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A dozen black holes may lie at the centre of our galaxy
- lifeisstillgood 9y agoLet me try an optimistic thought experiment. Roughly around the end of the Napoleonic era, call it 1815, 9/10ths of humans lives in what we would call abject poverty. today it is reversed and only 1/10th does. (This is still a travesty, but it is objectively better) In that period we have seen incredible technological, political and economic improvements. But it's not clear if we will continue to see them "we might have invented everything" is a fairly common refrain (if not on HN!) So can we say anything about where we are in this period of chnage - near the end? Well with no other information we can only plump for "in the middle". Which roughly speaking means we expect to see change on the scale of 19th and 20th Century well into the 2200s. And part of my monkey brain just recoils at this ... optimism. My monkey brain does not trust the numbers. But articles like this help me quieten my monkey. We look up into the night sky with powerful telescopes and find events millennia old, light years away and they confirm how we think galaxies are made. We look into the night sky and find Dark matter that we do not even know what it is made of - and I ask my monkey brain, at some point we did not know what was over the oceans, but we predicted new lands, we did not know what the land was made of and they were made of ores and minerals. I am by nature a skeptical optimist, but the awesomeness of astronomy, it's generally leading place in science, still impresses me. It looks like a good two centuries to come. Just sayin' Bibliography: I am probably stealing from people cleverer than i whom I cannot remember to reference or am too dumb to reference Edit: I need to write more clearly. I am not arguing that we have invented everything, just that it can feel "where can the next thing possibly come from?". And Astronomy does things like point out "We can see 13 billion years in every direction, and most of it we don't even know what it is made of. Some of it might be useful :-)"
- axelfontaine 9y ago> It looks like a good two centuries to come. ... if it wasn't for - potential ecosystem collapses due to disappearing bee (pollination), insect (food) and coral populations - rising global instability due to climate refugees - the upcoming end of the antibiotics era - ...
- Donzo 9y ago> "Roughly around the end of the Napoleonic era, call it 1815, 9/10ths of humans lives in what we would call abject poverty. today it is reversed and only 1/10th does." There are now 80% more people (according to these figures) who now have enough food that they can worry about bees. That's a good thing if you ask me. Now about those bees...
- btcindivist 9y agoIf only we didn't waste all of the antibiotics on non-human animals. Such a bad use of brilliant biotechnology.
- Cthulhu_ 9y agoOr freely prescribe them for small ailments (looking at China here)
- btcindivist 9y agoAntibiotics for human use are nothing. There's around 70 billion domesticated land animals being born and dying every year. That's 700 billion Petri dishes with varying antibiotic power in just 10 years, and that number is more than all of the humans that ever lived on Earth. More than enough for some massively superior bacteria to evolve.
- lawlessone 9y ago
- make3 9y agofirst time I hear the "we might have invented everything" thing. that's an interesting contrast to what I'm used to hearing, working in AI, with people always raving about terminators coming and what not
- shawn 9y agoOne way to dispel the idea that everything has been invented is to imagine something small and mundane – but 100 years in the future. It seems unlikely that people will be writing code or picking out groceries the same way they do today, for example. Some aspects will be the same. But are you sure we won’t be picking out groceries in VR? Another thing that helps: technological progress seemed exponential over the last century, but in the long term it’s actually sigmoidal. Progress happens in jumps.
- buvanshak 9y ago> One way to dispel the idea that everything has been invented is to imagine something small and mundane – but 100 years in the future... Hasn't people always thought there were living in the pinnacle of technology era? I mean, if you look at texts that are 50 or 100 years old, you can see people chest thumping about how they are in the modern world. Aren't we doing the same now?
- darepublic 9y agoIf anything the chest thumping of people 50 - 100 years ago was more warranted than anything similar today imo
- jeremysmyth 9y agoNot in the dark ages. Many folks lived in the shadows of ruins made by much more advanced cultures.
- jstanley 9y agoPeople have been saying "we might have invented everything" for hundreds of years. I like the "invention wavefront" analogy, but I unfortunately can't remember where I learnt it. Imagine the high-dimensional space of all possible things that can be invented. In the "centre" of the space is a hypersphere containing everything that has been invented to date. Every new invention is invented by "poking outwards" in one small place on the boundary of this hypersphere (hyperglobule) so that the hyperglobule now contains something that it didn't contain before. All inventions that could possibly be invented right now exist on the surface of the hyperglobule. Think of this as the "invention wavefront". Notice that as the globule expands, the wavefront becomes larger, not smaller. What this means is that as more things get invented, more new inventions become possible (intuitively: you can't invent better brakes for a car until you've invented a car, and so on). "We might have invented everything" would imply that the space of all possible inventions is bounded, and we're running up against the edges of the box. But I don't see any reason it should be bounded.
