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Why the LHC Won't Destroy the World
An anonymous reader writes "Most people are aware of the recent articles contending that the Large Hadron Collider at CERN might destroy the world. While most scientists have no such concerns, a recent preprint released to arxiv systematically dismantles the notion. The gist of the argument is this: Everything that will be created at the LHC is already being created by cosmic rays. If a black hole created by the LHC is interactive enough to destroy the world within the lifetime of the sun, similar black holes are already being created by cosmic rays. Such black holes would be stopped by dense cosmic objects (neutron stars and white dwarfs). A black hole stopped in one of these objects would eventually absorb it. We see sufficiently old neutron stars in the sky, thus any black hole that could be created at the LHC, even if it is stable, would have no effect on the earth on any meaningful timescale."
First particle?
rewriting history since 2109
Don't they see that there used to be MORE neutron stars?
This article doesn't take into account accidental resonance cascades that open up portals to bizarre alien.
Or "I'm hungry" or "This coffee is awful".
Nerd rage is the funniest rage.
"Oops"
I agree. The world will end not with an alien invasion, not with a famine and not with a multi-national nucler war.No, the world will end with a scientist uttering "Oh, sweet!"
Those who believe the Internet is private,
find their privates are on the Internet.
Interestingly Enrico Fermi did use the same argument while setting on the first nuclear reactor during the Manhattan project around 1940 (that some cosmic rays are anyway much more energetic and bombarding the Earth since ages). And later fission and fusion bomb makers did use the same argument while playing with increasingly powerful toys. Ditto particle physicists for each new and more powerful accelerator. Isn't it time that journalists and other dumb news makers understand?
"We have an unintended event horizon."
Take the cheese to sickbay, the doctor should see it as soon as possible - B'Elanna Torres, "Learning Curve"
I've seen both 'theories' touted in the press. I don't think that most people realise that the LHC, impressive as it is, is generating particle energies way lower than we observe ocasionally naturally.
"Physics is to math as sex is to masturbation." -R. Feynman
Now, now, if you follow standard insertion procedure, everything will be fine. ... Although I will admit that the possibility of a resonance cascade scenario is extremely unlikely.
Tie two birds together: although they have four wings, they cannot fly. (The blind man)
The LHC is "mostly harmless." After all, it's only bashing Large Hadrons together. Now, the Ginormous Hadron Collider (GHC) is another matter all together. It's been giving me the stink-eye for weeks now. I wouldn't turn my back on it for a minute.
Yes, but this can be counteracted via the usage of normalets, which are generated by anybody who doesn't read slashdot.
See also the Review of the Safety of LHC Collisions which also appeared today, and is a more non-technical summary of the safety review.
1^2=1; (-1)^2=1; 1^2=(-1)^2; 1=-1; 1=0.
Slashdot doesn't need to hear all this, they're highly trained professionals. We've assured the administrator that *nothing will go wrong*.
Actually, we'd all die relatively slowly and quickly, depending on if you're looking at people falling in after or before you.
Why is it that physicists on and in favor of this project (and those that are following this story) are even remotely surprised by the "Create a black hole, and destroy the world" rhetoric?
We've heard all the sensational "Black holes are the ultimate destructive force" commentary from Astronomers for decades seen all the cool Black hole animations, etceteras, ad nausium.
In my opinion, all the sensationalism surrounding the Black holes to start with was a ploy for funding. Now that same story line shows it's dark side, and people seemed surprised at the outcry and at overly dramatic fear of the LHC.
I'm not saying that sensationalizing science is a bad thing per se, just that people shouldn't be surprised when it bites them on the ass.
A positive attitude may not solve all your problems, but it will annoy enough people to make it worth the effort.
There are two opposing viewpoints on the matter.
On the one hand, we have particle physicists whose "theories" on the interaction of subatomic-scale matter is drawn from decades of research and experimentation.
On the other hand, we have people who know essentially no physics and seemingly assume that the people building the LHC must be as lost when it comes to science as they. They make the argument, "Well, we don't *really* know what's going to happen."
It's amazing that the latter are able to function, as crippled as they should be of the fear of uncertainty.
Actually we wouldn't. The black hole would not be any heavier than the earth (the moon would continue to orbit it as if nothing had happened, and the black hole would happily circle around the sun). Since the earth's mass is not that impressive, the black hole would have to be tiny, so the area around it where the gravity would significantly bend the universe would also be quite small, making our painful (but swift) deaths rather unspectacular.
Yeah I know. 'WOOOOSH!'
Whatever small compass we shove the matter into, it'll have exactly the same amount of gravity before and after. If we happen to shove it into a tight enough space that it becomes a black hole, it will be spectacularly tiny. It'll only start to accrete matter as it interacts with it. And, it'll have to get close enough to do it.
Gravity being what it is, it seems far more likely that a black hole formed in the lab would get drawn to the Earth's center of gravity (just like everything else on Earth is) rather than causing the Earth's center of gravity to shift. Shifting the Earth's center of gravity dramatically toward the LHC would take way more energy than what we're putting into the particles at the LHC.
Program Intellivision!
Well, exactly how small black holes _are_ we talking about? Because it seems to me that the whole scare is due to a few people's not really understanding physics.
Gravity is actually the weakest force at a particle level. But ok, let's imagine a really really small gravity well.
Arguably the interesting thing about one would be, basically, "up to what distance can it gobble things up." In other words, the the Schwarzschild radius.
I'll use simplified version, which is: 3km for something weighing as much as our Sun, and it varies linearly with mass from there. Literally. For Something the size of Earth it would be 9mm, btw, but they won't collide particles weighing the same as _Earth_ there. If they did, I'd worry about _recoil_ before I worry about black holes.
So how big a black hole will they create there? Say, about the weight of two neutrons? _Three_ neutrons? Heck, let's be generous and smash a whole five neutrons together. Each neutron weighs 1.67492729x10^27 kg. So 5 of them is very approximately 8x10^-27 kg. The Sun weighs 1.9891×10^30 kg, let's say 2x10^30 kg.
So we get roughly 3km times 4x10^-57 km, or 4x10^-54 metres. That's the ridiculously infinitesimal size, up to which it could gobble matter. By comparison a helium atom has a radius of 31 picometres, or approx 3x10^-11 metres. Our black hole is about 10 to the 43'th power smaller than that. Write a zero, a dot, 42 more zeroes and a 1. That's how much smaller that black hole is than a helium atom.
To be absorbed by it, another particle would have to come that close to it, overcoming all other forces. Which become pretty damn strong when you try to get that close.
In effect, the _only_ way for that "black hole" to gobble any other particle, is for that other particle to be shot directly at it with an even bigger particle accelerator. With some incredible (and thanks to that guy Heisenberg, also pretty much impossible) accuracy. Otherwise, it will be bounced around by the other atoms, without ever getting close enough to one to actually absorb one and get bigger and meaner.
If that's the big threat to Earth, well, I've seen scarier kittens than that ;)
A polar bear is a cartesian bear after a coordinate transform.
The Tremendous Hadron Collider is more likely to create a black hole with the munchies.
Dewey, what part of this looks like authorities should be involved?