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Quick summary: We've spotted strong evidence for a supermassive black hole (of the kind that tend to sit in the center of galaxies like ours, which contains Sa

Quick summary: We've spotted strong evidence for a supermassive black hole (of the kind that tend to sit in the center of galaxies like ours, which contains Sagittarius A*) in an extremely distant galaxy - one that formed within the first half-billion or so years of the galaxy. What makes this important is that we've seen increasing evidence that supermassive black holes (SMBHs) exist earlier than we've expect if they were born from the deaths of massive stars and slowly accumulating mass in the way "typical" black holes today do. This black hole is apparently very good evidence that these early SMBHs did not form from star collapse but may have formed from gas clouds collapsing directly into black holes. Finding support for this alternative model could lead us to new possibilities in physics.

hn8305823 3y ago
> formed within the first half-billion or so years of the galaxy. Universe?
- Sai_ 3y ago
  These black holes sit in the middle of the galaxy so it’s likely they were created early in the life of the galaxy. Galaxies were still being created much after the Big Bang and the universe coming into existence.
  - digging 3y ago
    No, I meant universe. I believe the current models expect that galaxies formed around these SMBHs, not the other way around. After all, if they're collapsing directly from clouds of extremely hot gas, and they have the mass of thousands or millions of stars, it's hard to imagine there were already thousands or millions of stars in the local area not sweeping up or disturbing all that gas.
- dplavery92 3y ago
  Correct, the article places UHZ1 at 13.2 billion light-years away, so roughly ~500 Gy into our 13.7-billion-year-old universe.
  - wolverine876 3y ago
    My?
- digging 3y ago
  Yes, thank you.
Crontab 3y ago
Black hole formation without star collapse is pretty amazing. I wonder if this is something that could only happening in the early universe, when everything was closer together.
- digging 3y ago
  Yes. These primordial SMBHs can have masses comparable to entire galaxies. You most likely won't find that much matter collected densely enough anywhere in the modern universe, or ever again.
  - amatecha 3y ago
    "ever again".. until the universe collapses in upon itself? (Is that still a plausible theory as to the fate of the universe?)
    - lazide 3y ago
      Current theory is it expands forever until nothing has a chance of ever interacting with anything else.
      - SoftTalker 3y ago
        If you believe Roger Penrose, at that point spacetime ceases to exist since all matter has thinned out to nothing, all black holes have evaporated. Then, because of math I don't understand, a conformal rescaling happens and you get a new Big Bang.
        codethief 3y ago
        > Then, because of math I don't understand, a conformal rescaling happens and you get a new Big Bang. I don't think he has any math to back this up. In his theory, it just… happens.
Tazerenix 3y ago
Also important to note that the process of stellar collapse and then black hole accretion takes absolutely enormous amounts of time to collate a large amount of mass together. It's also an extremely energetic process, you would expect to see very bright black holes if millions of solar masses of matter were infalling creating very large and bright accretion disks. We do see some active galactic nuclei but not that many. There's just no way there was enough time for this to happen in the early universe, or really even after a measly 14 billion years (i.e. seeing these young supermassive black holes is challenging for the stellar collapse theory, but the theory was already pretty challenged). Not to mention if supermassive black holes were being formed by accretion, you would expect to see many intermediate mass black holes (1000-1000000 solar masses) everywhere, but we see almost none.
- JacobThreeThree 3y ago
  Agreed. The accretion theory for both star and black hole formation is not in good shape.
- dmix 3y ago
  What are some possible explanations or implications of this?
  - rishav_sharan 3y ago
    Quasi stars are one of the theories for the existense of the super massive black holes. Here is a nice video https://www.youtube.com/watch?v=aeWyp2vXxqA https://www.youtube.com/watch?v=aeWyp2vXxqA by Kurzgesagt on this topic.
  - Tazerenix 3y ago
    One of two things: Either what we know about black hole formation is basically complete (it goes gas -> star -> black hole -> accretion + collisions) but the environment in the early universe was sufficiently different/dense that parameters which rule out the formation of supermassive black holes now were different. Maybe there were many intermediate black holes just in the millions of years after the big bang and things were still close enough together that accretion could happen and collisions were "likely" at the rate needed to form SMBHs after just a billion years. If that is true we might expect to see many many active galactic nuclei as we get better telescopes and look further back, depending on how quickly such black holes formed. The other option is there is a mechanism of black hole formation that bypasses the above chain which we understand. People talk about supermassive stars, gas clouds collapsing directly into black holes, or primordial black holes that existed due to essentially random distributions of density moments after the big bang causing some regions of space to collapse into massive black holes which then persisted. Such things are far more difficult to observe, but could be inferred if we don't see many many active nuclei as we get better telescopes but all other indications of the accuracy of the big bang + inflationary theory hold true.
fsckboy 3y ago
> This black hole is apparently very good evidence that these early SMBHs did not form from star collapse but may have formed from gas clouds collapsing directly into black holes. I'm no expert, but wouldn't it make sense that in a non-uniform expanding explosion, the densely packed areas would behave the way density behaves? If the universe expands over time, isn't it denser near the beginning, allowing large scale density events to take place early in time? Couldn't a dense universe have allowed supermassive stars to form that just immediately collapsed? It's cool to discover it or anything else, but I'm not clear on why we should be surprised?
- falserum 3y ago
  No expert either, but what you suggest is hypothesis. Article reports some new evidence that seem to support it. Not every seemingly obvious hypothesis is true. My personal favourite at-first-counterintuitive law of nature: in orbital mechanics, to catch-up, speeding-up does not work. Speeding up (1) changes the orbit, (2) elevates the orbit, (3) higher orbit has lower speed. (Excluding trivially close distances)
  - dmix 3y ago
    So how do you catch up then?
    - abcrawf 3y ago
      Slow down and take the shortcut.
    - bashinator 3y ago
      Slow down to get into a lower orbit, where you will overtake your target. Then speed up to get back into the higher orbit where the target will catch up with you.

hn8305823 3y ago

> formed within the first half-billion or so years of the galaxy. Universe?