- placebo 9y agoFor all practical purposes, I agree with the analogy, but would like to point out that the box might not be infinite so there could be limits to invention. Take a chess game as an example. No one would say there weren't creative inventions regarding tactics and strategies to win, but the bottom line is that the number of possible chess games, no matter how staggeringly huge, is still finite. In the end, no matter how intelligent the players, there will be a point were nothing will be left to be invented, so perhaps life is also a solved game in that respect.
- iamgopal 9y agoAlso area of that thought ball increase by square. It means every new invention have tons of application in related and unrelated fields, which may help finds another invention. I think we should be able to invent all that is shown in those Hollywood blockbusters by couple of millenium if not more.
- marcosdumay 9y agoThere is something on the order of 10^100 (~2^300) bits of storage available at the Universe. Is the box larger or smaller than that?
- musgravepeter 9y ago"This century has been so rich in discovery and so packed with technical innovation that it is tempting to believe that there can never be another like it. That conceit betrays the poverty of our collective imagination." John Maddox (former editor of Nature, 1998) https://en.wikiquote.org/wiki/John_Maddox https://en.wikiquote.org/wiki/John_Maddox
- placebo 9y agoI'd like to believe you are right and, without any ability to estimate where we are on what seems like an exponential curve, hope that things are evolving towards the positive at an ever increasing pace. Interesting you should mention monkey brains, because my monkey brain also recoils at this optimism when it understands that most brains are still monkey brains, and I don't trust monkeys that create an arsenal of weapons of mass destruction which can totally wipe out all trace of the things you are rightly passionate about. The evidence is scarce that other than the obvious technological progress there has been any other progress but even that being so, I'm cautiously optimistic that the battle between monkey mind and enlightened mind will eventually be won by the latter rather than monkeys collectively going the way of the dinosaurs. >I am probably stealing from people cleverer than i whom I cannot remember to reference or am too dumb to reference Don't remember which book it was, but I remember reading a book where there was a phrase on a page before the first chapter, "All creativity is subconscious plagiarism" :-) Of course this generality can be logically refuted but it's probably something we all do to a degree.
- slx26 9y agoYeah, that's what I call "creativity". I'd say creativity —without quotes— comes from plagiarising multiple sources at the same time, your past self included, and repeat until the result becomes cohesive.
- grkvlt 9y ago> with no other information we can only plump for "in the middle". This is because the derivative of e^x is e^x, so when undergoing exponential growth the rate of change tells us nothing about where we are on that curve. And this is also why people (not GP, of course) who talk about the 'knee' in an exponential graph really annoy me...!
- smaddox 9y agoDoesn't that mean the rate of change tells you exactly where you are on the curve? Just solve for X. Of course, there's no reason to think invention should follow an exponential over the long term...
- dave_sullivan 9y agoCheck out the Transcension Hypothesis paper by John Smart. It talks about far future civilizations, hypothesizes they would live in or near the surface of (possibly manufactured) blackholes, and that black holes are actually all over the place. It also takes the stance that intelligent civilizations (including ours) would be more likely to minitiarize and grow inwards, rather than exploring and spreading throughout the galaxy as per Star Trek. http://brighterbrains.org/articles/entry/the-transcension-hypothesis-an-intriguing-answer-to-the-fermi-paradox http://brighterbrains.org/articles/entry/the-transcension-hy...
- vkou 9y ago> So can we say anything about where we are in this period of chnage - near the end? Well with no other information we can only plump for "in the middle". Which roughly speaking means we expect to see change on the scale of 19th and 20th Century well into the 2200s. We do have information for this. We are either towards the end, or the beginning. The rapid advance of the 19th and 20th centuries were only possible due to our discovery of nearly-unlimited amounts of cheap, easily transportable energy, in the form of fossil fuels. We've also used up our carbon budget for them (And gone over it, in fact.) There are now three likely outcomes: 1. Renewables reach the break-even point where they can affordably provide ~95% of our energy needs. 2. They don't, and we'll cook ourselves to death with our GHG emissions. 3. They don't, and our grandchildren will be shoveling shit as subsistence farmers.
