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Space Science

40 Quintillion Black Holes are Lurking in the Universe, Study Projects (livescience.com) 48

Posted by EditorDavid from the big-number-theory dept.
"Scientists have estimated the number of 'small' black holes in the universe," reports Live Science. "And no surprise: It's a lot." Using a new method, outlined January 12 in The Astrophysical Journal, a team of astrophysicists has produced a fresh estimate for the number of stellar-mass black holes — those with masses 5 to 10 times that of the sun — in the universe.

And it's astonishing: 40,000,000,000,000,000,000, or 40 quintillion, stellar-mass black holes populate the observable universe, making up approximately 1% of all normal matter, according to the new estimate.

So how did the scientists arrive at that number? By tracking the evolution of stars in our universe they estimated how often the stars — either on their own, or paired into binary systems — would transform into black holes, said first author Alex Sicilia, an astrophysicist at the International School of Advanced Studies (SISSA) in Trieste, Italy. "This is one of the first, and one of the most robust, ab initio [ground up] computation[s] of the stellar black hole mass function across cosmic history," Sicilia said in a statement....

To arrive at their estimate, the astrophysicists modeled not just the lives, but the pre-lives of the universe's stars. Using known statistics of various galaxies, such as their sizes, the elements they contain, and the sizes of the gas clouds stars would form in, the team built a model of the universe that accurately reflected the different sizes of stars that would be made, and how often they would be created.... [T]he researchers designed a model that tracked the population and size distribution of stellar-mass black holes over time to give them their eye-watering number. Then, by comparing the estimate with data taken from gravitational waves, or ripples in space-time, formed by black hole and binary star mergers, the researchers confirmed that their model was in good agreement with the data.

Astrophysicists hope to use the new estimate to investigate some perplexing questions that arise from observations of the very early universe — for instance, how the early universe became so quickly populated by supermassive black holes — often with masses millions, or even billions, of times greater than the stellar-mass holes the researchers examined in this study — so soon after the Big Bang.
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40 Quintillion Black Holes are Lurking in the Universe, Study Projects More

40 Quintillion Black Holes are Lurking in the Universe, Study Projects

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  • Matter by definition.

    • Only in the observable universe. There may be vastly more matter and black holes in the unobservable universe.

  • How much is that? A zillion?

    • How much is that? A zillion?

      One quintillion is 10^18. (That's 1 followed by eighteen zeros.)

      • With the discovery that so many stars have planets, and now so many black holes, could this account for dark matter? Seems to me it turns out there is much more normal matter than we though, so maybe the big mystery of dark matter will eventually be solved by just find more and more normal matterâ¦

        • making up approximately 1% of all normal matter No.

        • That'd be a big old nope.

          If it makes up 1% of regular for matter, then we're still a couple of orders of magnitude not enough. Specifically those black holes would make up for 0.15% of the observed gravity. We'd need around 566, give or take, times more black holes to account for it all.

          And the evidence from gravitational lensing studies do not support that conjecture.

    • It's half a Brazillian.
      And I'm making NFTs out of them. If you'd like to buy one post your Visa card below

    • Re: (Score:2)

      by MS ( 18681 )

      It depends where you are living: in US-of-A a quintillion has (5+1)*3 zeroes, while in the rest of the World a quintillion has 5*6 zeroes.

      The term quintillion stems from the latin word "quinque" = five.

  • Four thousand holes in Blackburn, Lancashire

    Humanity is living on such a tiny part of the universe that it's hard to get any sense of scale. The ten quadrillion multiplication factor from the number of potholes in a Beatles song to the number of black holes is just... very, very big.

  • For a universe whose vast majority has not been explored. The projection is as a wild guess as guessing what another person thinks.

  • Can we look for more lensing? (Score:3)

    by Invisible Now ( 525401 ) on Saturday January 22, 2022 @04:08PM (#62197667)

    Do these min black holes have strong enough gravity effects to cause light lensing effects? This might make them observable? What would this look like?
    Say for example in the deep field photo?

    • That whole "dark matter" thing - based in no small part on the assertion that we simply don't see enough matter to account for the gravitational effects we see throughout our universe. This would readily qualify as both a source of gravity and dark, so I suppose this could be called "dark matter". Is there enough to stop looking for some exotic form of matter or energy?

      I like subatomic particles that are consistent with the Standard model, thank you (don't tell me you think one exists until you figure ou

      • Yes, this is a theory that is being considered seriously [astronomy.com], though from primordial origin and in a smaller mass range than 5-10 solar mass conventional black holes as this article talks about. Perhaps something on the size of a very large asteroid to planetary mass. If they exist in large numbers they would be all over though collisions with planets would be rare. To check for this, scientists are looking toward the moons and other bodies [giantfreakinrobot.com] in our solar system for funny looking craters with an entry and exi

        • Re: (Score:2)

          by mmell ( 832646 )
          Good! I've never liked theories regarding dark matter/energy - I perceive them to be what would happen if the Cosmological Constant and Russel's Teapot had a kid together. Spooky particles in the distance, you know.

