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Miscalculation Invalidates LHC Safety Assurances 684

Posted by timothy
from the philosophy-of-science dept.
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 The Oxford team say that roughly one in a thousand scientific papers have to be withdrawn because of errors but generously suppose that in particle physics, the rate is one in 10,000."
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Miscalculation Invalidates LHC Safety Assurances

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  • Voodoo Science (Score:5, Insightful)

    by alain94040 (785132) * on Wednesday January 28, 2009 @06:07PM (#26646369) Homepage

    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.

    --
    The 5 Steps to a Great Startup Idea [fairsoftware.net]

    • by madsenj37 (612413) on Wednesday January 28, 2009 @06:13PM (#26646455)
      If they are correct, what are the chances they are wrong (or right)?
      • "That isn't right" (Score:5, Interesting)

        by Jeremiah Cornelius (137) on Wednesday January 28, 2009 @06:20PM (#26646543) Homepage Journal

        "It isn't even wrong..." [wikipedia.org]

        What if they are so far off, that not only do they not produce black holes, they do nothing, but dim the lights in Switzerland?

        • by Anonymous Coward on Wednesday January 28, 2009 @08:04PM (#26647837)

          With all this uncertainty, it does however highlight two certainties.

          First, they have proved they can make mistakes. (While this should be obvious, it is however so often assumed that as they are the best of us, then they must know what they are doing).

          Second, it proves they do not know precisely what they are doing. (Again this should be obvious, (as there would be no point in building the LHC, if they knew precisely what was going to happen). But it again highlights how its assumed they do know what they are doing, when in fact they cannot know).

          This doesn't prove the LHC is dangerous, but it does prove they cannot prove the LHC isn't dangerous.

          At the same time, we have theories which can show possible dangers. Now possible doesn't mean probable, but it also doesn't mean impossible.

          Even the argument about atmospheric collisions is flawed, as the set of conditions inside the LHC is different to in the atmosphere. For example atmospheric collisions are very unlikely to have any chance of many Higgs Bosons in collision with each other whereas in the LHC it is possible, and thats just one example difference. Also we have no idea how multiple Higgs Bosons will behave or decay in groups or if it will allow them to interact or merge with other particles and how continuing collisions would affect them).

          I don't believe they would ever stop these experiments, as too many people involved with the science (and the money behind the LHC) have such intense desire to learn from the experiments. But I do at least hope, they use extreme caution and so only slowly, (over a period of a many months) move to (even currently possible) higher energy collision experiments, in very small increments. While its easy to assume they will, they have shown too many times how worried they are other experiment teams are going to get to the noble prize winning results first, so they do have extreme pressure on them, to rush into the higher energy experiments to show results fast).

          This is the only experiment in human history where we cannot learn from our mistakes. We have to be 100% certain it is safe, before each new step up is even attempted. (Too many mistakes have already been made and we have yet to even get into the more possible dangerous aspects of the experiments).

        • by Roger W Moore (538166) on Wednesday January 28, 2009 @08:33PM (#26648097) Journal
          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?
      • Re: (Score:3, Interesting)

        by goombah99 (560566)

        If they are correct, what are the chances they are wrong (or right)?

        They are precisely equal to:
        (1/1000)^N
        where N is number of indpendent studies agreeing with the conclusion and having no contraditory ones.

        For example, the ideas that the earth is round or that man evolved from apes or that smoking kills you is therefore not very well established since there are a lot of contradictory works that reduce that.

      • by BeardedChimp (1416531) on Wednesday January 28, 2009 @06:41PM (#26646873)
        Well if we want to find out who's right, we can just keep an eye on their webcam [cyriak.co.uk] for anything suspicious.
    • Re:Voodoo Science (Score:5, Insightful)

      by caffeinemessiah (918089) on Wednesday January 28, 2009 @06:22PM (#26646603) Journal

      This is voodoo science. And I don't mean the LHC experiments.