- Koshkin 9y agoI think there's at least three areas where the possibilities to invent new things are limitless: biology, mathematics, and computer games.
- hellofunk 9y agoTo be honest, in reading this and considering the vastness of space, my initial impression was "what, only twelve?!"
- lawlessone 9y agoBut it means there is probably more they can't see >By extrapolating from the properties and distribution of these binaries, the team estimates that there may be 300-500 low-mass binaries and 10,000 isolated low-mass black holes surrounding Sgr A*.
- OldArrow 9y agoEvery object in the universe attracts any other object. My initial impression was : not only one ?
- bluntfang 9y agowell it almost seems like there are only 2 options: only one and so many we can't possible try to count them all
- Aardwolf 9y agoThis is just about the center of our galaxy though. There are billions of other galaxies in the observable universe, most of those I assume also have black hole(s) in their center :)
- btcindivist 9y agoAre discoveries about black holes legit? Isn't it still the case that they have not been experimentally confirmed to exist, and all talk of discoveries is just conceptual?
- snarfy 9y agoWe have recorded a video[1] of the black hole at the center of our galaxy. [1] - https://www.youtube.com/watch?v=k7xl_zjz0o8 https://www.youtube.com/watch?v=k7xl_zjz0o8
- rjth 9y agoAmazing video!
- aidos 9y agoThat’s incredible! Definitely love to see / hear more about this if anyone has any pointers?
- snarfy 9y agoThe video came from this study - "Monitoring stellar orbits around the Massive Black Hole in the Galactic Center" - https://arxiv.org/abs/0810.4674 https://arxiv.org/abs/0810.4674 the wiki article - https://en.wikipedia.org/wiki/Sagittarius_A* https://en.wikipedia.org/wiki/Sagittarius_A*
- deleted 9y ago[deleted]
- kowdermeister 9y agoNo, they definitely exists, for example: https://en.wikipedia.org/wiki/Cygnus_X-1 https://en.wikipedia.org/wiki/Cygnus_X-1
- azernik 9y agoThey are actually quite visible - their accretion disks (matter falling into the black hole) are very hot and radiate on a broad range of frequencies.
- mar77i 9y agoWasn't this some thing that puzzled cosomologists a few years ago that some galaxies emit GRBs at scary intensities? Suddenly it sounds plausible when we consider that at a certain density of these smaller black holes, the peaceful neighborhood of these other objects and their companion stars can start to get really violent, causing collsions and whatnot which then leads to these GRBs.
- spchampion2 9y agoFrom the article: "A search for the X-ray signatures of low-mass black hole binaries in the Chandra data turned up 12 within three light-years of Sgr A*." Three light years is not that big of a distance in the grand scheme of things. For reference, the nearest star to Earth is Proxima Centauri, which is 4.2 light years away. Having 12 binaries within 3 ly sounds really dense. Having several hundred sounds crazy.
- ttul 9y agoThe night sky at the galactic Centre is white
- mannykannot 9y agoI am sure the region is stunningly starlit, but if it were Olber's-paradox- bright, would not the dust in the region also be glowing white-hot?
- metaobject 9y agoAFAIK, we are unable to see the center of the galaxy with visible-spectrum sensors due to the immense amount of dust and gas. We can see the center with IR sensors, however.
- pdonis 9y ago> the nearest star to Earth is Proxima Centauri, which is 4.2 light years away. Having 12 binaries within 3 ly sounds really dense. Having several hundred sounds crazy. Not at the center of the galaxy. Stars are much closer together on average there than they are way out here in the boonies where we are.
- saiya-jin 9y agoWhich makes me think - if the area is relatively dense with black holes, quite often (on galactic time scale) there must be super close encounters with stars, sometimes BH swinging right through a sun (that might be a bit of a stretch)! Imagine that spectacle, devouring whole sun throwing off/swallowing it potential planets. I am sure we would be able to see it as huge burst with our current sensors. Plus there might be huge amount of smaller and tiny BH wreaking all kinds of havoc to everything. Pretty wild place to be
- everdev 9y agoIs it possible that black holes could account for a good portion of "dark matter"? They literally fit the term.
