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Micro-Black Holes Make Poor Planet Killers
astroengine writes "Physicists are getting excited about the possibility of micro-black holes (MBH) being produced by the LHC and an international group of researchers have done the math to see what kind of impact they could have on the Earth. Unfortunately, if you're a megalomaniac looking for your next globe-eating weapon, you can scrub MBHs off your WMD list. If a speedy MBH is produced, flying through our planet, it will only have a few seconds to accrete the mass of a few atoms. It would then be lost to space where it will evaporate. If a slow MBH is produced, dropping into the Earth where it sits for a few billion years, the results are even more boring."
I guess I know what kind of girl to look for now ;)
U+F8FF
Like a lot of advanced theoretical physics, this is nothing but speculation heaped upon more speculation.
Just because their math suggests this to be the case, doesn't mean that it actually is.
With some of the math used, there are literally only three or four other theoretical physicists in the world who can "comprehend" it. At that point, one has to wonder if they actually do comprehend it, or just claim to.
Sorry, but I really feel the need to be afraid of something irrational.
Or it destroys the whole planet!!!!111!!11!!1!!
All your 09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0 are belong to us
Ironically, it sucks to be them :)
Summation 2
Sadly however, people will read this article and will still freak out about how the LHC is going to doom us all.
-- Wiccan Army, 13th Airborne Division "We will not fly silently into the night"
How much red matter does the LHC use anyway?
And where exactly does the MBH evaporate to? Or is that all part of the mystery?
I'm sure there's somebody on /. who can answer this:
Correct me if I'm wrong, but I thought to be a black hole you had to be 2 things.
1. a singularity
2. heavy/massive enough to stop anything from escaping
If you've got a singularity (worst case in our example) that's the mass of the earth, how's that supposed to stop any light/matter/etc escaping? It's not massive enough!
or am I missing something.
Also, please excuse my lack of correct terminology. IANAAP
this post is now diamonds!
Sure, everyone's a physics expert even when dealing with completely unknown phenomena and experiments conducted for the first time in human history.
Of course they're saying there is no cause for concern, it's their job that's on the line. Risks to humanity, the planet etc. be damned, we want our LHC!
But http://en.wikipedia.org/wiki/Earth_(novel) was such a good book, why must MBH be so boring in reality?
This is completely safe. We know what's going to happen, that's why we're building these expensive machines to perform experiments. (Yes, I know that doing something catastrophic with the LHC is very very unlikely, but it's an experiment after all. It's not like scientists have never fucked up before, is it?)
Well, the key isn't just mass, but also radius. Gravity (I'll go newtonian, just because I'm lazy) increased linearly with mass, but decreases with the square of the radius. So for example, if you packed something the mass of Earth in just half the size of Earth, the gravity on the surface would be 4 times that of Earth. Squeeze it into a quarter of the size of Earth and get 16 times the gravity on the surface. Squeeze it small enough and you have a black hole.
If you do the proper maths, the Schwarzschild radius of a black hole with the mass of Earth is about 9mm.
Which really means, don't think something that will suck matter and bend light spectacularly all the way to Alpha Centauri. It means that if light happens to go within 9mm of that singularity, it ain't coming out. But farther away, it's still a body with the mass of Earth. The moon's orbit will still have the same radius for example.
A polar bear is a cartesian bear after a coordinate transform.
I don't doubt the science behind the LHC or the scenarios presented. But I wonder if it is possible to make a device (probaby insanely expensive and massive like the LHC) whereby the MHB could be accurately force fed like a veal calf untill it hit a critical point (tons - ktons - Mtons) of mass and would be a worthy earth destroyer. Nuclear weapons just destroy a little area and make the world far less habitable. A good size black hole could
What people don't realize is that this study was funded by companies that produce black holes.
This is my sig.
You can't crush something with a force that's weaker than the repulsive force that's holding it apart.
Gravity is much, much weaker than the subatomic electrostatic forces that hold subatomic particles apart.
In essence, what you're claiming in a black hole is a neutron star – a single massive nucleus – packed together as tightly as is physically possible for matter to be packed. This is impossible on the most basic level: the larger an atomic nucleus gets, the more unstable it is. There are no stable atomic nuclei any larger than lead-208.