      It's not science, it's just probability. It's senseless to try to assess any statistical estimates *themselves* based on Physics, just the probability that they could be wrong based on some very broad assumptions. Specifically, any estimate is arrived at by a chain (rather, DAG) of logic. What you CAN estimate is the probability that any Physics-oriented estimate is based on incorrect assumptions, by (presumably) analyzing that chain of reasoning down to first principles and assuming that a "logic error" might have been made at any point. I hope that the authors aren't taking it further than this, in which case, this is statistical masturbation.

      • Re:Voodoo Science (Score:5, Insightful)

        by orclevegam (940336) on Wednesday January 28, 2009 @06:32PM (#26646737) Journal
        Essentially their argument boils down to because people make mistakes and we can calculate the odds of them making a mistake, if they calculate the odds of something and it's greater than the odds of them having made a mistake then you have to use the odds of them making a mistake as the probability of the event happening. Of course this reasoning is total bullshit, and just the sort of abuse statistics gets a bad name for. By that sort of reasoning we should all go play the lotto as clearly the odds of someone miscalculating the chances of winning the lottery are much better than the calculated odds of winning, never mind the fact that even if they made a mistake in calculating the odds it wouldn't shift the calculation enough either way to get it anywhere near the odds of them having made a mistake.
        • Re:Voodoo Science (Score:5, Insightful)

          by KagatoLNX (141673) <<ten.ajuos> <ta> <otagak>> on Wednesday January 28, 2009 @06:48PM (#26646969) Homepage

          Actually, this isn't that much voodoo.

          It's just saying that, if someone has a 1/10,000 chance of being wrong, their assurance that there is a 1/1,000,000,000 chance of something isn't that good of a bet. In other words, if you want the latter level of certainty, you don't really have it, because of the fallibility of the research itself.

          This is actually rather obvious. If Jimbo tells you that there's a 1% chance that your tire will go flat if you don't fix it, that's not 1% if Jimbo is wrong 50% of the time. At best, it's 50.5%. Or something like that.

          Assuming his brother Jethro is just as bad (but uncorrelated) with him, then their dual recommendation that it will go flat only gets you 25.25% certainty, not 1% (or 0.01%). The numbers may not be exactly right (my stats are rusty), but you get the point.

          Basically, they're saying that the research provides a wider error bound than it may claim, assuming that scientists uniformly make logical mistakes--which they very probably do.

          The implication, then, is that the LHC estimates should be independently done by other teams. This is, well, the basis of the scientific method, so essentially this study provides a statistical analysis of what we already know--after enough work, science gets results. Of course, the base theories assumed by all of the researchers could be wrong, which would be unfortunate, but the LHC is going to nail that one pretty quickly. :)

          This is not surprising, but not voodoo either.

          • Re:Voodoo Science (Score:4, Insightful)

            by orclevegam (940336) on Wednesday January 28, 2009 @07:18PM (#26647321) Journal
            To use your example, whether or not Jimbo is wrong 50% of the time does not make the odds 50.5%, as what your changing is the uncertainty, not the probability. Jimbos ability or lack thereof to calculate a probability has no impact on the actual outcome of the probability, just the likelihood that said probability is correct (or not). I'm sure the level of certainty in those calculations is already listed, and they might have a point if they tried to claim that the level of uncertainty for the calculations should factor in the probability that the paper(s) it's based on are incorrect, but the way the article is written (and the even more inflammatory summary) makes it sound like they are arguing that the calculated probability of the event should be changed.
            • Re:Voodoo Science (Score:5, Insightful)

              by Artraze (600366) on Wednesday January 28, 2009 @07:49PM (#26647683)

              If you took the ten seconds needed to read the abstract, you'd clearly see it's the former:

              "... If the probability estimate given by an argument is dwarfed by the chance that the argument itself is flawed, then the estimate is suspect. We develop this idea formally, explaining how it differs from the related distinctions of model and parameter uncertainty. Using the risk estimates from the Large Hadron Collider as a test case, we show how serious the problem can be when it comes to catastrophic risks and how best to address it."

              In other words, since the upper bounds of a catastrophic outcome is a least the probability that they were wrong, it's important to estimate the missing factor.

