Exploring the Risks of the Large Hadron Collider

[Almanzo]

If you do an experiment which runs a one in a million risk of killing billions of people, would this be morally equivalent to doing an experiment which will surely kill thousands of people?

 

[ZapperZ]

If you do an experiment which runs a one in a million risk of killing billions of people, would this be morally equivalent to doing an experiment which will surely kill thousands of people?

Where did such a probability come from, and why is it relevant in this thread?

Zz.

 

[humanino]

If you do an experiment which runs a one in an million risk of killing billions of people, would this be morally equivalent to doing an experiment which will surely kill thousands of people?

This question is so lame...
This is a forum for physics discussion, so please define "morally equivalent".
Please specify also the role of pain felt by people in your experiment.

The fact is, there is always a probability to destroy the Earth when you do anything. And there are relevant probabilities to the destruction of human and animal species and/or the entire Earth, like political ones, which belong somewhere else.

edit
collision with Zz answer. I hope that will not blow up my computer !

 

[Questman]

I am very dissapointed in how much affect the BH story has had on the LHC. cohorts of people I know, including family and friends, keeping assuring me that we must not start up the LHC because it will kill us all.

Very, very dissapointing.

 

[humanino]

Very, very dissapointing.

That's very, very true, seriously, there is so much more to discuss about the LHC. It is a wonderful tool. Unfortunatly, CERN PR might be too young, or too scientific, to communicate efficiently (unless there is really no way to communicate properly this level of science, which I don't believe). By "too young" I mean that they might not have put enough control on which is the right "emphasis".

 

[Vanadium 50]

Do you know what's going to happen, EXACTLY!

When you try a new recipe in your kitchen, do you know what will happen EXACTLY?

Are you nevertheless certain it won't destroy the earth?

 

[Vanadium 50]

Unfortunatly, CERN PR might be too young, or too scientific, to communicate efficiently

How does any PR organization counter the argument "I haven't read what you wrote concerning safety, and don't intend to, but I am sure it's wrong and what you are doing is dangerous."?

 

[Haelfix]

This is so ridiculous. The Earth gobbling bh bit is a fairytale that has safely been falsified. You wouldn't see anywhere near the stellar abundances that we do in galaxies. Stars are bombarded by high energy cosmic rays, and you'd expect to see a lot more black holes than we do if the scenario held water. You'd also see a lot more patterns in the sky. For instance if you're close to a pulsar, you'd expect there to be a lot of statistical voids and departures from homogeniety as stars in the vicinity would have a lot more inverse barns worth of collisions to deal with.

 

[atyy]

Physicists know what they are doing, and the LHC will not destroy the Earth.

It is a very hard question. I would advise you to read Randall's papers, or lectures.
Warped Extra-Dimensional Opportunities and Signatures

If physicists know what they are doing as stated in the first quote, then how could there be a lack of knowledge about estimates for black hole production as stated in the second quote?

That's very, very true, seriously, there is so much more to discuss about the LHC. It is a wonderful tool.

Why not treat the public respectfully and admit that one doesn't know if the LHC will destroy the earth. Then say, on the basis of such and such a theory, that is tested to such and such accuracy in such and such a regime, such and such a bound has been put on it. But the theory has not been tested in such and such a region so we don't know if the bounds are good in those regions. Less "PR" perhaps, and more science? And I find it against the spirit of curiosity to say to the public: you shouldn't be interested in this, you should be interested in that. I had never heard about black holes and the LHC until I came across this thread (the "PR" I got was something about a Higgs boson). After reading this thread, I am not reassured about the black holes. But I am reassured that CERN's PR is not this thread!

 

[Almanzo]

In the interest of the survival of mankind, some early warning signs could be established, which should result in the discontinuation of the experiment, followed by an international endeavour to start a colony on Mars. (Early discontinuation of the experiment would leave more time to start such a colony. It could be done in 200 years, but not in 200 weeks.)

Early warning signs would include:

-- damage to the Geneva installation itself or to adjacent buildings
-- ocean-going ships springing tiny leaks
-- people around the Dead Sea and other low lying regions receiving line-shaped lesions
-- changes in seismic activity, such as deep, tiny earthquakes

 

[ZapperZ]

If physicists know what they are doing as stated in the first quote, then how could there be a lack of knowledge about estimates for black hole production as stated in the second quote?