Alexander Peter Kristopeit bought his basement from his mommy for one dollar.
This sucks.
can we use a micro-black hole to power a stargate? as ZPM's are hard to find.
Interesting. I haven't met a serious person who was freaked out by the black holes which could possibly generated by the LHC. Actually they are more afraid of the weak economy or the pigeon-flu (which they are more afraid of the vaccine than the actual disease). I guess the most of them who actually know that there is an LHC do not really think a lot about it as there are more pressing matters.
The problem is, there is cause for real concern. Maybe not with the LHC but with science in general. 1. The universe is vast, and old. It's quite clear that, if life is as common as we think it is, the universe should be filled with ancient civilizations. 2. We have no evidence of any alien life... where are they? 3. We have a very rudimentary understanding of physics. 4. It may very well be that it is common for civilizations to evolve to the point at which we are at but then mistakenly destroy themselves through, what at first appear to be benign experiments. Not saying it will be a micro blackhole... or even the LHC. But we had better watch it. There might be a very simple reason that SETI hasn't found anything yet. They're all dead.
This is what happens when a micro black hole is observed too often. Sorry if all the links are down. I tried!
..that he's got to be wrong.
TFA's author has surely done his black hole research. Quoting:
"What's more, I haven't seen any black holes float around my neighborhood recently."
I'm sure he meant some kind of gravitational lensing effect, or maybe some kind of high-energy radiation from an accretion disk or gas jet.
Yeah, but those are the same people who think aliens are traveling across the vast distances of interstellar space to play ass-grab with rednecks in trailer parks. You have about as much chance of educating the unwashed masses as you do of convincing them to become washed masses. Best to keep sedating them with sports.
SJW: Someone who has run out of real oppression, and has to fake it.
Am I the only one who reads MBH as mega black hole, not micro black hole? It's confusing. If the prefix is micro, it would make sense to use a letter that actually means micro, instead of a letter that represents mega.
"... if you're a megalomaniac looking for your next globe-eating weapon,... a speedy MBH ... flying through our planet... will only have a few seconds to accrete the mass of ... the Earth ."
WE'RE DOOMED!
Finally had enough. Come see us over at https://soylentnews.org/
Sam Hughes will be so disappointed
-- 'The' Lord and Master Bitman On High, Master Of All
Come on guys, this is not rocket science!
If you don't know what AltaVista is (was), get off my lawn.
Black-holes are not a source of energy (excluding the monumentally tiny energy output via Hawking radiation), any energy gained harnessing black-holes would be from the accretion disk around them in which particles accelerating towards the black-hole emit radiation due to friction among themselves. However, you'd likely need a stellar-mass black-hole to get a realistic accretion disk going.
Anyway, ZPMs aren't hard to find, you just need Ancient-built replicator civilisations or time travel.
used a time machine made with mini black holes, in case you guys have forgotten..
I'm more worried about the possibility of a resonance cascade.
Dewey, you fool! Your decimal system has played right into my hands!
...where it will evaporate...
I'm no physicist, by any stretch of the imagination, but black holes "evaporating" just doesn't sound right to me.
Proverbs 21:19
There goes another billion dollars. Back to the drawing board.
Meh.
Why worry? I am a firm believer that causality is forcing the LHC to not work, since if it did, it would un-create itself across the entire timeline.
Anyone called?
Mod points are a dangerous tool. Abuse them wisely.
Well, yes, any matter you throw at it (and energy converts neatly to matter too) can only cause it to grow. But there's still the problem of how much and how close.
But, really, let's do some simple maths.
Let's say we want to produce a black hole the size of a helium atom. You know, big enough to occasionally actually bounce into stuff and gobble it up. (Remember, only matter coming closer than the Schwarzschild radius is actually gobbled up.) It's not a big black hole, but it has the potential to grow. So we apply:
r = (2G/c^2) * m ... Where the thing in brackets is approx 1.5 * 10^-27 m/kg. We'll want to get a hole measuring 3x10^-11 m. So we'd need a mass of 2x10^15 kg, or two millions of millions of metric tons.
