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Possible detection of a black hole with a mass that was thought to be impossible
- brianberns 7y agoThe title is misleading. Just to be clear, theory predicts that blacks holes shouldn't be created between 50 and 130 solar masses, but there are plenty of black holes >130 solar masses. This is just an observation of a black hole that falls inside the supposedly "forbidden" range.
- jacobush 7y agoI agree except the word "just". It's really interesting that it exists contrary to current theories.
- NikolaeVarius 7y agoThe article discusses that there are multiple theories explaining the possibility of alternative modes of formation.
- joemag 7y agoMisleading indeed. And I’m surprised the article did not talk about binary black hole mergers being potential sources of such black holes, since that seems like the most plausible theory.
- ars 7y agoDid you read the whole article? It did talk about that. It gave a whole explanation.
- eesmith 7y agoI thought it did talk about binary black hole merges as one source. Here's a quote from the article which seems to match what you describe: > Inside a globular cluster, a 50-solar-mass black hole could merge with a 30-solar-mass one, for instance, and then the resulting giant could merge again. This second-generation merger is what LIGO/Virgo might have detected
- joemag 7y agoArgh, you are right - the ad fold made it seem like the article ended, yet there were two more paragraphs below it. Still, rereading the article, the main body seemed a bit coy. It kept talking about how such black holes should not exist, yet I kept thinking “hasn't LIGO detected formation of 60+ solar mass black holes via mergers?” But perhaps I’m in an extra criticizing mood before my morning coffee.
- samstave 7y agoOk, so now i realize that i have absolutely no idea what a black even actually is. Can HN ELI5 what a black hole actually is and explain how they even come into existence, let alone that binaries can combine??
- chousuke 7y agoI'm not an astrophysicist but I think I can provide a reasonably accurate answer anyway. Basically, you get a black hole when you push matter together tight enough. This happens when some stars die, and the processes inside the star can't counteract its own gravity. Light is affected by gravity. A black hole is an object whose gravitational "pull" is so powerful that inside a certain radius, everything gets inevitably pulled into it. This causes the event horizon, where even light can't get away. What's inside the event horizon is not known, as far as I know, except that it has mass, charge and angular momentum Black holes colliding is essentially no different from any other two objects colliding in space, except for the cataclysmic scale. They behave pretty much like any other object of their mass would, which means you can have two black holes orbiting each other in a binary system just like two stars would.
- samstave 7y agoI really loved this ELI5, thank you.
- chousuke 7y agoI guess it was more of an ELI5 for kids with exceptional vocabulary. :P One thing I neglected to mention is that the effect of gravity gets weaker with distance, so conversely it must get stronger the closer matter is pressed together. And as it gets stronger, the object gets denser because (in the absence of counteracting forces) its matter is further pulled together, and it becomes a loop until you get a black hole. Beyond that things get weird and we don't know what exactly is going on, but we do know that it happens.
- samstave 7y ago
- SkyBelow 7y agoIs there an ELICU (college undergrad) as to why 50 to 130 is forbidden but below and above is allowed?
- saagarjha 7y agoHow’s the one the article mentions? > A pair-instability supernova happens when the core grows so hot that light begins to spontaneously convert into electron-positron pairs. The light’s radiation pressure had kept the star’s core intact; when the light transforms into matter, the resulting pressure drop causes the core to rapidly shrink and become even hotter, further accelerating pair production and causing a runaway effect. Eventually the core gets so hot that oxygen ignites. This fully reverses the core’s implosion, so that it explodes instead. For cores with a mass between about 65 and 130 times that of our sun (according to current estimates), the star is completely obliterated. Cores between about 50 and 65 solar masses pulsate, shedding mass in a series of explosions until they drop below the range where pair instability occurs. Thus there should be no black holes with masses in the 50-to-130-solar-mass range.
- changoplatanero 7y agoWhat if two blackholes with 50 solar masses collide into each other?
- lostmsu 7y agoAFAIK, nothing prevents that. You'd want blackholes with 100 solar masses though, as the collision will apparently shed significant part of the mass in gravitational waves.
- TCR19 7y agoSo does that mean during a collision between blackholes mass actually does/can escape a blackhole? I thought mass couldn't escape, at least not in any observable way that we can detect. [I don't know a ton about astrophysics, so apologies if this question doesn't make sense].
- saiya-jin 7y agoCouldn't it evaporate into this size, or consume enough stars / other material to grow so large? Universe is young, but not so young this should be impossible
- semi-extrinsic 7y agoWrt. evaporation: no. Here is a handy online black hole calculator http://xaonon.dyndns.org/hawking/ http://xaonon.dyndns.org/hawking/ Punch in 130 solar masses, and you get a lifetime (before evaporation) of around 10^72 years. Age of the universe is 10^10 years, so evaporation is utterly negligible.