              Of course, the problem underlying this is the fact that if one _could_ calculate the missing factor, it wouldn't be an issue. In the case of the LHC, it is (probably :P) far more likely that the world would be destroyed by some yet-unknown physics (e.g. "the doctor" from Ender's Game) than by black holes. But, since it's impossible to predict the likelihood of something we don't know anything about, at some point one just has to throw the switch and see what happens.

              Bad journalism, solid (enough) science. As always...

              • Re: (Score:3, Interesting)

                by orclevegam (940336)

                If you took the ten seconds needed to read the abstract, you'd clearly see it's the former:

                ...

                Bad journalism, solid (enough) science. As always...

                My comments were based on the article and the summary rather than the abstract of the paper. Looking at the abstract it does appear to be an argument for formally factoring in something akin to a "chance we fucked something up somewhere" factor into the confidence of the prediction, with a particular emphasis on cases where the result of the event happening would be particularly bad.

                So, yes, as you put it, bad journalism, solid (enough) science. I still take issue with the article (and summary) as they pa

              • Re:Voodoo Science (Score:5, Insightful)

                by ppanon (16583) on Wednesday January 28, 2009 @10:33PM (#26649045) Homepage Journal
                Hmm. Well, the paper's argument is like saying that, if the average number of bugs (across all software and methodologies) in N lines of code is X, then somebody's claim that they have written a piece of software with M bugs in Y lines of code, where M/Y << N/X is bogus.

                This is patently ridiculous. If I write a relatively small piece of software where I have carried out a formal mathematical proof of the algorithms used in that software, I should obtain a much better bug ratio than the industry average, which includes work done by code monkeys working 90 hour work weeks.

                Put another way, it's not clear to me that the statistical results for papers where an error might mean a measured loss of academic status are relevant to papers where the analysis regards the possible destruction of the Earth. So far the sample size on the latter is pretty small but the ones that have predicted the absence of global life-ending catastrophe have been 100% accurate. Of course they would have to be or we wouldn't be around to speculate about it, so we can't really make a conclusion from that either. But the point is that the foundation of this paper's statistical argument is itself invalid.
              • Re: (Score:3, Insightful)

                by jandersen (462034)

                In other words, since the upper bounds of a catastrophic outcome is a least the probability that they were wrong

                It is not clear that this is the case. In fact: P(X)!=P(X|A)P(A)!+P(X|A)P(A) [from the actual article]. Your interpretation is only correct if the probablity that it goes is 100% if the assumptions are wrong.

          • by amRadioHed (463061) on Wednesday January 28, 2009 @07:22PM (#26647359)

            Yeah it is voodoo. If I calculate that there is a 1:10^20 chance an asteroid will destroy the earth this month, and someone else figures there is a 1:50 chance I am wrong, that does not make the odds of an asteroid destroying the earth 1:50. As wrong as the person calculating the odds are, the odds are still going to be incredibly small.

            If what you were saying was true we could destroy the earth by having a 10 year old do the calculations since they would almost certainly be wrong.

            • Re:Voodoo Science (Score:5, Insightful)

              by Anonymous Coward on Wednesday January 28, 2009 @07:56PM (#26647739)

              Actually the point the article makes is not that there is a 1/1000 chance that the LHC will destroy the world but rather it is meaningless to say that the odds are as small as they safety reports etc say because the chance of the reports being wrong is greater than their predictions.
               
                It basically boils down to saying that the scientists are saying there is a one in a billion chance that the LHC is dangerous then turning round and saying that there is a 1/1000 chance that that figure is wrong. Basically the point is that neither statistic is very helpful. Since the 2nd invalidates the first but tells you nothing about the actual probability of a dangerous event.

            • by maugle (1369813) on Wednesday January 28, 2009 @09:30PM (#26648567)

              I have calculated that there is almost no chance of money spontaneously raining out of the sky above me. However, I was drunk when I made those calculations, so they are most certainly wrong.

              *waits expectantly*

            • by mcrbids (148650) on Wednesday January 28, 2009 @11:43PM (#26649475) Journal

              Welcome to slashdot, where an insightful post such as yours is moderated up as funny...

