it. As you feed it more stuff, it gets more massive.

As to what physically happens to the stuff once it's inside, I don't know if we know for certain. It gets dragged towards the center. From the point of view of the rest of the universe, it might never actually reach the singularity: GR would make it look like it's going slower and slower and slower.

Speculation about what is actually inside the event horizon is at most mathematical extrapolation, since we can't actually crack one open and look.

j / k navigate · click thread line to collapse