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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 The Oxford team say that roughly one in a thousand scientific papers have to be withdrawn because of errors but generously suppose that in particle physics, the rate is one in 10,000."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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It's not like they actually showed an error in the calculations or showed any proof of danger.
This is a bunch of bored brains saying that on the basis of pure statistics: If one in 10,000 papers have an error in them then the probability of this paper having an error in it is 1 in 10,000 ergo any claim must be degraded by 10^-4?
They should be spending their valuable time actually checking the facts and figures and coming up with some real conclusions not some abstract theory on the reliability of scientific calculations..
Either they are right (the LHC is safe), and nothing happens. Or they are wrong, and no one is left to say anything about them being wrong.... ;-)
Looking for any old 8-bit Heathkit/Zenith software/hardware - http://heathkit.garlanger.com
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.
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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.
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!!!!
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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.
People are. Nobody who actually knows something about the subject is debating evolution.
> 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.
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.
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?
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 know what the conditional probabilities are. 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. We cannot handpick these probabilities. From the TFA (not the abstract):
The other unknown term in equation (1), P(X|not A) [read: the probability of the catastrophe given we're wrong], is generally even more difficult to evaluate, but lets suppose that in the current example, we think it highly unlikely that the event will occur even if the argument is not sound, and that we also treat this probability as one in a thousand.
(emphasis and comment mine). I disagree. This probability is impossible to evaluate, and so this paper means nothing.
Seriously, nothing to see here. This is truly an embarrassment to Slashdot (if that's even possible). Just move along.
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.
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.
Lurking at the bottom of the gravity well, getting old
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).
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?
Their whole study is voodoo. This isn't physics, it's just math. Simple math doesn't have grey areas.
The maximum output for the LHC is in the 10^15eV range. That's the same as many cosmic rays. In fact, the rate of cosmic ray impact at about 10^15eV is about one impact, per square meter of the Earth's surface, per year.
The Earth's surface area is 5.10227658 × 10^14 meters. We can assume cosmic rays have been pouring in at roughly the same rate for about 4.6 billion years, or the age of the Earth.
That means, we have not seen a "Earth Ending Event" in 2.34704723 × 10^24 chances. And that ignores that there's a large portion of cosmic rays that come in with an energy GREATER THAN 10^15eV.
There's no gray area here. Even assuming that we've gotten incredibly lucky and the very next cosmic ray impact on the Earth will cause a black hole, ... oops, not that one, no the next one, oh wait (never mind)... The odds of any single collision causing a black hole event would be at best in the range of 1:1x10^24. That's not one in a hundred billion, that's:
1 : 1,000,000,000,000,000,000,000,000
That's one in a septillion. That's close to the number of stars in the visible universe. This whole thing is nothing but a ridiculous anti-science rant.
Life, the Universe, and Everything... in my image.
A black hole CAN NOT BE CREATED By US!!! Even if several thousand atome worth of matter were smashed together into an area one millionth of an atomic nucleus, one thousand atoms worth of gravity doesn't amount to anything in the scale of the real world. even if these atoms stayed in that configuration for many seconds or minutes, they still don't have enough mass to create gravity that could start pulling in other matter, especially since the collisions are set-up in a very high vacume and all the surrounding matter (sensors etc.) are bolted very tightly to a very sturdy base. The fact that people continue to debate this issue just astounds me. A tiny bit of concentrated matter is still only a tiny bit of matter, no matter how much you consentrate it! Remember, a true black hole has the mass of a star in an area the size of a single atomic nucleus, so that's some pretty consentrated mass. You can hang a lead ball on a 2000 foot string next to a granite mountain face and only barely detect the deflection of the ball on the string. Gravity is a very weak force people.
Keep passing the open windows...
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?
Who would remember if we all died?
At the end of days, at the end of time.
When the Sun burns out will any of this matter.
Who will be there to remember who we were?
Who will be there to know that any of this had meaning for us?
And in retrospect I'll say we've done no wrong.
Who are we to judge what is right and what has purpose for us?
With designs upon ourselves to do no wrong,
running wild unaware of what might come of us.
The Sun was born, so it shall die, so only shadows comfort me.
I know in darkness I will find you giving up inside like me.
Each day shall end as it begins and though you're far away from me
I know in darkness I will find you giving up inside like me
Without a thought I will see everything eternal,
forget that once we were just dust from heavens fire.
As we were forged we shall return, perhaps some day.
I will remember you and wonder who we were.
"Honestly, if the human race has to end, that is exactly how I want us to go out."
You or a handful of individuals anywhere don't get to choose that. It's unspeakably arrogant to even hold a fleeting thought that you do, and the real world and people in it otherwise known as the human race will smack you down the moment you attempt to apply it to real life.
And it's for that very reason that large projects like the LHC come up against so much opposition. Fear of the unknown fueled by arrogant, juvenile, man-children spouting utter garbage like the above and reaffirming to the average man on the street the belief that the 'scientific community' is very much a separate group of crazies that can't be trusted to not kill everyone. Funnily the (majority) of scientists themselves are not the ones who talk this sort of rubbish, it's the hanger-ons, the zealots and the fanboys. But to the wider community it appears the same. In this thread alone at the moment it's about 50/50 scientific arguments vs rubbish like this.
If you don't care about your own life that's fine. But don't expect the average man on the street to ever accept the risk of death to themselves and families for your particular cause.
Basically all the arguments for black hole creation fail when you ask the question, "Where are you going to get all the mass to create the black hole?"
A black hole has much more mass than our planet. Energy released from the destruction of mass is supposed to be very large; even if it were possible to convert energy into mass at the LHC, the mass gain should be negligible.
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.
"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."
How can you conclude this? You state that there is a chance that this calculation is flawed. Well..that's obvious.
The probability of an estimate being flawed says exactly nothing about what the correct estimate should be.
Indeed, the error in the estimate could go either way. It could even be that the chances are in fact even smaller.
The reality is, however, that to all probability the calculation is correct.
You state that you "really want to know what the chance of the disaster happening [is]". Well in that case: look at the calculations and see if any flaws can be found instead of generalizing about "a probability of any scientific study being flawed".
Any ways, if you really are interested in that probability, the factors that influence this probability should be studied: amount of reviews, type of study, qualifications of the authors etc. That would give you a model for judging the real chance of mistakes for this particular study.
Further you would have to find a link between the flaws and the amount at which the results are wrong, so you could estimate the chance that this particular study could be so incredibly wrong that there is a reasonable chance they overlooked a factor that would make the disaster happening a real possibility.