          • Meaningless Math (Score:3, Insightful)

            by champion.p (1462707)
            Well... sort of. In fact, you make the same mistake that the authors appear to in your logic.

            If Jimbo tells you that there's a 1% chance that your tire will go flat if you don't fix it, that's not 1% if Jimbo is wrong 50% of the time. At best, it's 50.5%.

            But you assume that Jimbo's being wrong means that the probability of failure is 100%! It's not necessarily. In fact, Jimbo might be wrong in that the probability of a flat tire is actually 0% -- in which case, his being wrong has helped you. If this is the case, then the total probability is 0.5%, much better than 1%. This is the best case; 50.5% is the worst case, and neither is "more likely", because we don't kno

            • by Estanislao Martínez (203477) on Wednesday January 28, 2009 @08:16PM (#26647953) Homepage

              In fact, you make the same mistake that the authors appear to in your logic.

              No, it's not a mistake. It all comes down to the fact that there are two general types of interpretations of probability:

              1. The frequency at which one of the possible outcomes happens in repeated instances of an event of a specified type. For example, the probability of heads in a coin toss.
              2. The degree of belief that a cognitive agent assigns to a sentence. This degree of belief is related by the laws of probability to the degree of belief that an agent should assign to other sentences, in such a way that only some assignments are consistent (by a technical definition I won't go into here).

              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.

              It's this fallacious reasoning -- that if the theory is wrong, the probability of the event must be greater -- that make this article technically true, but useless.

              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.

          • Voodoo posting (Score:5, Insightful)

            by Burning1 (204959) on Wednesday January 28, 2009 @07:42PM (#26647597) Homepage

            This is actually rather obvious. If Jimbo tells you that there's a 1% chance that your tire will go flat if you don't fix it, that's not 1% if Jimbo is wrong 50% of the time. At best, it's 50.5%. Or something like that.

            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.

            • Re:Voodoo posting (Score:4, Informative)

              by sxeraverx (962068) on Wednesday January 28, 2009 @10:48PM (#26649119)
              That's not what he (she?) was saying. He was saying that if Jimbo says there's a 1% chance of the tire failing, and Jimbo's wrong 50% of the time (and that him being wrong is independent of the tire failing) and that we don't know what the chances of the tire failing are if he is wrong, then the maximum likelihood of the tire failing are at worst 50.5%. At worst.

              It could be as low as .5% to the best of our knowledge (if we know that whenever he's wrong, the tire never fails). But it can't be worse than 50.5%, because there's no way that the tire fails more than 100% of the time when he's wrong.

              Probability is not the same as maximum likelihood. Nor are either of them the same as knowing whether the event will actually happen or not. Probability is an estimate. Maximum likelihood is a worst-case estimate (in this case, where we define bad to be high probability). Knowing whether or not the thing actually happens is voodoo.
          • Re:Voodoo Science (Score:4, Insightful)

            by Roger W Moore (538166) on Wednesday January 28, 2009 @08:45PM (#26648205) Journal

            The implication, then, is that the LHC estimates should be independently done by other teams.

            But how can they be independent? They'll be basing their arguments on the same laws of physics which apparently only have a 1 in 10,000 chance of being right. The HUGE flaw in their assumption is that the probability of a paper being wrong is a flat 0.01%. It is not. Some papers use conservative, well established physics (such as the LHC safety report) others are pushing the boundaries. The LHC safety report uses the simple fact that we do not see planets and stars disappear into Black Holes to set a limit on any danger the LHC poses. Could there be a mistake in the calculation of the actual probability - yes there could. But it cannot be significantly different because we do not see stars and planets disappear!

        • Re:Voodoo Science (Score:5, Insightful)

          by IorDMUX (870522) <mark.zimmerman3NO@SPAMgmail.com> on Wednesday January 28, 2009 @07:09PM (#26647193) Homepage

          then you have to use the odds of them making a mistake as the probability of the event happening.