Yep, that huge a mass will only gobble stuff up if it comes within 3x10^-11m of it. But it's a start, and as an evil genius you may have to start small ;)
To produce that hole, the protons we throw at it, as a total, will have to have the equivalent of that much mass in energy.
Let's transform that into MeV though, since we are talking energy. 1MeV is about 1.8x10^-36 Kg. Let's round to 2x10^-36, since we're only doing a back-of-the-napkin calculation, and are only interested in rough ballpark figures. So we're talking about 10^51 MeV
If we got that energy from uranium, and assuming that we could (A) split every single U235 atom, and (B) capture 100% of the released energy, each atom split releases 180 MeV. (RL reactors don't come even close in both aspects.) Again, let's round it up to 200. (In my fantasy land, reactors are better than 100% efficient;)
That works out to about 5*10^48 uranium atoms split. Avogadro's number being about 6x10^23, that's about 10^25 moles of uranium. (Again, I'm only interested in the order of magnitude. Plus, we rounded up in the other direction before, so it evens up.) And a mole of U235 weighs 235 grams, or about half a pound or almost a quarter kilo.
We're talking about 2 to 3 times 10^24 kilos of uranium, or 2 to 3 times 10^21 _tons_ of U235. That's 2-3 thousand billions of billions of tons of U235. Or about a hundred thousands of billions of billions of reactor-grade enriched uranium. Completely used up in a 100% effective reactor.
So basically yes we _could_ make a bigger black hole by keeping throwing stuff at it, close to the speed of light, but the energy requirements are nuts even to get a hole the size of a helium atom. We don't even _have_ the kind of reactors and capacitors where you could split a hundred thousands of billions of billions of reactor-grade uranium and dump it all into just creating a black hole.
A polar bear is a cartesian bear after a coordinate transform.
It's good to know that they can still be used to kill your nemesis and NOT destroy the Earth (or Mars).
"As God is my witness, I thought turkeys could fly." A. Carlson
If a black hole absorbs all within its gravitational field including energy (light) , then how exactly does it evaporate?
- Zav - Imagine a Beowulf cluster of insensitive clods...
TFA calculates the likely results based on higher dimensional brane physics. It was done earlier in more classical relativity maths and the results summarized in Alan Boyle's Cosmic Log. The max mass was greater and thus life time longer. Still, mass and accretion never crossed the limit that would allow it to reach whatever they call critical mass for these thing. The example given was that if it were charged and it were trapped within the electron cloud of an atom (both conditions lending it additional life span), it would circulate there on the order of weeks before encountering an electron which it could then consume. Even if it did so it would evaporate before it could hit the run away point, and would likely evaporate before eating even one electron. The specific results were different but the conclusion the same - too small to live long enough to do any damage.
Another point made in Cosmic Log (I don't recall if it was the same person/calculations) was that quantum black holes (a more correct descriptor than 'mini-') of the mass and life span hypothesized would be likely to occur regularly in the atmosphere due to incoming primary cosmic rays. Those have been impacting the Earth for billions of years, and we're still here. The hypothesized Hawking radiation is not obvious, thus these may not even be occurring. In any case, their creation would be a highly improbable event.
That last assertion is strictly conjecture based on calculations by my Brambleweeny 57 sub-meson brain. Now if you'll excuse me I'm for a nice hot cup of tea.
"I may be synthetic, but I'm not stupid." -- Bishop 341-B
They only talk about the black hole being unable to suck anything in because its mass is to low, but what abbout atmospheric pressure pushing matter into it and growing it like that? It might be to weak to feed itself but if its forcefed matter deu to pressure in the atmosphere, it should still grow.
This isn't strictly true. In principle it's possible to extract energy directly from the ergosphere of a rotating black hole -- regardless of whether or not there's an accretion disc there. This is known as the Penrose process and it's been known for a good length of time (since the mid 60s, I'd guess, soon after the Kerr solution was found). Basically, you fly into the ergosphere and throw matter into the black hole against its spin. If you get it right then you emerge from the ergosphere with more energy than you entered it. The energy you pull out is balanced against the slowing of the hole's spin.
Of course, actually *utilising* this would be extremely tough, but in principle it would work.