Why not treat the public respectfully and admit that one doesn't know if the LHC will destroy the earth. Then say, on the basis of such and such a theory, that is tested to such and such accuracy in such and such a regime, such and such a bound has been put on it. But the theory has not been tested in such and such a region so we don't know if the bounds are good in those regions. Less "PR" perhaps, and more science? And I find it against the spirit of curiosity to say to the public: you shouldn't be interested in this, you should be interested in that. I had never heard about black holes and the LHC until I came across this thread (the "PR" I got was something about a Higgs boson). After reading this thread, I am not reassured about the black holes. But I am reassured that CERN's PR is not this thread!

Respect comes in both direction. The FACT that CERN (and BNL) actually did an extensive safety review showed that both institutions respect the need of the public to be reassured of the safety of these machines. Now, the public, on the other hand, also need to show respect to these scientists in the sense that they know at least MORE than most in what they do based on our current understanding. While there are many things we don't know, there are also many things that we do know. That is how we are able to design new experiments and look for new things.

Again, we have seen many higher-energy particle collision elsewhere in our universe. The Auger Observatory measurements from AGNs, for example, are detecting particles with energies several orders of magnitude higher than what the LHC can ever dream of getting. This implies that not only are there particles of significantly higher energies, but also that when these particles collide, they do not produce any black hole to swallow anything. The RHIC safety analysis report clearly indicated this by mentioning the fact that the moon is still there!

So respect in this case means that one simply does not challenge something based on ignorance. It shows the lack of respect to put some effort into knowing what one is objecting to.

Zz.

 

[buffordboy23]

I wonder if the book "Angels and Demons" by Dan Brown has inspired any of these concerns. If you haven't read the book, the author creates a very "fictitious" picture by developing the story around the LHC at Cern, where a large amount of antimatter is used to build a very destructive bomb, and mixing the ethics of science and religion. I spoke with at least one person that took his story very seriously in its application to the real world. =(

The probability of the Earth being destroyed by an impact of a massive asteroid or by a nuclear holocaust is significantly more probable by many orders of magnitude than the BH supposition. From what I saw, it is very questionable that black holes will be created at LHC. If they are, they are likely to dissipate to nothing via Hawking radiation, if the theory is correct; should the theory be incorrect, the BH is so small that it would require a time longer than the age of the universe to engulf the earth. Moreover, the high velocities of the colliding particles (near the speed of light) will likely send any BHs out of the gravitational influence of the Earth, unless their velocity is less than Earth's escape velocity by a very small chance. The sun will die in less than five billion years from now, so this should be the larger (but still negligible) concern.

 

[ZapperZ]

I think it was LEP, not LHC, no?

Zz.

 

[buffordboy23]

I am pretty certain that it is the LHC. I actually listened to the audio book on a long road trip, and I distinctly remember the prologue and its long discussion of the LHC. I found this interesting link that is a CERN spotlight FAQ inspired by Angels and Demons:

http://public.web.cern.ch/Public/en/Spotlight/SpotlightAandD-en.html

 

[ZapperZ]

I am pretty certain that it is the LHC. I actually listened to the audio book on a long road trip, and I distinctly remember the prologue and its long discussion of the LHC. I found this interesting link that is a CERN spotlight FAQ inspired by Angels and Demons:

http://public.web.cern.ch/Public/en/Spotlight/SpotlightAandD-en.html

Ah, thanks. It has been ages since I read the book.

Zz.

 

[atyy]

Respect comes in both direction. The FACT that CERN (and BNL) actually did an extensive safety review showed that both institutions respect the need of the public to be reassured of the safety of these machines. Now, the public, on the other hand, also need to show respect to these scientists in the sense that they know at least MORE than most in what they do based on our current understanding. While there are many things we don't know, there are also many things that we do know. That is how we are able to design new experiments and look for new things.

Again, we have seen many higher-energy particle collision elsewhere in our universe. The Auger Observatory measurements from AGNs, for example, are detecting particles with energies several orders of magnitude higher than what the LHC can ever dream of getting. This implies that not only are there particles of significantly higher energies, but also that when these particles collide, they do not produce any black hole to swallow anything. The RHIC safety analysis report clearly indicated this by mentioning the fact that the moon is still there!

So respect in this case means that one simply does not challenge something based on ignorance. It shows the lack of respect to put some effort into knowing what one is objecting to.

Zz.