          This isn't what the actual study states, though the summary seems to hint that way. To quote from one-of-the-FA's:

          Which means we are left with the possibility that their argument is wrong which Ord reckons conservatively to be about 10^-4, meaning that out of a sample of 10,000 independent arguments of similar apparent merit, one would have a serious error.
          Of course, this doesn't mean that the LHC is dangerous, only that there is no reasonable assurance of safety which, as Mark Buchanan writing in New Scientist this week says, is not the same thing at all.

          To sum it up, they say that if a researcher predicts an occurrence rate for an event that is less than the researcher's own error rate, then the occurrence rate remains unknown ('cannot be assured')... not that it is equal to the researcher's error rate.

        • by CaptainPatent (1087643) on Wednesday January 28, 2009 @07:14PM (#26647267) Journal

          Essentially their argument boils down to because people make mistakes and we can calculate the odds of them making a mistake, if they calculate the odds of something and it's greater than the odds of them having made a mistake then you have to use the odds of them making a mistake as the probability of the event happening.

          Nuh-uh, that argument is solid and well formed.

          Hey, I have another "scientific" theory, 1 out of every 460 scientific papers are about artificial intelligence, That means the LHC is alive and we don't even know it yet.!

          • Re: (Score:3, Funny)

            by mh1997 (1065630)

            Hey, I have another "scientific" theory, 1 out of every 460 scientific papers are about artificial intelligence, That means the LHC is alive and we don't even know it yet.!

            You are wrong, it is not alive. It just emailed me and said that there was nothing to see here and keep moving along.

    • Re:Voodoo Science (Score:5, Insightful)

      by Bob-taro (996889) on Wednesday January 28, 2009 @06:27PM (#26646669)

      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.

      Bias? Hype, maybe. Actually, this does make some sense, IMO. Say I was offering to shoot an apple off the top of your head and I told you I'd calculated there was only a 1 in 1 million chance of the bullet hitting you instead. Now if you knew (somehow) that there was a 1 in 10 chance I'd gotten the calculation wrong, you're going to look at it as more of a 1 in 10 chance of getting hit ... or at least way more than one in 1 million.

    • Re:Voodoo Science (Score:5, Insightful)

      by bhagwad (1426855) on Wednesday January 28, 2009 @06:39PM (#26646837) Homepage
      I agree. Just look at this statement: "The focus of their work is not the safety of particle accelerators per se but the chances of any particular scientific argument being wrong." Can you get any broader than that? What they're essentially saying is that anything can be wrong - Including their own paper.
    • Re: (Score:3, Insightful)

      by WarJolt (990309)

      Particle collisions happen in nature.
      If we could that easily blink ourselves out of existence then we'd see planets disappearing all the time and black holes would be everywhere.

    • Re: (Score:3, Insightful)

      by yancey (136972)

      Isn't this exactly the sort of physics that the LHC machine was designed to investigate? Higgs boson and particle mass, to be sure. That's what we always hear about, but it's more than that. The LHC will be brought up to full power gradually, over a series of incremental tests and experiments, over months and years, looking for anything unusual in the data, something we haven't anticipated. The data from those experiments can be examined for signs of black hole formation. If they do appear anywhere below LH

  • by QuantumG (50515) * <qg@biodome.org> on Wednesday January 28, 2009 @06:09PM (#26646399) Homepage Journal

    Maybe I just like Romulans, but when I hear that the LHC will be making black holes I don't think about "woo, the earth is gunna get swallowed!" I wonder if there are any cool ways to use them for power generation.

    • by TheMeuge (645043) on Wednesday January 28, 2009 @06:13PM (#26646439)

      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.

      • by setagllib (753300) on Wednesday January 28, 2009 @06:19PM (#26646531)

        Great. Now in a matter of years we'll have hippies protesting abuse of Nature's Own Black Holes for generating power. It's not really sustainable energy if all the mass you add to the hole extends its event horizon. (Does it?)

    • Re: (Score:3, Funny)

      by Chabo (880571)

      The real problems come in when aliens from outside our space-time continuum try to harvest their young in your warp core, thinking it's a natural gravity well! Time starts doing some whacky stuff!

