I don't like to give comfort to tinfoilers
But it would be an elegant solution to the Fermi Paradox. Any sufficiently advanced species starts mucking about with particle accelerators and soon builds one that gobbles them up.
Here on the Reg Large Hadron Collider (LHC) desk, where we follow the rollercoaster triumphs and disasters which occur at the world's mightiest particle-thrasher, there are occasional quiet spells. Right now, for instance, the titanic machine is shut down for a couple of days' technical tweaks. On such days we cast about us …
If the black hole escapes, the chance of it striking the moon or sun are just ridiculously tiny: draw a sphere around the earth, that just includes the moon. Let's use spherical coordinates. The moon typically occupies 1/2 degree of the sky, so in our spherical coordinates that's 1/720th along the phi-axis and 1/360th along the theta-axis, or roughly 4 chances in a million of striking the moon. The sun has about the same half-degree appearance in the sky, so similar chances of being hit.
Most of space is empty.... hence the name.
Tiny Blackholes are constantly being formed and then explode. If they didn't, they would have collected in the center of the Sun long before now and gobbled it up.There are much more powerful collisions at the Center of the Sun than we could ever make here on Earth in a Lab. My biggest fear from Tiny Blackholes is that they may explode with the force of a hand grenade. It is possible they they could be formed in the LHC and spin out at nearly the speed of light and detonate within milliseconds somewhere within a mile or so of the LHC itself.
I understand sweet cock all about subatomic physics or indeed any of this cosmic stuff, but even I can see a flaw in his argument...
Surely a black hole has no more gravitational attraction that the matter it was originally made from? If you collapsed the entire planet into a singularity wouldn't that singularity still have the same gravitational pull as the planet, pre collapse? So if you collapse some tiny particles into even tinier black holes then those tine black holes would have no more ability to eat the planet than the original particles. And since these particles are already present and the planet hasn't been eaten does that not disprove the good Doctor's theory?
Actually, your post displays some of the traits that make a good scientist:
You admit that there are things you do not know;
You do not profess absolute certainty in what you do know;
You start with simple, common-sense questions based on things like the conservation of mass/energy;
You address them with things that are known empirically.
If enough people thought like that, we might not have a Tinfoil Tuesday.
I think its about the seperation - a singularity has infinite density and zero size / radius so as the gravitational attraction is inversely proportional to the separation distance, other particles can get so close that the gravity is much higher. It only needs to eat enough other particles to outweigh the energy of the hawking radiation and it will keep growing forever. Then again, I may not have much more idea than you. No doubt some more boffinly commentards will sort us out shortly ....
The singularity is effectively a point, but that's not the important criterion. The event horizon is; that is the point at which the escape velocity reaches the speed of light. A massive black hole has a large event horizon while a tiny one has a very small one, but every event horizon has a definite and finite size.
As the radius of the event horizon drops, the gradient of the gravitational field gets steeper. That in fact is what drives Hawking radiation and the enormous energy output of a microscopic black hole. It's also why a supermassive black hole will last for trillions of years while a microscopic one vanishes in a tiny puff of logic and a flash of gamma radiation.
Now if they report on your report on their report and someone then reports on that report of your report on their report of your report of their report reporting on this report Rinse&repeat
Ummm will we create a black hole and all disappear into Paris before the LHC?
Sometimes, some articles, provoke such thought and emotion that to actual express anything becomes impossible as everything tries to run out of your mouth like a room full of school kids completely failing to leave through the door at the same time. Would be nice to have a Wittgenstein icon or failing that a Tex Avery dropped-jaw icon for such moments...
I always find these tinfoilers so funny.
Lets look at his argument - although these collisions are happening all the time with cosmic rays hitting earth particles, his excuse that this doesnt create black holes is that - they do in fact but the momentum of the cosmic ray diverts them away at extremely high velocity. Funny how we dont see these black holes at all (flying away from as often as they are), or the ones that come from other planets in our solar system, or other solar systems for that matter. the ones from other solar systems would surely come flying through here every now and then and probably would have collected more mass and become somewhat bigger by now, you would think wouldnt you? But no we dont see any of these... hmmm...
But no the LHC is dangerous because your hitting 2 particles head on, and so there will be no momentum for the resulting black hole to be propelled away from us and so it will stay and kill us all! Umm so what happens to all the cosmic rays that hit head on in space directly above our heads. Ok its probably not that common but surely were talking at least 1 every 10 years or so somewhere in the vicinty of Earth? Have you seen any black holes sitting around earth recently? They dont have any momentum anymore so they should just be sitting around too, eating everything in sight, like a fat kid at a childrens party... but nope i dont see any around, do you?
I somehow dont think i will be worrying too much just yet, even with the good docs theories...
The fact that white dwarfs and neutron stars actually exist is proof enough that "black hole eatout" is not going to happen anytime soon as these objects have not yet captured anything in spite of having a density compared to which our Gaiaball is akin to a light smoke.
Still, compressing the Moon into a Black Hole? That would be awesome! But I am sure you better be on the far Earth hemisphere during the last second of infall unless you like being a crispy critter.