I think one thing to keep in mind is that even in the scientific community controversies go on long after the "objective" evidence exists to establish a certain view. (Unless you never had a paper rejected by a "clueless" referee or editor?) But I presume most referees are being honest and conscientious, and so we treat them with respect (my "public" stance, not necessarily what I really think;)

Anyway, I agree in general with your post. That's why I distinguished between CERN and particular posts on this thread that claim to represent the interests of CERN (Also, the tenor of discussion started quite differently on the 2 threads which were merged).

 

[Peaceful]

Big bangs, Black holes and Higgs bosson oh my

I heard about these mini black holes that might be created inside the LHC. People are freaking out and say it's going suck us in and destroy the world. But wouldn't a mini black hole with a small mass and tiny schwarschild radius evaporate into hawking radiation.

Could recreating the Big Bang in the LHC destroy the world(don't really know much about the big bang thing)? What if a previous civilization created our universe in a similar experiment.
:P weird

 

[ZapperZ]

Again, as a reminder, any thread or post anywhere on PF related to the issue of "LHC" "LHC black hole" etc. will be merged into this thread. We also hope that posters who didn't see this thread will make an effort to read it from the beginning once they see their threads were merged here, because this thread has addressed the issues surrounding this topic.

Zz.

 

[james77]

When you try a new recipe in your kitchen, do you know what will happen EXACTLY?

Are you nevertheless certain it won't destroy the earth?

A recipe is generally a tried and tested formula of sorts, i.e. I have a good idea of what the outcomes are going to be based within certain parameters. For example with scrambled eggs there's generally two extreme outcomes at each end of the spectrum i.e. there're either too watery or too thick, but within these levels there's a whole array of possible good outcomes, depending upon your tastes of course. With a recipe one can be exact within a relative range and I don't think this is exactly the same as an experiment that has no previous measurements that were done under comparable conditions before. I would be like heating up the scrambled eggs using a completely new method of heating i.e. conventional vs. microwave; obviously this will seriously affect the outcome.


<Are you nevertheless certain it won't destroy the earth? > Well, you've never been to my kitchen at dinner time!

 

[jms5631]

But we are very familiar with the fundamentals involved in physics going on at LHC. Certainly, we can't predict with any certainty if we'll find the Higgs boson, or supersymmetry for example, but that doesn't mean that we are not familiar enough with the fundamentals of high energy particle collisions to be able to ascertain their safety. There is a wide chasm between having such a comprehensive degree of knowledge that it gives us a small menu of allowed outcomes to an experiment, and having enough knowledge based on both established theory and observation to certify its safety. We may not know enough(arguably, but barely so) to satisfy the first condition, but we certainly have enough theoretical and observational evdience to satisfy the second. We are familiar with high energy physics, and as vanesch pointed out earlier in this thread, the biggest leap has already been taken. There is not a rational or cogent argument that I've seen, based on scientific theory or risk assessment, that stands up to scientific scrutiny. No argument has been presented that shows based on our current level of knowledge, or due to our ignorance, that any threat worth noting stands.

 

[james77]

Again, we have seen many higher-energy particle collision elsewhere in our universe. The Auger Observatory measurements from AGNs, for example, are detecting particles with energies several orders of magnitude higher than what the LHC can ever dream of getting. This implies that not only are there particles of significantly higher energies, but also that when these particles collide, they do not produce any black hole to swallow anything. The RHIC safety analysis report clearly indicated this by mentioning the fact that the moon is still there!

Again, this is a reasonable observation. However it's possible that the reason why MBHs don't form in the high outer atmosphere maybe due to a case of matter starvation, there's literally no way for them to get going out there. Also I don't think anyone knows for sure exactly how the Earth's natural electromagnetic field functions in these collisions and I'm not sure that comparing it with the LHC at CERN is really the same thing.

 

[atyy]

<Are you nevertheless certain it won't destroy the earth? > Well, you've never been to my kitchen at dinner time!

The RHIC safety analysis report clearly indicated this by mentioning the fact that the moon is still there!

Deary me, I seem to remember from basic quantum mechanics that the moon is not necessarily there unless we look! I'm not looking at the moon at the moment. I hope it is not presently in your kitchen.