    • Re: (Score:3, Interesting)

      by WindBourne (631190)
      Getting rid of our nuclear "waste" (which disregards the potential to use it for something useful, like an IFR)? Of course, I wonder if you feed it, will it grow and stay around? And suppose you do feed it, how does it collapse on itself and what happens to the matter that was feed it? Personally, I think this would be a REALLY cool experiment to do in about 50 years outside of the solar system.
  • by Reapman (740286) on Wednesday January 28, 2009 @06:16PM (#26646485)

    My first thought from reading the summary is that essentially we're at a point in technology or whatever that we could, POSSIBLY, destroy the planet in a literal sense. That's a scary thought, especially if you think what we'll be capable in a hundred years from now.

    I STILL don't think the LHC will kill us all but the fact we're debating it says something.

    • by Xtravar (725372) on Wednesday January 28, 2009 @06:25PM (#26646637) Homepage Journal

      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.

    • by Thiez (1281866) on Wednesday January 28, 2009 @06:45PM (#26646929)

      > 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.

  • by Amazing Quantum Man (458715) on Wednesday January 28, 2009 @06:17PM (#26646499) Homepage

    From last Sunday [userfriendly.org]

  • by zappepcs (820751) on Wednesday January 28, 2009 @06:20PM (#26646547) Journal

    The purpose of the LHC is noble, and results could be what we need to get off this rock and really dominate the galaxy. If they destroy the Earth... meh, it was a good try. Maybe next time.

    • Re: (Score:3, Funny)

      by Krater76 (810350)
      Maybe that's why we haven't met any aliens. The alien societies all get to the point where they develop their versions of the LHC and annihilate themselves due to an underestimation of the consequences.
  • by Werthless5 (1116649) on Wednesday January 28, 2009 @06:22PM (#26646579)

    Means that there is a much greater than zero probability? Sorry, either the paper is wrong or your interpretation of it is wrong. Publishing a probability is not a determination of that probability.

    There is no published figure regarding the probability of your computer turning into chocolate pudding before it reaches warranty. The probability is still approximately zero despite that.

    The probability of a black hole at the LHC swallowing the Earth is approximately zero, and it doesn't matter how many sensationalist journalists try to misconstrue real science in an effort to drum up sales.

  • by squoozer (730327) on Wednesday January 28, 2009 @06:22PM (#26646587)

    and I don't think it's the assurance that the LHC won't produce black holes that swallow the earth. There reason the whole LHC black hole rubbish is dismissed out of hand is simply because we have already obvesrved particles colliding with much higher energies than the LHC can produce and they didn't form black holes. Where did we observe these collions - in earth atmosphere. We built the LHC so that we could study the collisions in a controlled manner not because they are of particularl high energy.

  • by bluefoxlucid (723572) on Wednesday January 28, 2009 @06:25PM (#26646641) Journal

    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!!!!

  • by Sponge Bath (413667) on Wednesday January 28, 2009 @06:29PM (#26646697)

    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.

  • LHC is used as an example, misleading headline written by Fox News. -1

    ~kulakovich
  • by WindBourne (631190) on Wednesday January 28, 2009 @06:35PM (#26646775) Journal
    That this would be the end of the world that neo-cons hope and pray for. Now, they will not have to see a black president in for long, nor take responsibility for their actions.
  • by BeardedChimp (1416531) on Wednesday January 28, 2009 @06:36PM (#26646787)
    "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!
    • Re: (Score:3, Informative)

      by Roger W Moore (538166)
      These were Oxford statisticians, not physicists. The physics department is actually extremely good...but not as good as Cambridge's :-)
  • by dangitman (862676) on Wednesday January 28, 2009 @06:36PM (#26646789)

    'If the probability estimate given by an argument is dwarfed by the chance that the argument itself is flawed, then the estimate is suspect,'

    But if the improbability is large enough, and you hook it up to a nice, hot cup of tea; then we'll travel instantaneously through every point of the Universe, and possibly create a worried-looking whale and a bowl of petunias.