Surely the best reason not to destroy the planet....
"And CERN is the good uncle of the planet. And they would destroy this World. They would lose all credit with a majority of young people on the planet."
CERN..please don't destroy the planet - you will lose all credit (credibility?) with the young...only a majority mind you - not all of them.
Black holes were predicted in the 18th century using Newtonian gravitation and (as it happens) the (Schwarzschild) radius of the event horizon is the same as that deduced under general relativity. It's hard to avoid the conclusion that a sufficiently large and dense object will have an escape velocity greater than the speed of light.
For further reading, I can recommend "An Introduction to Modern Cosmology" by Andrew Liddle, which tackles many of the aspects of cosmological theory without the need for Tensor Analysis.
If by "predicted in the 18th century" you are referring to the Michell-Laplace dark body, no they weren't. This is a misunderstanding of the definition of escape velocity. This and other errors in black hole theory are explained in accessible form here: http://www.ptep-online.com/index_files/2006/PP-05-10.PDF
Schwarzchild's paper is here: http://www.sjcrothers.plasmaresources.com/schwarzschild.pdf
Hilbert's (commonly but incorrectly referred to as Schwarzchild's) is here: http://www.sjcrothers.plasmaresources.com/hilbert.pdf
The black hole theory and its history are a neat example of how failure to examine the underlying assumptions of a theory leads to false conclusions. Once the erroneous basis is commonly known, academic reputations based on the false conclusions will be wiped out.
To the person who wanted to know what was at the centre of the Milky Way, it is thought to be a plasma focus in an electrical discharge. This theory is taken seriously by people such as the IEEE and their journal IEEE Transactions on Plasma Science.
Tensor Analysis *is* necessary to understand Hilbert's error and why no fewer than four derivations of the solution to Einstein's field equation are mutually consistent and contradict Hilbert.
I'm no physicist but my understanding is that a black hole is a an uber-dense body held together by the force of gravity.
Following this reasoning, if you DID manage to make a teeny black hole then surely it would be so small that it's gravitational force would also be teeny (it would only consist of a handful of atoms). With such a low gravitational force to hold it together, my further thought is that it certainly wouldn't have enough gravitational pull to drag anything else into it, and indeed would simply dissipate again almost instantly.
Got to be careful of Pooh Pooh you know...
"...never ignore a pooh-pooh. I knew a Major, who got pooh-poohed, made the mistake of ignoring the pooh-pooh. He pooh-poohed it! Fatal error! 'Cos it turned out all along that the soldier who pooh-poohed him had been pooh-poohing a lot of other officers who pooh-poohed their pooh-poohs. In the end, we had to disband the regiment. Morale totally destroyed... by pooh-pooh! ..."
It (and every other star in the sky) represents a far more convincing demonstration of CERN's basic argument (that nature is doing this all the time without destroying anything). The sun is a far bigger target and has a dense core of particles moving at very high speeds. The chances that no "mini-black-hole" has ever been stopped dead in its tracks somewhere in the sun's core at some point in the last 5 billion years are surely pretty small.
And yet the observational evidence for stars being short-lived objects is pretty thin.
CERN's safety report (it's on their website) says "it is expected that all black holes are ultimately unstable" and their "expected lifetime would be very short."
So, if everything is as 'expected', then CERN finds out some more about the universe than they know now; but, if not , then we all get to die in a way no-one has ever died before.
I wonder if there's anything they haven't thought of...
Eating the Earth in a few years? I think not.
A black hole located at the centre of the Earth would swallow the entire meaningful planet in less than an few hours if it didn't evaporate... So long as it has an event horizon matter would fall into it under the force of the planets own gravity... that collapse would happen now if it wasnt for the pressure of the inner atoms repelling the ones higher up against the force of gravity...
If there was an event horizon there would be no atoms able to affect an opposing pressure, the whole planet would fall towards the centre and pass through the event horizon unopposed... Even if the mass of a black hole did not increase as more matter fell into it, the whole earth would soon be going bye bye as the effect of its own gravity being centred at the core would accelerated the contents of the planet towards the black hole.
By the way El Reg, if you wanna advance the cause of science, start linking to Richard Muller's PFFP.
Mark, if you want to advance the cause of science how about starting with some simple maths:
1. Given the collision energy at the LHC what is the diameter of the event horizon if a black hole is created?
2. How does that compare to the diameter of electron orbit around the proton/neutron core of an atom.
3. Therefore, as the blackhole oscilates from one side of the earth, through the centre, to the other side just how much matter is impacted by the event horizon?
Clue: it's very, very, like you-know *very* small...
All perfectly valid points - but I was actually considering the matter from a theoretical standpoint of a black hole at rest. There are a few things you may wish to consider though:
1) 15 TeV is the energy of individual proton collisions - not the entire beam. There is the possibility that the whole beam would be deposited through the singularity in less than 100 microseconds.
2) You presume that nothing but the singularity is stationary - this is not the case. Consider the enormous heat underground - Once you get to the mantle you're talking between 500 and 1000 Celsius. That is a *lot* of kinetic energy moving a lot of very dense matter about - significantly increasing interceptions with the event horizon.