(More details could be found in Sean Carroll's lecture notes on GR, in the chapter about black holes, http://preposterousuniverse.com/grnotes/seven.ps)
Sadly however, people will read this article and will still freak out about how the LHC is going to doom us all.
Still, the LHC *can* make an fairly impressive mess of the test chamber area something goes wrong. I'd recommend being at least a few miles away from it while it's running.
http://www.scientificblogging.com/big_science_gambles/interview_professor_otto_rossler_takes_on_the_lhc
And interesting discussion on this that I found. It's very likely that the resulting explosion would "save the planet" as a side effect, but make for a very impressive crater as well.
A mini black hole will only "exert a near-zero gravitational pull on matter" if the matter is somewhat further away that the schwartzchild radius. If it gets anywhere near that then it'll be anything but non zero. After all , if the black hole had almost no gravity it couldn't hold light in and therefore by definition wouldn't be a black hole. I suspect the physicists and banking on the black hole travelling through atoms in the same way that for example neutrinos do - in that the atom to them is effectively empty space with a tiny compact nucleus which is so small that the chances of a direct hit are minimum. We have no absolute guarantee however that a black hole will behave the same way as an uncharged elementary particle.
first Ringworld was claimed to be impossible, and now the same happens with his 70's story "The Hole Man", where what happens is essentially involves a micro black hole falling into a planet. Science is slowly killing hard sci-fi.
A week before they turn it on to produce the MBH and destroy the Earth I will buy anyones home for 5 cents on the dollar so they can spend their last week in a continuous state of Party.
Undetectable Steganography? Yep, there's an app fo
Very true but what if we used the Micro-black holes as a way to jump start the Stargate? Just place a MBH the center of the Stargate, now you don't require as much energy to open a wormhole. I can't say for certain but it very well may be more energy efficient to create a MBH than start up the SG. Also maybe and again I can't be certain but a SC requires a large amount of energy to be used all at once, that requires massive capacity to get it to work; with a MBH you may be able to grow one at a slower rate in other words it requires the same amount of energy but you don't need to have it all at once.
The whole planet-eating-micro-black-hole thing was already covered in David Brin's _Earth_.
I guess some black holes DON'T suck... *takes a bow*
This needs more cowbell!!!
Optic fibers, transistors, structures in modern microchips hitting quantum effects more and more (requiring workarounds), magnetoresistive effect in HDDs, and so on...all speculation to you.
One that hath name thou can not otter
What did they get into the space between G.W. Bush ears then? It sucked everything that mattered and crushed it in some strange space time continuum know as "his presidency". Researchers are still baffled....
Suck! Suck! Suck!
Sorry... :)
Granted that very small black holes cannot eat fast enough to threaten Earth, this raises the question: "How large would a black hole have to be to be a threat to Earth"?
Can any one generate a black hole mass/time-to-eat-the Earth table? Enquiring minds want to know!
Starships were meant to fly, Hands up and touch the sky - Nicky Minaj
we need the gate address to dial them
Sadly however, people will read this article
No, they won't.
So if the earth became a black hole with a Schwartzchild radius of 9mm, would it evaporate and if so how long would it take?
It pays to be prepared
I think the LHC has destroyed the world multiple times now. It is just that we here and now are the survivors of the disasters....
According to the Multi-verse theory, each quantum fluctuation creates a new universe or timeline.....
Because we are alive and well and not consumed by a black hole, that means in "our" branch of the multiverse we haven't created a Black Hole that swallows earth "yet".....
But fear not because Even if the LHC were to create a earth consuming black hole, strangelet, way to lower the energy level entire universe leading to it's immediate destruction. We will survive because at least one branch of timeline will survive by failing to create these anomolies and go on to branch out some more to survive whatever weird physics experiments we dream up of go arwy.....
The only problem is when creating black hols and exotic matter that is large enough to reduce quantum probability and then we are really screwed.
Tsukasa: All I really want, is to be left alone...
I could part with one doomsday device and still be feared.
Gravity is much, much weaker than the subatomic electrostatic forces that hold subatomic particles apart.