Sai_ 3y ago
These black holes sit in the middle of the galaxy so it’s likely they were created early in the life of the galaxy. Galaxies were still being created much after the Big Bang and the universe coming into existence.
- digging 3y ago
  No, I meant universe. I believe the current models expect that galaxies formed around these SMBHs, not the other way around. After all, if they're collapsing directly from clouds of extremely hot gas, and they have the mass of thousands or millions of stars, it's hard to imagine there were already thousands or millions of stars in the local area not sweeping up or disturbing all that gas.
dplavery92 3y ago
Correct, the article places UHZ1 at 13.2 billion light-years away, so roughly ~500 Gy into our 13.7-billion-year-old universe.
- wolverine876 3y ago
  My?
digging 3y ago
Yes, thank you.

Crontab 3y ago

Black hole formation without star collapse is pretty amazing. I wonder if this is something that could only happening in the early universe, when everything was closer together.

digging 3y ago
Yes. These primordial SMBHs can have masses comparable to entire galaxies. You most likely won't find that much matter collected densely enough anywhere in the modern universe, or ever again.
- amatecha 3y ago
  "ever again".. until the universe collapses in upon itself? (Is that still a plausible theory as to the fate of the universe?)
  - lazide 3y ago
    Current theory is it expands forever until nothing has a chance of ever interacting with anything else.
    - SoftTalker 3y ago
      If you believe Roger Penrose, at that point spacetime ceases to exist since all matter has thinned out to nothing, all black holes have evaporated. Then, because of math I don't understand, a conformal rescaling happens and you get a new Big Bang.
      - codethief 3y ago
        > Then, because of math I don't understand, a conformal rescaling happens and you get a new Big Bang. I don't think he has any math to back this up. In his theory, it just… happens.

Tazerenix 3y ago

Also important to note that the process of stellar collapse and then black hole accretion takes absolutely enormous amounts of time to collate a large amount of mass together. It's also an extremely energetic process, you would expect to see very bright black holes if millions of solar masses of matter were infalling creating very large and bright accretion disks. We do see some active galactic nuclei but not that many. There's just no way there was enough time for this to happen in the early universe, or really even after a measly 14 billion years (i.e. seeing these young supermassive black holes is challenging for the stellar collapse theory, but the theory was already pretty challenged). Not to mention if supermassive black holes were being formed by accretion, you would expect to see many intermediate mass black holes (1000-1000000 solar masses) everywhere, but we see almost none.

JacobThreeThree 3y ago
Agreed. The accretion theory for both star and black hole formation is not in good shape.
dmix 3y ago
What are some possible explanations or implications of this?
- rishav_sharan 3y ago
  Quasi stars are one of the theories for the existense of the super massive black holes. Here is a nice video https://www.youtube.com/watch?v=aeWyp2vXxqA https://www.youtube.com/watch?v=aeWyp2vXxqA by Kurzgesagt on this topic.
- Tazerenix 3y ago
  One of two things: Either what we know about black hole formation is basically complete (it goes gas -> star -> black hole -> accretion + collisions) but the environment in the early universe was sufficiently different/dense that parameters which rule out the formation of supermassive black holes now were different. Maybe there were many intermediate black holes just in the millions of years after the big bang and things were still close enough together that accretion could happen and collisions were "likely" at the rate needed to form SMBHs after just a billion years. If that is true we might expect to see many many active galactic nuclei as we get better telescopes and look further back, depending on how quickly such black holes formed. The other option is there is a mechanism of black hole formation that bypasses the above chain which we understand. People talk about supermassive stars, gas clouds collapsing directly into black holes, or primordial black holes that existed due to essentially random distributions of density moments after the big bang causing some regions of space to collapse into massive black holes which then persisted. Such things are far more difficult to observe, but could be inferred if we don't see many many active nuclei as we get better telescopes but all other indications of the accuracy of the big bang + inflationary theory hold true.

fsckboy 3y ago

> This black hole is apparently very good evidence that these early SMBHs did not form from star collapse but may have formed from gas clouds collapsing directly into black holes. I'm no expert, but wouldn't it make sense that in a non-uniform expanding explosion, the densely packed areas would behave the way density behaves? If the universe expands over time, isn't it denser near the beginning, allowing large scale density events to take place early in time? Couldn't a dense universe have allowed supermassive stars to form that just immediately collapsed? It's cool to discover it or anything else, but I'm not clear on why we should be surprised?

falserum 3y ago
No expert either, but what you suggest is hypothesis. Article reports some new evidence that seem to support it. Not every seemingly obvious hypothesis is true. My personal favourite at-first-counterintuitive law of nature: in orbital mechanics, to catch-up, speeding-up does not work. Speeding up (1) changes the orbit, (2) elevates the orbit, (3) higher orbit has lower speed. (Excluding trivially close distances)
- dmix 3y ago
  So how do you catch up then?
  - abcrawf 3y ago
    Slow down and take the shortcut.
  - bashinator 3y ago
    Slow down to get into a lower orbit, where you will overtake your target. Then speed up to get back into the higher orbit where the target will catch up with you.