- tgb 7y agoThis was my first question, too. Disappointing that HN downvotes good-faith, on-topic questions.
- asdfman123 7y ago> This is just an observation of a black hole that falls inside the supposedly "forbidden" range. So you're saying it's of a mass that was thought to be impossible?
- endorphone 7y agoIf there were prior observed cases, then it certainly wouldn't be thought to be impossible. Instead it's just that theory can't yet explain how. In the same way that it is, or was, ludicrous when people say it's impossible that bumble bees can fly, when clearly they can. Instead our understanding of their flight mechanics was incomplete.
- papreclip 7y agoMaybe he didn't word his post perfectly but he's still pointing out an important distinction. If you could conjure a star of 0.001 solar masses, or one of 1000 solar masses, the first would be a gaseous planet incapable of sustaining a nuclear chain reaction and the second would produce enough energy to overcome the force of gravity at its periphery, blowing away its outer mass and shrinking. Those masses are impossible for stars A 1000M black hole would be stable, there's just no likely way to end up with one in the first place.
- eloff 7y agoAh but even the extremely unlikely is likely to happen many times in a universe with such a mind bogglingly large number of glasses and stars. Such as primitive life evolving into conscious intelligence capable of measuring the minute disturbances from distant black hole mergers. I would have been on the nature finds a way side of the wager.
- wtdata 7y agoNo, it is of a mass that according to our still standing understanding of astrophysics, is impossible to create by the collapse of "a single star". But you can very well have this mass by the colapse of two black holes, or by one black hole that ends up consuming one or more stars nearby in due time.
- 7y ago
- sandworm101 7y agoAlso misleading because it is not that the existence of these holes is physically impossible, rather that their formation was extraordinarily unlikely. They can exist along a range of masses, and it is technically possible to make nearly any mass in the range by merging holes. It just very difficult to imaging how such mergers would have happened.
- CarlosCabrito 7y agoThe title doesn't seem to be misleading, it seems to be boardline. How would you re-write the title in a way that is engaging and still gets the point across?
- tzs 7y agoFor those wondering what the heck you are talking about, it appears that this criticism is of the title of the actual article, which is "Possible Detection of a Black Hole So Big It ‘Should Not Exist’". I don't know if that was also the HN title at some point, but now the HN title is "Possible detection of a black hole with a mass that was thought to be impossible".
- gameswithgo 7y agoon hackernews the top voted comment is always either * pedantic quibble with title * criticism of style of website on mobile it makes this kind of a silly place.
- _jal 7y agoDon't forget the "I agree with you substantively, but aesthetically I must object" genre of political critique.
- dang 7y agoThat made me curious to look at the current top comments. Here they are: https://news.ycombinator.com/item?id=20822461 https://news.ycombinator.com/item?id=20822461 https://news.ycombinator.com/item?id=20822567 https://news.ycombinator.com/item?id=20822567 https://news.ycombinator.com/item?id=20823089 https://news.ycombinator.com/item?id=20823089 https://news.ycombinator.com/item?id=20820337 https://news.ycombinator.com/item?id=20820337 https://news.ycombinator.com/item?id=20822562 https://news.ycombinator.com/item?id=20822562 https://news.ycombinator.com/item?id=20821984 https://news.ycombinator.com/item?id=20821984 https://news.ycombinator.com/item?id=20823146 https://news.ycombinator.com/item?id=20823146 https://news.ycombinator.com/item?id=20823164 https://news.ycombinator.com/item?id=20823164 https://news.ycombinator.com/item?id=20823170 https://news.ycombinator.com/item?id=20823170 https://news.ycombinator.com/item?id=20823062 https://news.ycombinator.com/item?id=20823062 https://news.ycombinator.com/item?id=20821332 https://news.ycombinator.com/item?id=20821332 https://news.ycombinator.com/item?id=20818721 https://news.ycombinator.com/item?id=20818721 https://news.ycombinator.com/item?id=20820497 https://news.ycombinator.com/item?id=20820497 https://news.ycombinator.com/item?id=20822627 https://news.ycombinator.com/item?id=20822627 https://news.ycombinator.com/item?id=20820161 https://news.ycombinator.com/item?id=20820161 https://news.ycombinator.com/item?id=20822859 https://news.ycombinator.com/item?id=20822859 https://news.ycombinator.com/item?id=20818811 https://news.ycombinator.com/item?id=20818811 https://news.ycombinator.com/item?id=20819619 https://news.ycombinator.com/item?id=20819619 https://news.ycombinator.com/item?id=20821850 https://news.ycombinator.com/item?id=20821850 https://news.ycombinator.com/item?id=20818903 https://news.ycombinator.com/item?id=20818903 https://news.ycombinator.com/item?id=20819782 https://news.ycombinator.com/item?id=20819782 https://news.ycombinator.com/item?id=20821601 https://news.ycombinator.com/item?id=20821601 Of those, https://news.ycombinator.com/item?id=20818721 https://news.ycombinator.com/item?id=20818721 is a website style complaint; you get a point for that one. But it's also a classic example that standard moderation would mark as off topic. After doing that, the new top comment is https://news.ycombinator.com/item?id=20820028 https://news.ycombinator.com/item?id=20820028, which is a fine comment. So for this cross-section of stories your description covers 1/30 prior to standard moderation and 0/30 after. That's actually better than most claims of "always"!