 

[james77]

Deary me, I seem to remember from basic quantum mechanics that the moon is not necessarily there unless we look! I'm not looking at the moon at the moment. I hope it is not presently in your kitchen.[/QUOTE]



Einstein (and many others) were not particularly happy with this notion of the observer having to be present at some critical state of observation (do animals and plants qualify too!) in order for some event (the moon rising for example) to happen in our everyday world or, to say "the moon only exists at that particular moment in time when I choice to watch it". Our whole sense of Scientific understanding seems to say otherwise, i.e. that there were loads of very important events going on this planet over millions of years, long before man came on the scene. Yet, quantum mechanics is very strange in that it puts the observer centre stage, rather than the mere objective observation and collection of facts.

Also you shouldn't use the word "deary" unless you work in Blackpool after ten at night

 

[Vanadium 50]

However it's possible that the reason why MBHs don't form in the high outer atmosphere maybe due to a case of matter starvation, there's literally no way for them to get going out there.

Good grief, this keeps getting sillier and sillier.

Let's review the "black holes are dangerous" argument. The first ingredient is that the coupling of TeV-scale black holes to matter is much stronger (like forty or fifty orders of magnitude) than we think. The next ingredient is that they don't immediately evaporate via Hawking Radiation - i.e. the coupling of TeV-scale black holes to matter is much weaker than we think - by the same forty orders of magnitude.

I'm willing to believe either that the coupling is much stronger or much weaker than we think it is - but not both at the same time.

Now there is the argument that this quasi-stable black hole doesn't go flying into space, because it's heavy and produced "at rest". Well, the heaviest black hole that can be produced is about 3 TeV, and >99.998% of all 3 TeV objects are produced moving faster than escape velocity. This depends only on the conservation of momentum. So we have to give that up too.

Now we have the argument that a cosmic ray induced black hole "doesn't get started" before it strikes the ground, unlike an accelerator produced black hole. That means it must evaporate before it strikes the surface, so it's Hawking lifetime must be less than 5 ns (in its rest frame) - actually much less, because this is the requirement for the average black hole, and we need to know the slowest black hole. Nonetheless, let's do the calculation and we find our less-than-escape-velocity black hole can travel no more than 7mm before it decays. That places it in the beampipe, where there is nothing but hard vacuum.

So the atmosphere isn't dense enough, but vacuum is? This makes no sense.

An earlier poster talked about "respect". As ZapperZ says, it cuts both ways - proposing an internally inconsistent fantasy is not very respectful. Furthermore, I think you don't appreciate how offensive you are being - do you really think that 5000 physicists are all such evil people that we are willing to murder six billion people (including our families and our friends) to perform an experiment? That each and every one of us is worse than Hitler, worse than Stalin, worse than Mengele? That none of us have a better developed set of ethics than a cartoon mad scientist?

If someone came up to you in a bar and called you a mad scientist worse than Mengele and a likely mass murderer, you might well punch him in the nose. But from scientists, you demand "respect."

Bah.

 

[james77]

Good grief, this keeps getting sillier and sillier.


So the atmosphere isn't dense enough, but vacuum is? This makes no sense.

Bah.

Wait and see what "makes sense" after the experiments are running a while. I have doubts about some of things that have been said. Anyway, that's my belief, enough said, we'll soon see what will or won't materialise with time, won't we?

 

[Vanadium 50]

Wait and see what makes sense after the experiments running a while. And you should stop insulting people too.

Your argument boils down to "the LHC is dangerous because vacuum is denser than atmosphere". That's silly.

If you want to feel insulted because you posted something silly, well, I can't control your feelings.

 

[james77]

Your argument boils down to "the LHC is dangerous because vacuum is denser than atmosphere". That's silly.

I don't think that the fact that the density can strongly increase in the chamber due to ion induced desorption is an irrelevant concern, this can indeed lead to a pressure runaway situation occurring. I don't feel this is a silly observation.

Perhaps what you say is indeed right, I do hope so.

Anyway, I will add nothing futher to this topic (which I sure you'll be glad about)

 

[vanesch]

A terrible idea just occurred to me

In fact, maybe the Tevatron is already producing tons and tons of micro black holes, who already started eating away a few atoms of the earth, and will take a few hundred years to grow to a size which will make them do detectable things ...

Maybe it even started out with the SPS at cern in the 80-ies, but we haven't found out yet...


:rofl:

 

[atyy]

A terrible idea just occurred to me

In fact, maybe the Tevatron is already producing tons and tons of micro black holes, who already started eating away a few atoms of the earth, and will take a few hundred years to grow to a size which will make them do detectable things ...

Maybe it even started out with the SPS at cern in the 80-ies, but we haven't found out yet...