          (not dissing on Quantum theory - which, rather annoyingly, keeps making valid predictions that don't make sense even after we verify them)

      • It is right there in the summary " making up approximately 1% of all normal matter"

        For reference normal matter makes up about 5% of the universe and dark matter about 27%

  • they had to count them all.

  • This could make space travel more dangerous, no?

  • Ob FWIW: size of these "small" black holes (Score:3)

    by thatseattleguy ( 897282 ) on Saturday January 22, 2022 @04:23PM (#62197699) Homepage
    Taking the middle of the "5-10 solar masses" range at 7.5 suns, a handy online calculator tells me one of these "average" small black hole will:
    .

    - have a Schwartzchild radius (event horizon) of about 22km (= ~13.6 mi for we US Luddites)
    - ...and therefore are about 44km (27mi) in diameter from edge to edge of its event horizon
    - have a gravitational acceleration (g) at the Schwartzchild radius of ~2 trillion m/s = about 205 billion-with-a-B times Earth surface gravity

    So they're small in stellar terms, but you wouldn't want to run your Epstein-drive craft into one by mistake.

  • Nice qualifier there.

    'The universe is infinite' -or- 'The gold is in this pot.'

  • This is great news! From: http://www.sci-news.com/astron... [sci-news.com] - Spinning black holes store rotational energy that can be extracted; when a black hole is immersed in an externally supplied magnetic field, reconnection of magnetic field lines within the ergosphere can generate negative energy particles that fall into the black hole event horizon while the other accelerated particles escape stealing energy from the black hole. In a paper published in the journal Physical Review D, a duo of researchers from the U

  • More than even Carl Segan imagined!!

  • Black Hole NFTS - there's only 40 quintilion of them, so get yours today!

    When you purchase your Black Hole, you'll get a beautiful certificate with a full color picture of your personal, never-before-owned Black Hole, The certificate includes an embossed seal with your Black Hole's UNIQUE registration number. Just $99.99 today, order before midnight tonight!

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  • The number "quintillion" is meaningless (Score:3)

    by JustAnotherOldGuy ( 4145623 ) on Saturday January 22, 2022 @08:10PM (#62198129) Journal

    For most people the number "quintillion" is utterly meaningless. They've never seen it used anywhere or scaled on anything or compared to anything, and even if they did they still wouldn't understand how much a quintillion is. You might as well say there are "40 blotolian" of them. It means exactly the same thing to most people.

    You could say it's a "billion billion" (my favorite) or you could say "it's 10 ^18", or you could say "a million trillion". They may potentially be easier to understand, but most people still wouldn't have any clue as to even how big a billion is.

    The ONLY thing that "10 ^18" tells you is that whatever it is, it's bigger than "10 ^17" but smaller than 10 ^19". Whoop dee fuckin' doo.

    Those of us in technical fields sometimes work with very large or very small numbers. I've done both, and in 40 plus years over all sorts of fields I've never ever heard a colleague or anyone else use a "quintillion". Seriously, use scales that people can relate to. Just say there are "a billion billion of them".

    Summary and Recap: The number "quintillion" is meaningless

    • If scientists limited themselves to only ideas that the average layperson was already familiar with, there wouldnâ(TM)t be any science.

      âoeQuintillionâ has meaning, even if people have to Google it to find out what that meaning is.

      • If scientists limited themselves to only ideas that the average layperson was already familiar with, there wouldn't be any science

        Oh FFS, read the very first sentence in what I wrote: "For most people the number "quintillion" is utterly meaningless."

    • The ONLY thing that "10 ^18" tells you is that whatever it is, it's bigger than "10 ^17" but smaller than 10 ^19". Whoop dee fuckin' doo.

      Writing "billion billion" tells you something more than 10^18? What would that be?

      • Writing "billion billion" tells you something more than 10^18? What would that be?

        Yes, for a lot of people, writing a "billion billion" would give them a better (if still very fuzzy) idea how how "big" something is.

        They hear all the time about "billions" in terms of the economy, the number of people in the world, etc etc.

        It's a number they've heard and have some vague idea of in terms of magnitude. So a "billion billion" would probably mean more to them than a "qinitilion" or "10^18".

        We're definitely talking relative values of understanding here, but yeah, I think they'd get a better ide

  • Since the universe is supposedly infinite, how in the world can these scientists claim, with ANY accuracy, such a minuscule number for black holes? Compared to infinity, 40 quintillion IS a minuscule number. Did they *count* them?

    • Re: (Score:2)

      by bn-7bc ( 909819 )
      Well what if, instead of infinite the universe is instead boundless. Like the surface of a sphere for example, it has a finite area, but there are no delectable edges. The 4 dimenteonal universe( well space time) might be curved in a simmer way altho in a higher dimension and obviouslu on a rather enormous scale

    • Who is supposing the Universe is infinite? Not astrophysicists. All of the physics we have about it, that is supported by observation, suggests that it is finite, though very large.

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