- Footkerchief 7y agoThe accurate headline would be: "So Medium-Sized It Should Not Exist"
- luxuryballs 7y agoThere’s really no such thing as “should not exist”, only “this challenges our assumptions”. Anything is possible, it might make the human mind uncomfortable but it’s true. Our ability to comprehend and measure things is so unfathomably finite that it’s almost laughable to think we can be sure of anything.
- ASalazarMX 7y agoOr, hear me out, "The IMPOSSIBLE black hole that science can't explain".
- s_dev 7y agoThought to be impossible* Title is fine -- this is great story. The media are notorious for often make a hames of scientific reporting but this isn't too bad.
- saalweachter 7y ago"So Medium-Sized It Might Have Been Fairly Uncommon"
- Allower 7y agoSomebody missed a conversion I think. 100 solar mass black holes are quite tiny. Supermassive black holes TYPICALLY "[contain] a mass of the order of hundreds of thousands to billions of times the mass of the Sun"[0] [0]: https://en.wikipedia.org/wiki/Supermassive_black_hole https://en.wikipedia.org/wiki/Supermassive_black_hole
- rc_kas 7y ago> But in 1967, three physicists at the Hebrew University in Jerusalem realized that when the core of a dying star is very heavy, it won’t gravitationally collapse into a black hole. Instead, the star will undergo a “pair-instability supernova,” an explosion that totally annihilates it in a matter of seconds, leaving nothing behind. “The star is completely dispersed into space,” the three physicists wrote. Does this mean that maybe the big bang was just a unstable pair that did what they describe?
- NikolaeVarius 7y agoThe big bang might as well be the almighty space chicken laying an egg for all we care before the moment space-time became a concept worth talking about
- jacobush 7y agoSometimes referred to as "God". :)
- earthscienceman 7y agoYou know. I get why this is down-modded... but in the end it's actually a beautifully succinct description of exactly why god is compelling to some people. (Obligatory, "as an atheist" disclaimer)
- chousuke 7y agoAs far as I can tell It's compelling because people tend to dislike uncertainty and making up stories and hypotheticals can feel like knowing. I don't have an issue with that per se, but the pretend "knowledge" tends to get intertwined with all sorts of claims that actually matter, and that bothers me.
- jacobush 7y agoIt's funny it gets downmodded too, considering it wasn't even argument, only an observation. But I'm not here only for upvotes. If my score gets too high I get worried. Edit: Thanks! Can we go a little lower plz.
- cellular 7y agoIn all these situations there are forces and other forces that resist original force but under different ranges. It keeps the universe interesting!
- Retric 7y agoNon clickbait headline: ‘Possible detection of Black Hole that grew after formation.’ Honestly, I would have been more intrigued by the less clickbait headline for novelty if nothing else.
- asdfman123 7y agoIf you don't want clickbait headlines, pay for quality writing in the form of subscriptions. Sign up for quality publications, maybe a few on the local level and a few with a wider distribution, and read articles. Send them occasional letters saying how important those long-form articles are for you, and they're why you're subscribed. If you want high quality, sober writing for free, who do you expect to pay for it?
- mffnbs 7y agoYour comment is oddly confrontational and assumes a lot. Also relies on a societal change that the parent commenter is by no means responsible for.
- sbmassey 7y agoThe tone may be confrontational, but the meaning is basically true.
- asdfman123 7y agoIt frustrates me when people complain about the quality of writing they're not paying for.
- ceejayoz 7y agoI can't find any indication this publication offers a subscription, and I'm not sure how you know /u/Retric doesn't subscribe to various outlets already.
- eesmith 7y agoIs it not okay for me to complain about the quality of Baum's "The Wizard of Oz", which I downloaded for free from https://www.gutenberg.org/ebooks/55 https://www.gutenberg.org/ebooks/55 ? But, more to the point, Quanta is a nonprofit foundation-funded publication. It doesn't have subscriptions or advertisement. If we take your advice, does that mean it's unacceptable to complain about the quality of any Quanta article at all? Doesn't their non-profit status means they receive some (indirect) financial support from us already?
- dsr_ 7y agoSgr A* is thought to be 4+ million solar masses. GCIRS 13E, 3 ly away from Sag A*, is thought to be 1300 solar masses.