:rofl:

OMG

Yes. It is my favorite. It's called the "many worlds interpretation"

Hopefully there's going to be at least one universe in which the Earth isn't destroyed:rofl:

 

[jms5631]

I ran across this article today from Physics World during a google search...I think it really puts the origin of the "1 in 50,000,000" odds given by Martin Rees in context, and also their irrelevance to black hole scanarios in the LHC. I only bring it up because the Rees odds are brought up so frequently in LHC discussions, that I think they demand explanation.

http://physicsworld.com/cws/article/indepth/30679

 

[vanesch]

It occurs to me that a submicroscopic black hole passing through an atom would either swallow nothing at all, or the nucleus as a whole, or one of the electrons. It would thereby acquire a charge, which would quickly be neutralised by its attracting the rest of the mutilated atom. But its trail through the human body might be surrounded by several secondary ionisation events. Thousands of these trails might pass through an inhabitant of Geneva on any given day.

Guess what ? That's already happening: thousands of ionisation trails are crossing your body EVERY SECOND. It's natural radioactivity...

 

[Orion1]

pseudo-scientific...


Administrators, this thread is pseudo-scientific fiction ad nauseam and has devolved into off topic ad hominem, please lock this thread and move it to skepticism and debunking.

Thanks.

 

[humanino]

Administrators, this thread is pseudo-scientific fiction ad nauseam and has devolved into off topic ad hominem, please lock this thread and move it to skepticism and debunking.

Please realize that this is an important topic. By locking the thread, you jeopardize the credibility of the scientific community as long as the public community is significantly worried. It is very painful for the scientific community, but it is the only way we can say we "respect the public".

 

[james77]

Please realize that this is an important topic. By locking the thread, you jeopardize the credibility of the scientific community as long as the public community is significantly worried. It is very painful for the scientific community, but it is the only way we can say we "respect the public".

Well, it's not just a case of the so-called Scientific Communities' respect for the general public. The CERN project must show a considerable degree of gratitude and respect to both the policy makers and the public across the EU who have given sizable sums (over the years) of money to this "affair", which is now being monitored extremely closely at such levels. If this project either goes wrong and doesn't deliver any significant or useful results, than there will be very little state or central support given to this type of scientific research in the future.

<It is very painful for the scientific community, but it is the only way we can say we "respect the public> It won't be as painful as getting your funding cut in the future.

Respect is the minimum that members of general public deserve.

 

[mal4mac]

Dr Adrian Kent, a seriously qualified quantum theorist of DAMPT at Cambridge, has worries:

"What's an Acceptable Risk for Destroying the Earth?

From time to time, people have raised the worry that a particular physics experiment just might destroy the Earth. The first time this was seriously considered seems to have been before the first A-bomb and H-bomb tests. More recently, the possibility was raised that, if unknown physics included some particularly unfortunate features, the RHIC experiments at Brookhaven, or the forthcoming ALICE collider experiments at CERN, could have disastrous consequences. When physicists address these worries at all, they've tended to argue that (a) something would have to be very wrong with our understanding of physics for the risk to be present at all, (b) even if it is, we can show on empirical grounds that any risk must be so small that the possibility just isn't worth worrying about. Which rather begs the question, of course: how small *is* an acceptable risk? On this point, the various analyses seem to have been extraordinarily cavalier. At various times physicists have argued for going ahead with experiments without further ado on the basis of risk bounds ranging from 1 in 5000 (!) (the first Brookhaven analysis of the RHIC experiments) through 1 in 300,000 (Compton's estimate of the probability of igniting the Earth's atmosphere in the first A-bomb test) to 1 in 50,000,000 (the CERN analysis of the RHIC experiments). It seems to me that a little thought suggests all these risk bounds are far, far too large for comfort."

http://www.damtp.cam.ac.uk/user/apak/research.html

http://arxiv.org/abs/hep-ph/0009204 Risk Anal. 24 (2004) 157-168

Also check out:

http://news.bbc.co.uk/1/hi/sci/tech/7468966.stm

It reports that CERNs top theorists are suggesting we shouldn't worry. I'd be much happier if Moscow and CalTech had produced such a comment. Aren't CERN theorists just slightly :-) interested parties? There's a one in many millions chance of Dr CERN-Theorist being exterminated if CERN goes online, but zero chance of them getting a Nobel if it doesn't! So the odds look great to them...