3) Even beyond the event horizon there are forces which would accelerate additional matter towards the singularity.
So yes, while your points are well taken, and while I do not think that the LHC is going to implode us, the sun, or anywhere else for that matter... I do think there is a lot more theoretical discussion to be had on the matter.
Even if I believed "black holes" existed i wouldn't be worried about the LHC.
And if it does end Humanity, oh well, its not like we haven't had the ability to start some colonies elsewhere in the solar system for a long time now.
Bootnote; the equations for "black holes" require some special case tinkering to allow them to work. Most physicists will tell you that when an equation yields infinite values (gravity, density) as part of its solution you need to check your equation and starting assumptions.
Super massive objects with super luminal escape velocity's I can accept, infinite gravity/density at the core of it? No.
the coming collapse of the Earth into a marble-sized black hole will mean that we won't have to pay off all those budget deficits that are being racked up!
Paris--because, like a black hole, she's dense, attracts things (pageviews, celeb boyfriends, paparazzi) and her arrival has been heralded as the harbinger of the end of our civilization...
I instinctively distrust any mechanism named after the person citing it as a reason for/against something happening. "Hawking" radiation just happens to be the excuse Professor Hawking gives for the evaporation of black holes, does it? How convenient!
Not only that. I believe that the cosmic ray black hole menace is a reality, and that I was hit by one such infalling microhole only this morning. It passed right through me, of course, but in doing so took out the neuron responsible for knowing where my car keys were and made me late for work.
But of course such empirical proof is nothing to the so-called scientists of today, who require people have labs and staff and grants and gangs of sycophants and the ability to do hard sums before they'll listen to reason.
because I believe the LHC doesn't exist! WHERE'S THE PROOF? Has anyone actually seen a proton collision? Sure we have pretty computer-generated pictures, but I also have computer-generated pictures of giant pliers over Bromwich, which PROVES that the LHC is FALSE.
Therefore, no threat from micro-black holes, except for the accounting black hole - where's the money going?
"How We Lost The Moon, A True Story by Frank W. Allen" was in the Peter Crowther (PS Publishing) edited anthology Moonshots and was collected in Dozois' 17th. Here Paul J. McAuley describes how an experiment on the Moon goes badly wrong, as a black hole is created which begins, inexorably, to feed on the Moon itself.
(Of which I will say no more because you really do not want to know.)
Oh hell, fire that sucker up. Micro black holes?
Last week they were experimenting with stranglets*.
Strangelets for God's sake.
Go out and Google quark stars and strangelets.
Who cares about some pansy ass black hole?
*We are all going to die.
Hawking formula for temperature of black hole T = (hbar c^3) / (8 pi k G M) can easily be transformed to T = (hbar g) / (2 pi k c).
Compare it with Unruh formula for the temperature of accelerated rod T = (hbar a) / (2 pi k c).
If you use the Bell paradox for rods of different length you will come to conclusion that T=T(r).
Using mc^2=hbar c / R_c one can receive the temperature at the depth R_c:
T = mgR_c / (2 pi k).
Or at the any depth R, if g=const:
T = mgR / (2 pi k).
Or in differential form:
dT/dR = mg /(2 pi k).
Changing the depth R by the distance from the center of gravitating object, r:
dT/dr = -mg /(2 pi k).
This is a formula of gravitational gradient of temperature! It was received in the analogues form by Loschmidt and after by Tsiolkovsky and by … and by me in the form:
dT/dr = -(2/5)mg / k.
This temperature gradient does not lead to thermal exchange. This temperature gradient is quite good proved by the experimental observations.
So, there is no any process of BH evaporation. Hawking formula describes the luminosity of usual stars.
The most dangerous objects are not black holes, but magnetic holes or condensates of strange matter.
The amount of dark matter in the Galaxy is 6 times bigger than the usual barionic matter. Contact of microscopic droplet of dark matter with ordinary matter will transform the Solar system into a cosmic corpse.
I give 50% probability that CERN will explode the Earth in a couple of weeks. The 30-th of March it will collide protons with the energy 2*3.5 TeV.
The "fast moving and so they cannot be captured" argument against possible BHs produced by cosmic rays fails when you consider Neutron stars. The have densities at or above atomic nuclei and would easily trap any BH produced when a cosmic rays hits them. Since we have never seen one disappear, and have known some to exist for thousands of years, this puts a rather large holes in that theory as well.
As I tell my students when they ask - the only time that you should worry is when you see large numbers of us particle physicists boarding rockets for the moon. Until then you can be pretty certain that we are not going to do anything dangerous to the Earth. This worked fine until one student asked whether that was why CERN had a space plane - thank you Dan Brown! (and no we do not have a space plane - otherwise I would not spend my time crossing the atlantic to do shifts in economy class!)
"As I tell my students when they ask - the only time that you should worry is when you see large numbers of us particle physicists boarding rockets for the moon."
You really are a particle physicist, aren't you? With no concept of what reality actually involves?
What rockets? What would you do there? Eat cheese?
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