• Sterile_Technique@lemmy.world
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    1 year ago

    Doesn’t that not mesh with the whole “space is constantly expanding” thing?

    If the observable universe was all in a black hole, everything would be moving closer together as we get pulled toward the singularity.

    …right? Definitely not my area of expertise, but the little I do know is raising a few flags.

    • notfromhere@lemmy.one
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      1 year ago

      Things nearest the center would move towards the center at an accelerated rate. So observation from the perspective of an object falling in the black hole could be everything is expanding? Since everything is getting compressed as it goes toward the center. I’m not an expert on anything but it seems like an intriguing concept.

      • MüThyme@lemmy.world
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        1 year ago

        It won’t work like that, the expansion we observe has no directional bias. If it were due to some collapse to a well defined point, we’d be able to tell the difference.

    • fsxylo@sh.itjust.works
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      1 year ago

      Iflscience is a pop science website. There’s no guarantee this isn’t bullshit.

    • Spzi@lemm.ee
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      1 year ago

      From the article:

      we learn that the entire observable universe – the area that sits within the “Hubble radius” is also on that line. In other words, if a black hole was as large as the universe we can see, it would have the same density as the universe.

      Not saying any of this makes sense, but you seem to be working with different assumptions.

      Another narrative could be: As mass gets added to the black hole, it (the universe) grows.

      • MüThyme@lemmy.world
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        1 year ago

        That also isn’t how it works, I’m afraid.

        The black hole gets less dense because the so called “event horizon” becomes larger, the space inside doesn’t stretch like we see in the universe.

        It’s a little removed from my area, but as I understand it there are similarities in the maths. The observable universe has a horizon in some sense, but it’s not a point if no return like a black hole, so much as a point of “the universe hasn’t existed long enough for anything to be able to travel that far yet”

        This has a similar effect as a black hole, but it’s really just a concept we see in perfectly flat empty space, light taking time to move.

          • MüThyme@lemmy.world
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            1 year ago

            Oh yeah, that’s also a great point, the Hubble horizon!

            It turns out there are a few different horizons in cosmology like that, they really do show up everywhere.