• @[email protected]
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    3 days ago

    All of the rest of the physics seems to check out

    If the whole universe comes from the singularity and you need just a tiny fraction of it in a limited space to create a black hole, why the universe even exists and even more so, it’s expanding each day faster?

    • @[email protected]
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      2 days ago

      Different things.

      The singularity of a black hole is located in space.

      The initial singularity of the big bag happened “everywhere” the whole universe was supposed to have infinite density.

      The mass of the black hole is finite. It’s very dense but it have a quantifiable amount of mass.

      For the big bang the mass was also infinite as far as we know. Everything was singularity, every “energy” in your body was part of that infinitely large singularity. Not only everything but everywhere. Where you sit there was singularity during the big bang. As far as we know every single point in space was part of the initial singularity. We don’t come from a single point that exploded towards empty space. Expansion is more like the surface of a balloon. Maybe it’s better to think of it as stretching rather than expanding.

      Beyond that we don’t know much about both, there are barriers which prevent direct observation of both.

      The expansion of the universe is a completely different matter, as it’s not only expanding, it’s expanding faster that out gravitational models predict, like the universe is not only “ignoring” black holes, it’s expanding despite all observable matter, and all untraceable matter (dark matter), and it’s expanding faster and faster driven by an unknown phenomenon we call “dark energy” for giving it a name, because we have remotely not idea of what’s going on.

      • Jerkface (any/all)
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        23 hours ago

        The initial singularity of the big bag happened “everywhere” the whole universe was supposed to have infinite density.

        If the density throughout all space was truly infinite, then the volume of space had to be ZERO. Otherwise the density would have been a very very large but finite number. And if it were infinite and non-zero volume, no amount of inflation would cause it to stop being infinite. Infinity divided by any positive number is infinity.

        We know that there was a period of extreme density, but we don’t know what happened before that. When we extrapolate we EVENTUALLY come to a singularity. But that’s just a naive extrapolation, we don’t know there was a singularity. In fact, I think we can be certain there wasn’t, the way we can be certain that a coin flip never comes up head, tails and side all at the same time.

    • Skua
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      23 days ago

      The theories on why are a fair bit beyond my knowledge of physics, but I do know that they’re not necessarily the same kind of singularity. Inside a black hole (assuming our models are correct), spacetime curvature goes towards infinity. At the big bang, there may not have even been spacetime as we see it in our current universe, or whatever causes the expansion of spacetime may have been so powerful that it caused the earliest spacetime to not curve despite all the gravity