  • Sensationalist BS (Score:5, Insightful)

    by ceoyoyo (59147) on Wednesday January 28, 2009 @06:46PM (#26646939)

    The article is a pile of BS topped by a sensationalist (and completely wrong) headline. The paper abstract is interesting, but that's it.

    Essentially the blog article makes the jump from 1 in 1000 papers being withdrawn because of "an error", any error, to the idea that the safety of the LHC is "invalid" due to a "massive miscalculation."

    How can a hypothetical miscalculation be "massive?" Anyway, you can't just take an average retraction rate for papers and assume it applies to anything you like. The arguments for the LHC being safe are based on well established science. That is, for the LHC to destroy the world not only would ONE paper have to be wrong, but a LOT of papers would have to be wrong, and all in the same direction.

  • by DrVomact (726065) on Wednesday January 28, 2009 @07:03PM (#26647131) Journal

    If the probability estimate given by an argument is dwarfed by the chance that the argument itself is flawed, then the estimate is suspect.

    The headline says "Miscalculation Invalidates LHC Safety Assurances", yet the quote from the abstract seems to say that because arguments are sometimes "flawed" (terribly squishy word, that), it follows that for crucially important calculations we have to...well, the abstract doesn't say what we should do, and there's no link to the actual article. (Maybe there's a good reason for the latter.)

    This amounts to the assertion that if an estimate is about something very important, then we can't trust the estimate, because some estimates are mistaken. In other words, we can't make estimates about important things—just trivial ones.

    Unless someone produces the article in question, and unless it actually makes a more substantial argument than I quoted, I vote this a waste of my time on the part of whoever submitted it. May the rats eat your mail.

  • Of course (Score:5, Interesting)

    by Nerull (586485) <`ten.sdt' `ta' `lluren'> on Wednesday January 28, 2009 @07:14PM (#26647281)

    The the safety of the LHC does not depend on a single calculation.

    For a black hole created by the LHC to destroy the earth essentially requires everything we know about physics to be wrong.

    First, can it even create them? The Standard Model says no - not even close. A certain category of String Theory models say maybe. This same models predict that these black holes are everywhere, being created all the time, even here on Earth.

    Will black holes evaporate? They certainly should. If we are wrong about this than in all probability we are wrong about being able to create them at all as well - and we should hope we are, since they'd have swallowed up the universe by now if they were dangerous.

    Is a stable micro black hole even dangerous? The numbers I've seen show a black hole like this would behave more or less like a neutrino. Maybe hitting an atom every few thousand or million years. The sun will enter its red giant stage, destroy Earth, and shrink down to a white dwarf before the black hole gains any significant mass. I don't think we will care much at that point.

  • awesome logic (Score:5, Insightful)

    by j0nb0y (107699) <jonboy300@yahMOSCOWoo.com minus city> on Wednesday January 28, 2009 @07:15PM (#26647285) Homepage

    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!

  • False claim (Score:4, Informative)

    by Grayputer (618389) on Wednesday January 28, 2009 @07:38PM (#26647529)

    The LHC paper has been 'published'. It has been peer reviewed up the butt. It has not been withdrawn. It obviously then falls into the 'other' 999/1000. Like slashdot is fond of saying: there is nothing to see here, move along.

  • by vyrus128 (747164) <gwillen@nerdnet.org> on Wednesday January 28, 2009 @07:39PM (#26647557) Homepage

    Seriously, nothing to see here. This is truly an embarrassment to Slashdot (if that's even possible). Just move along.

  • Why I'm not worried (Score:5, Informative)

    by KokorHekkus (986906) on Wednesday January 28, 2009 @07:42PM (#26647603)
    The LHC (http://en.wikipedia.org/wiki/Lhc [wikipedia.org]) has a collison energy of in the TeV scale (tera = 10^12)

    The Pierre Auger Observatory (http://www.auger.org/observatory/ [auger.org]) records one 10^19 eV hit per km^2 a year, just on earth. If that hasn't turned up any major anomalies in our solar system or even in the major mass centers in our close vicinity over the billions of years it's been happening then I would like an explantion why.
  • Every day.... (Score:5, Informative)

    by bjorniac (836863) on Wednesday January 28, 2009 @07:43PM (#26647617)