It really isn't, not in the way that you mean. Yes the Gravitational Constant is much smaller than Coulomb's Constant, and yes the gravitational attraction between two protons is much weaker than the electrostatic repulsion between two protons.
However as soon as you do anything more complicated than compare two charged particles, things change. The reason is because the two forces bind to different properties of matter, and while the charge property can be both positive and negative, mass is only positive. So while the gravitational force between two hydrogen atoms is very small, it is bigger than the electrostatic force between them because they are carrying no net charge.
Thus gravity can easily be the stronger force in any given situation, because the forces of opposite charges will cancel, while their masses will only add together. Put enough mass together, and the gravitational force can easily outstrip every other force.
In essence, what you're claiming in a black hole is a neutron star - a single massive nucleus - packed together as tightly as is physically possible for matter to be packed. This is impossible on the most basic level: the larger an atomic nucleus gets, the more unstable it is. There are no stable atomic nuclei any larger than lead-208.
Kind of an ironic statement, since the electrostatic force is much, much weaker than the strong nuclear force which holds the protons together, and yet it is exactly because of the electrostatic force overcoming the strong force that these atoms become unstable. Because the strong force is only stronger in the same naive way in which electromagnetism is stronger than gravity.
Also ironic because gravity overcoming electrostatic forces is also responsible for the existence of all of those large, unstable atoms in the first place. Fusing even two hydrogen atoms requires overcoming the repulsion of their nuclei when very close, and it's the intense heat and pressure in the core of a star -- caused by its immense mass -- which allows this. As the star over time fuses heavier elements the energy released decreases until lead where it crosses over into negative. At this point all the fusion energy that was holding the mass of the star up fails, and all that mass in the outer portions of the star collapses in due to gravity, and that transfer of energy fuses atoms much, much heavier than lead and leads to all the unstable elements we find on earth plus many that don't last long enough to become part of a planet.
Gravity, the "weakest" force, creates atoms which the strong interaction, the "strongest" force, cannot hold together!
So, obviously the situation is more complex than just making a blanket statement that one force is stronger than the other.
The enemies of Democracy are
Seems to me that the only possible ways to develop a time machine or starship warp drive are from manufacturing and harnessing Black Holes. We need to poke a singularity in the fabric of the universe to get around some hard limits like the speed of light. The trick then is how to arrange them geometrically to get the desired result (and how to control them to do this). Seems like really worthwhile research.
So it is that, in our version, the electrical meltdown in the LHC saved this universe? For a year...? Have we gotten to the point where because we got scientists saying they can see the swinging stars going around the black hole at galactic center and planets around other stars we think we know anything about physics??! I thought those theories just got a handle on the whole fractoidal, depends-what-scale-you're-at thing about physics down... Folks here post that 'it can't be dangerous, because we haven't seen them when we look out at the stars.' I keep thinking about those sage words: "Space is big... I mean, really big..." They're probably out there chewing on something. But to summon one up next to the only planet we've got is a bit scary.
"I got it all together but I forgot where I put it."
"Physicists are getting excited about the possibility of micro-black holes (MBH) being produced by the LHC"
no, not really. In fact the pretty much dismiss them sine they ran these numbers many years ago.
The Kruger Dunning explains most post on
You are confusing time line branches with the multiverse theory. I will address both:
NOTHING we do in this universe impacts another universe in any way what so ever due to are friend decohesion
Creating a new time line doesn't mean that the new time line can violate physics. So even in a other time lines, the LHC does not destroy the planet.
The Kruger Dunning explains most post on
Actually, in my experience conspiracy theorists don't watch sports, as they feel all matches are fixed by the "elite".
I'd like to add to your redneck ass-grabbing example. I have met numerous people, including a guy I worked with on my last contract, who believed in one or more of:
- an alien lizard conspiracy which secretly rules the Earth
- the global warming "hoax" that is being foisted upon us by ne'er-do-well climate scientists seeking to enrich themselves
- the Bilderberg group of rich people who secretly rule the world (optionally under the watchful eyes of the lizard dudes)
- hollow Earth - not kidding, I met a girl who was way into this piece of nutbaggery
- the Face on Mars people, who have gone silent since the Mars Global Surveyor took better pictures
- "Moon landing never happened" people - I know a girl who works in administration at the local Science World who believes this, and I am not making this up
- of course, all the 9/11 conspiracy people
Etc., etc. These are the types who believe the LHC poses a threat. No science background and probably a good dose of attention-seeking - so why are we even discussing this?