- dbasedweeb 9y agoThere’s a theory which accounts for that called MACHO, for MAssive Compact Halo Object. While it’s possible, over many years of observation it’s very unlikely. You can’t see a black hole directly, unless it’s “eating” of course, but you can see gravitational effects like lensing. If black holes and neutron stars made up most dark matter, we’d expect to see evidence of it, and we don’t. It is still possible, although Weakly Interacting Massive Particles (WIMPs) are more likely, along with Axions and Sterile Neutrinos.
- wallace_f 9y agoMy heretical theory of dark matter is that is just a byproduct of black holes gravitational effects. Probably something about so much mass punching such a deep curve in spacetime creates a widespread effect. Of course this is just a baseless theory, but it seems more reasonable to consider the possibilities of a realm which we know that we know almost nothing about, than inventing new particles or physics to fit the data. Again, not an educated theory.
- semi-extrinsic 9y agoThe trouble with this kind of theory is that for a force like gravity, if you consider the force outside a sphere surrounding the sun, the force is identical no matter how the mass inside is distributed, whether it's the sun or a solar mass black hole inside the sphere.
- wallace_f 9y agoAt extreme scales gravity may behave in strange and unexpected ways -- as do other phenomena.
- davesque 9y agoI'm sure this is an oversimplified view, but doesn't it seem like, because black holes are more dense, they'd naturally tend to fall toward and gather around the center of the galaxy? Sort of like how more dense objects tend to be found at the bottom of a pond? So then perhaps it makes a lot of sense that the galactic center would contain a lot of black holes.
- Boxxed 9y agoIn a pond, you have the force of gravity (i.e., buoyant force) to do this sorting. This force doesn't exist in space, or at least not in a way that's analogous to the pond.
- davesque 9y agoInteresting. Can you provide any more details? Obviously the force of gravity exists in space. So what's a better way to describe the difference?
- Boxxed 9y agoIn a pond, gravity is uniform in all directions and not dependent on the distribution of objects -- everything is competing to get to the bottom.
- rcthompson 9y agoImagine that our sun suddenly collapsed into a 1-solar-mass black hole. What would happen to the orbits of the planets? Nothing. The black hole would still exert the same gravitational pull as the sun did. The same is true if you replace all the planets with equivalent-mass black holes. Denser objects in an atmosphere or other fluid, where there is friction and buoyancy, will tend to sink to the bottom. However, if you're in the vacuum of space, there is no concept of "sinking". There is nothing to sink in unless you enter the atmosphere of a planet or star. However, maybe there is enough interstellar dust near the center of the galaxy to produce a non-negligible amount of friction over millions or billions of years.
- oldandtired 9y agoSome food for thought. Let me state up front, I am no fan of the "black hole" and "neutron star" concepts so take the following comments as arising from that basis. The x-ray data and observations are only "supposed" to be coming from "black holes" as we cannot and have not directly observed any such entities. Now, it may be that there are specific entities involved that are dark body and gravitationally significant. However, as we are unable to directly observed these entities, they may also be quite visible and as well as gravitationally significant in terms of the effects seen. The current consensus model for the universe entails a belief that General Relativity is correct and at the base of the GR model is a belief that the ONLY significant force at solar, galactic and universal levels is gravity, in whatever form your model of gravity may specifically mean, as in a force or in GR terms a warping of space due to mass. Since we also know that there are large areas of charged space, we need to be able to ask the question - "are these charged space areas of such significance that they effect large areas of solar, galactic or universal space?" The thing that we call gravity is of such weakness that even weak electric or magnetic fields completely override any gravitational effects. The simplest example that I use with my grandchildren is rubbing a balloon against my limited coverage of hair on my head and that balloon will stay connected with my hair against any force of gravity that is around me. Too oft, methinks, the consensus models of the day are considered "holy writ" and ye are considered "blasphemers of the highest order" if one even dares to voice any doubt in those models. We take ourselves so seriously, even though what we should be doing is knuckling down and looking at all the facts before us. If our models are wrong, so what? Is not the purpose of participating in any science a means to getting a better understanding of the nature of the universe around us? If our models are wrong in any area, let's try something else. To me in a sense, we are still in the mindset of those who came before who fought against a heliocentric view, they would rather add more gears to the geocentric model than consider that maybe another model is more useful in describing the world around us. Mayhaps, we need to take some steps back from our current models, put aside our pet theories and just look at the data that we have and see if some other pattern arises. It should be no skin off of our noses if the models and theories we have are shown to be wrong. Let's make science fun again, because it ain't no fun today.