    Every single day the earth is bombarded with particles of far higher energy than those the LHC could ever come close to producing. We've observed cosmic rays with energies that are several orders of magnitude higher than the LHC can ever come close to producing. The Pierre-Auger project will probably reveal that we're hit by far more of them, and might even tell us where they're coming from. So if the LHC were capable of producing a world ending event, we already wouldn't be here. Sure, "scientists meddle with forces they don't understand" sells papers, (and let's face it, if we DID understand them, we wouldn't need to meddle) but we all do that. How many of you know exactly how the computer sitting on your desk works, down to the excitation states of silicon? Yet you still use them and don't worry about them causing the world to end, because you know that it just isn't possible. The same analysis works for the LHC.

  • The real risk (Score:4, Insightful)

    by TopSpin (753) * on Wednesday January 28, 2009 @07:48PM (#26647657) Journal

    If CERN leaves the window open long enough by failing to produce real collisions in the LHC that don't destroy the planet the alarmists WILL achieve their goals and get it shut down. Have no doubt. Politicians of all stripes thrive on alarmist nonsense. This 'story' is exactly the sort of double-speak that can lend just enough credibility to the alarmist argument to get the ball rolling.

  • Clarifications (Score:5, Informative)

    by Toby_Ord (1463921) on Wednesday January 28, 2009 @08:35PM (#26648121)

    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 [arxiv.org]

    • Re:Clarifications (Score:4, Interesting)

      by kwikrick (755625) on Thursday January 29, 2009 @07:03AM (#26651669) Homepage Journal

      Okay, I've read the paper. I do not agree with it.

      You claim that when a probability estimate for some event is very small, much smaller than the chance of the estimate being flawed, then we should consider the actual probability of the event to be larger.

      In the papers terminology:

      P(X) = P(X|A)P(A) + P(X|not A)P(not A)

      Where given are:

      - P(X|A) the probability estimate based on some argument and

      - P(A) the chance that the argument is flawed

      You then argue that if P(X|A) is very small, then P(X|not A), an arbitrary number, is probably much larger, and therefore P(X|not A) P(not A) may be significant compared to P(X|A)P(A). Thus, you argue, P(X) is probably higher than P(X|A).

      This is where you go wrong.

      You basically insert an arbitrary number, P(X|not A), based on an inexpert opinion, in the equation. Sure, the maths add up, you get a higher value for probability of the event, but your new probability estimate is no longer based on expert knowledge. You use some small number (1/1000) for P(X|not A) in your examples, but this makes no sense. Why not assume 50/50 if you simply don't know how likely it is that some event will happen? The main component of your new probability estimate is now only the statistical probability of an expert being wrong, which is independent of the probability of some event taking place.

      In other words: you simply replace the estimate of an expert with the estimate of a lay person, multiplied by the change that the expert is wrong. However, even if the expert is wrong, that does not mean the lay person is right. The number you end up with is junk, it is meaningless. It should definitely not be used for risk assessment.

      This is very dangerous use of probability theory. The argument in your paper is easy to follow, but it is false, and seeing that is not so simple. I sure hope no policy maker will read your paper and base important decisions on it.

  • by Alomex (148003) on Thursday January 29, 2009 @05:55AM (#26651319) Homepage

    The headline and summary are misleading but the main point of the paper stands. Once we are talking about probabilities of one-in-a-million or less, other second order terms come into effect.

    Example: the probability of the blood "not being from OJ Simpson" was declared to be "one-in-six-billion". Well at those orders of magnitude the probability of an unknown-to-him twin brother are higher than that. Of course I'm not claiming he has one. In all likelihood he doesn't, it's just that the probability of that event is around 1-in-100 million, which far outweighs the 1-in-6,000,000,000 given by the genetics "expert".

    So the correct thing to say is that the chances of the blood not being OJs is one-in-100,000,000. Good enough for me to convict and scientifically accurate. The other figure is nonsense.

Statistics are no substitute for judgement. -- Henry Clay

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