I can remember this being explained in a much better way in the very first article I ever read about the LHC, back when the start of construction was planned for the next weeks.!
It's just that the sensationalist retards of course ignored that part from then on.
Any sufficiently advanced intelligence is indistinguishable from stupidity.
The sun won't ever go black hole because there's not enough mass to overcome the electron repulsion between iron atoms.
The sun isn't big enough to become a supernova either, since the remains of the star AFTER burning all the fusion products would have to be heavier than the sun is NOW (and it will lose mass as it reaches red giant stage).
And since the earth would orbit further away if the sun were lighter but the total energy (gravitational potential + kinetic) were the same for the earth, there's a good chance the earth would spiral out as the sun loses mass into its red giant phase and not get burned inside the sun's larger atmosphere, even though that would extend beyond the current orbit of the earth.
And there's no such thing as "drag" as you describe it. Photon pressure is about 1.6 pounds per square meter at 1 AU. Total force on the earth would be ~2 million pound force. Since the earth weighs 10^21lbs, the acceleration would naff all.
So, no, an object put at earth's position with a sun that was dead (solid iron is the only option, but even if it were a black hole, the idea is the same) it wouldn't collapse in because there's no decay in the orbit.
You've watched Disney's "The Black Hole" and thought it was a documentary, I think.
There's no such theory as one your message proposes someone else to have thought up.
Granted, and definitely interesting, but you could only get out the amount of energy the black-hole has stored in angular momentum. For a microscopic black-hole this would be insignificant.
Oh, definitely. I dread to think of the control that would be needed to fire a beam of electrons against a femtometre-sized black hole's spin and then, somehow, extract energy from, err, whatever's left of the beam. I was reading through Carroll's notes again earlier and read a bit I'd forgotten, you can only at the very most recover 29% of a black hole's energy like that, or a similar number. The rest will always be in its mass. (And electric fields etc.)
I should have emphasised the word "strictly" to make it clear I was being a pedant :)
Perhaps if the holes were charged we could do electronics with tiny little charged black holes. Perhaps not...
So we are trying to investigate something we don't fully understand yet, using experiments never done before, looking for forces of nature never observed like this before, but on a theoretical basis we can say with certainty that there are no safety risks.
Hmmm. I remember accidents happening during the Manhattan project.
In more serious terms, in case anyone believes the parent in spite of its +4 Funny mod:
Obviously the branching universes only happen based on things that are actually possible. There are no branches from me making my morning coffee that result in the destruction of Earth, or unicorns wandering into my yard, or anything like that.
Since the LHC *can't* destroy the earth, no LHC startup attempts are spinning off destroyed-Earth branches.
The Face on Mars people didn't just insist that the new photos were of a different location and we were just told it was the face to stop people from asking questions?
Amateurs.
We hope your rules and wisdom choke you / Now we are one in everlasting peace
Gravitational collapse can do work. The usual example is to consider the collapse of a spherical mass whose outer surface is connected to ropes which in turn connect to electric generators. Collapse tugs the rope towards the centre of the sphere, causing a rotation in the generator, leading to the production of electricity.
Letting anything fall in a gravitational potential gradient does work; by the equivalence principle in GR, gravitation is an acceleration.
The energy to heat the particles comes from the acceleration; acceleration imparts energy; the acceleration comes from the mass-energy of the black hole creating a gravitational potential gradient in which the particles fall.
It is much much less friction than compressive heating (and some inverse compton scattering) that is the reason the gasses near a black hole are hot.
The interaction cross section of a black hole is proportional to the r term in the Schwartzchild solution for the black hole; for radiuses larger than that of a neutral atom, an accretion disk will form in any gas with reasonable pressure. Microscopic black holes have minuscule radiuses that are much smaller than those of free nucleons, and so an accretion could only happen in a very hot and dense fluid (that also must be hotter than the Hawking evaporation temperature of the MBH).