Why is there a normal galaxy sitting at the edge of the Universe?

Re:Why is there a normal galaxy sitting at the edge of the U... by jquery on Wednesday September 09, 2020 @04:42PM (#24425695)

> Carlo Rovelli and others propose that black holes actually only appear as they do to us due to the extreme time dilation, and similar to how a photon's "perspective" is that it's experiencing all of time at once, a black hole's perspective is that it's basically a massive explosion that occurs at essentially the same moment it forms. So under this hypothesis, a black hole never reaches a true singularity, but as close to a singularity as physically possible, and then it almost instantaneously bounces back like a taut rubber band that's stretched back as far as it'll go. From our perspective on the outside, it's an intense explosion occurring in very slow motion, and from the perspective on the inside, it's an intense explosion happening all at once.

I’ve been yelling like a crank for a while that a black hole is actually a massive explosion we see in (ultra) slow motion, so it’s really cool to hear I’m not alone, and that other people call it a “planck star”. I haven’t heard anyone connect that to the big bang being a white hole, but it does make a lot of sense, even if we currently have no direct observable evidence or even any theoretical predictions.

Thanks for sharing, now I can follow along the research.

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Re:Why is there a normal galaxy sitting at the edge of the U... by meowface on Wednesday September 09, 2020 @06:02PM (#24426445)

Don't know why you're being downvoted. It's definitely not too crazy of an idea, given what's been known since general relativity was confirmed and the discovery that black holes do indeed exist. I haven't looked into it, but I wouldn't be surprised if many other people have proposed it in the past. I haven't heard or thought of it before, but when I first read it it definitely made a lot of sense, intuitively.

Maybe the downvotes (which seem to no longer outweigh the upvotes?) are because you said "is actually" rather than "might actually be". Humility and uncertainty is crucial in science. Even for a field that's much more testable, and even for a leading scientist in a field, let alone some random speculator on the internet. It's fun to think and talk about these things, but especially as total amateurs, we should never claim anything with even a little bit of confidence.

My own speculative stuff I posted above is probably all dead wrong and hopelessly confused; I'm just throwing it out there as stuff that's popped into my head. And Rovelli may be wrong, too, though he's a highly-respected theoretical physicist and has published several papers about it. And even if the Planck star and black hole/white hole theory is true, it may not necessarily mean it has anything to do with how our universe started; that's just additional unsubstantiated speculation by me and some other people, and not anything Rovelli has claimed, though his theory seems to have increased discussion about that topic.

Here're some resources:

https://phys.org/news/2014-02-astrophysicists-duo-planck-sta...

https://en.wikipedia.org/wiki/Planck_star

https://en.wikipedia.org/wiki/White_hole#Big_Bang/Supermassi...

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Re:Why is there a normal galaxy sitting at the edge of the U... by jquery on Wednesday September 09, 2020 @09:34PM (#24428005)

You’re dead-on about humility. I meant it was nothing more than my idle speculation based on my shallow understanding of physics. I was just so excited to see there’s an entire theory around it! Thanks for sharing more resources. Cosmology continues to fascinate me.

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