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Miscalculation Invalidates LHC Safety Assurances
KentuckyFC writes "In a truly frightening study, physicists at the University of Oxford have identified a massive miscalculation that makes the LHC safety assurances more or less invalid (abstract). The focus of their work is not the safety of particle accelerators per se but the chances of any particular scientific argument being wrong. 'If the probability estimate given by an argument is dwarfed by the chance that the argument itself is flawed, then the estimate is suspect,' say the team. That has serious implications for the LHC, which some people worry could generate black holes that will swallow the planet. Nobody at CERN has put a figure on the chances of the LHC destroying the planet. One study simply said: 'there is no risk of any significance whatsoever from such black holes.' The danger is that this thinking could be entirely flawed, but what are the chances of this? The Oxford team say that roughly one in a thousand scientific papers have to be withdrawn because of errors but generously suppose that in particle physics, the rate is one in 10,000."
This is voodoo science. And I don't mean the LHC experiments.
I mean the TFA that in essence claims that because an expert may be wrong, any probability the expert assigns to a risk can be ignored and inflated by as much you feel like it. Talk about bias.
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There is.
Matter being drawn into the black holes should be accelerated to damn close to the speed of light, and will emit massive amounts of gamma radiation, with a conversion rate that's higher than even fusion.
If we could harness the energy of the gamma emissions around artificial black holes, we'd be have vast energy generating capability, without the pesky fast neutrons that most fusion reactions generate.
I STILL don't think the LHC will kill us all but the fact we're debating it says something.
I don't know what you're trying to imply here.
People are still debating evolution.
Buckle your ROFL belt, we're in for some LOLs.
Opponent: Oh crap, you're whacking things together, it could destroy the earth, crazy scary technology we don't understand!
Proponent: That could never happen.
Opponent: OMG yes it could you don't know wtf you only have studied this shit your whole life you're not a sane normal rational person like the boys in Alabama!
Proponent: Look, we've done tons of calculations; we've compared this against real-world natural occurrences; we've considered the number of times the conditions we've come up with have occurred in our lifetimes, and it's huge. We're just scaling it down to a laboratory level so we can observe it in a controlled environment. It can't break anything.
Opponent: BUT YOU COULD BE WRONG!!!!
Support my political activism on Patreon.
My retirement fund is pretty much crushed at this point.
Being consumed by black holes created by a multibillion dollar scientific whiz-ma-gig is sounding like a pretty good exit plan.
I don't see the problem, facts:
1) We will all die some day.
2) The solar system will stop working some day.
So what's the problem? Sure it may kill us and all life on the planet, but does it really matter? We're screwed anyway.
LHC is used as an example, misleading headline written by Fox News. -1
~kulakovich
"Anyone Who Thinks the LHC Will Destroy the World is a Twat"
He's a particle physicist from my physics department (Manchester), and hence let it be known Oxford physicists are twats!
> I STILL don't think the LHC will kill us all but the fact we're debating it says something.
Yes, it says that people are easily scared by things they do not understand. See also: wireless, mobile phones, things that have a 'chemical' smell... Ask some random people what would happen if the sun were to be replaced instantaneously by a black hole with a mass equal to that of the sun (moving in the same direction as the sun with the same speed, etc). Most people will reply that the earth would get 'sucked' in the black hole... if you don't even understand gravity you have no place in a debate concerning the LHC.
Everyone is entitled to an _informed_ opinion.
paranoid person: The LHC is going to cause a black hole!
scientist: No, the LHC is not going to cause a black hole.
paranoid person: The chances of a scientist being wrong is 10%, therefore there is a 10% chance that the LHC will cause a black hole!
If you had super powers, would you use them for good, or for awesome?
Okay seriously?
The probability that Jimbo is wrong is unrelated to the probability of your tire failing. If jimbo says that you have a 1% chance of your tire failing, but there's a 50% chance that jimbo is wrong we can reach the following conclusion: There is a 50% chance that your tire has a 1% chance of failing. There is a 50% chance that your tire has some other probability of failing. Some other probability of failing includes values such as 0%, .5%, and 2%. It also includes a 100% probability of your tire failing.