- pavel_lishin 7y ago> (The million- and billion-solar-mass supermassive black holes that anchor galaxies’ centers formed differently, and rather mysteriously, in the early universe. LIGO and Virgo are not mechanically capable of detecting the collisions of supermassive black holes.) Is this because those collisions would be too "loud", in the same way that I wouldn't expect my microphone to be able to pick up an earthquake?
- ceejayoz 7y agohttp://www.astronomy.com/news/2019/07/colliding-supermassive-black-holes http://www.astronomy.com/news/2019/07/colliding-supermassive... > If the theories are wrong and there is no problem, supermassive black hole pairs should approach each other and merge frequently enough to create a background “hum” of gravitational waves. “This noise is called the gravitational wave background, and it's a bit like a chaotic chorus of crickets chirping in the night,” Goulding said. “You can't discern one cricket from another, but the volume of the noise helps you estimate how many crickets are out there.” But this hum is outside the hearing range of LIGO and VIRGO, though astronomers are looking forward to projects like LISA, a space-based gravitational wave detector that will “hear” at frequencies current instruments cannot.
- jessriedel 7y agoSupermassive black holes are larger, so the characteristic timescale of their dynamics is longer, and the gravitational waves generated by their merger are correspondingly of lower frequency. More specifically, supermassive black holes binary (SMBHB) mergers usually ring at 0.1-1 millihertz, whereas LIGO's sensitivity is concentrated around more like 0.1-1 kilohertz, a typical frequency of stellar-mass black holes binary mergers. The ~6 orders of magnitude difference comes directly from the fact that supermassive black holes typically weigh in at millions of stellar masses. See the plot here: http://www.tapir.caltech.edu/~teviet/Waves/gwave_spectrum.html http://www.tapir.caltech.edu/~teviet/Waves/gwave_spectrum.ht... (To convert from wavelength (meters) to frequency (hertz), take the speed of light and divide it by the wavelength.)
- lugg 7y ago
- tehsauce 7y ago"LIGO and Virgo are not mechanically capable of detecting the collisions of supermassive black holes" Anyone have ideas why this might be?
- skykooler 7y agoThe larger black holes have a lower frequency chirp. Supermassive black holes would produce a peak frequency so low it gets filtered out as noise.
- ISL 7y agoIt isn't filtered out as noise, but rather drowned out by noise. See Figure 5a: https://arxiv.org/pdf/1604.00439.pdf https://arxiv.org/pdf/1604.00439.pdf
- dron57 7y agoBecause of the lower frequency that would result from the much larger mass collision of the supermassive black holes. Ideally we would have much longer travel distances for the gravity wave detection experiment. They work by building a giant interferometer with lasers pointed at mirrors that try to estimate how spacetime gets bent by the gravity wave. This should be easier to do with larger distances and less sources of noise in space. LISA is one such project. So hopefully in a couple of decades will know a lot more about supermassive black holes and other huge phenomena after detecting their gravity waves!
- wtdata 7y agoThis title is sensationalist. Of course there are black holes with a lot more than 50 solar masses. It's just that they aren't created in a single event by the death of a star. https://en.wikipedia.org/wiki/List_of_most_massive_black_holes https://en.wikipedia.org/wiki/List_of_most_massive_black_hol...
- ajuc 7y agoThey can't be created from stars 50-130 solar masses, but they can be still created by joining 2 black holes of smaller masses, right? The bet seems stupid when you consider black hole in center of Milky Way is supposed to be 4 million times solar mass. So the prediction was wrong.
- phkahler 7y agoThe collisions they're detecting are exactly the kind of events that can create something of the forbidden size. I think the claim is that those objects should not be near another black hole for a subsequent merger?
- Accujack 7y agoIf you read the article, you'd find out that the supermassive black holes like those at the center of our galaxy were formed very early in the Universe's life, when the laws of physics were different.
- Aardwolf 7y agoIt's the same laws but at higher energy level. Depends on how you look at it I guess? Would you say the laws of physics on the moon are different because you can jump higher?
- im3w1l 7y agoThis "when the laws of physics were different" really pisses me off. It makes it sound like gravity pushes you away and magic is real and stuff.
- coldtea 7y agoQM has even stranger effects, so there's that...
- ethbro 7y agoInaccurate, but a close enough approximation for values of "laws of physics" that equal "things we can experience in our universe." Mathematically? No. Practically? Yes.
- _bxg1 7y ago> Systems programming is the development and management of software that serves as a platform for other software to be built upon. What a wonderfully concise definition. I was never sure exactly where to draw the line; "You know, it's, uh, programming where you have to manage memory. They use C for it. It's lower-level, and stuff. It's operating systems but not just operating systems."
- cheschire 7y agoAh, the one Inigo dreamed of.
- 0xFFFE 7y agoSo if I am understanding this correctly, lower threshold (in terms of mass) for a star to become a black hole is lower than what was earlier thought?