However, we have to assume that Jim isn't pulling the 1% figure out of his ass. If your tire was 100% likely to fail, we can still assume that Jim based his statement on a reasonable analysis. Perhaps Jim didn't notice a nail in your tire, but without knowing the quality of Jim's inspection of your tire, or without having access information Jim doesn't have, it's hard to say that he has a 50% chance of being wrong.
Finally, in some cases a professional will include a certain amount of leeway in his figure. Chances are, Jim fully inspected the tire and doesn't see any reason why it would fail prematurely. Chances are, that 1% is left as wiggle room in case of invisible manufacturing defect or a mistake in his evaluation. In this case, Jim has already factored into his evaluation the chances that he's incorrect.
Who would remember if we all died?
The race of intelligent beings who, millions of years from now, finds a small black hole orbiting a star, with a flag on its moon.
Honestly, if the human race has to end, that is exactly how I want us to go out.
No, it's not a mistake. It all comes down to the fact that there are two general types of interpretations of probability:
Basically, you're treating this as an argument about probability in the first sense, when it is really about probability in the second sense. The argument is that even if your formulas lead you to asssign a degree of confidence of .00000000000001 to the proposition that the LHC will not destroy the Earth, that means very little if we assign a degree of confidence of .000001 to the proposition that you are wrong.
The point now, which other posters in this thread have made in other ways, is that the frequency model for probability theory is not relevant here, because this situation is not like a coin toss. For the situation to be like a coin toss, we would have had to do something like run the LHC a gazillion times, and observe how many of those times it ended up destroying the Earth. Therefore, the probabilities must be interpreted as degree of belief, and the number produced by any formula must be tossed out if the probability of getting the formula wrong is bigger than that number.
The assumption you're making here is that the number is the "probability of the event." Again, it is not; it is the degree of belief warranted to a specific proposition, given some other information.
Are you adequate?
It's both right and wrong. The conclusion that we can't trust the probability of disaster if we got it wrong is correct...bloody obvious, but correct. The part where they use the population of the Earth to determine whether the LHC "risk" is acceptable is frankly insane. This seems to suggest that if Bird flu wipes out half the population then the "risk" of running the LHC is suddenly now more acceptable?
As one of the authors of the paper in question, I'd like to point out that the headline and summary are very misleading. We have *not* identified any particular miscalculation and nor have we claimed to. Indeed, we are impressed by the recent safety report and agree that it is very unlikely that there will be a disaster.
The basic point of our paper is that what we really want to know is the chance of the disaster happening, but the reports give us the chance of it happening given a large number of physical assumptions. These probabilities are not the same, because there is a small but real chance that there is a flaw in these assumptions. This need not be due to any mistake on behalf of the physicists but may be like Lord Kelvin miscalculating the age of the Earth because nuclear fission and fusion were not yet known. Think of it this way: in a random sample of 1,000,000 cutting edge scientific articles that look as reliable as the LHC safety report, how many of them are likely to have flaws that invalidate their reasoning? This is especially pertinent as the safety report for the LHC's predecessor (the RHIC) failed to take into account anthropic considerations.
Of course even if the argument is flawed, we are still probably safe. We have indeed dealt with this point in the paper. The overall risk is very small, but larger than the raw calculations suggest, and non-negligible when there are 6.5 billion lives at stake. We thus urge caution and a reassessment of the safety of the LHC taking these considerations into account.
I encourage you all to read the actual article, which goes into many of these points in detail:
http://arxiv.org/pdf/0810.5515v1
I am sorry, The THEORY of evolution and the THEORY of creation both imply that I am somehow related to the people who make LOL cats and I just can not accept that. I CAN NOT accept that.
How many times can we roll the dice before our luck runs out?
Every single time. After that, there won't be any more dice to roll, or anyone to roll them if they did exist.
If we had some dice, we could roll them, if we existed.
Infuriate left and right