Could the Large Hadron Collider Create a Black Hole That Threatens Earth?

[Vanadium 50]

If this machine is "so safe" why are all these distinguished scientists fighting so hard against it?

Which distinguished scientists?

Some of these guys ARENT nutballs.

Which ones? They all seem like nutballs to me. Particularly those who are advocating violence - see ZapperZ's blog for an interesting response.

 

[arivero]

Hey everyone. Sorry if this topic has been played to death, but like many, I'm having pretty high anxiety about the start up of the LHC in a few weeks. Just got engaged, new job, life is really starting for me. I'm afraid it might be cut short cause of this thing.

As a joke it starts to wear. But still I like this one, with an hidden scent of irony about how the world works (not in the GUT/TOE sense, but in the sense of engaged + get a life + progress etc)

 

[james77]

Which distinguished scientists?



Which ones? They all seem like nutballs to me. Particularly those who are advocating violence - see ZapperZ's blog for an interesting response.

Which ones. Well see Giddings & Mangano for example and, Plaga as noted in his paper on the 10th August 2008 and again Martin Rees in numerous articles. These guys cannot be dismissed, arrogantly as "Nutjobs". To do so is not only ignorant and offensive but deeply stupid too, as any scientific theory evolves through a process of constant refinement between inherent possibilities, and some of these possibilities are initially identified as risks. Remember Einstein's infamous but highly understandable concerns before the first nuclear tests in July 1945?

 

[Vanadium 50]

Which ones. Well see Giddings & Mangano for example

As examples of scientists "fighting hard against the LHC"? This is a total misrepresentation of their report.

As far as "arrogance", I marvel at the state of affairs where someone who criticizes a report that they don't understand isn't being arrogant, but where someone who points this out is.

 

[vanesch]

One shouldn't forget that the LHC is not such an exceptionally more powerful machine than are other colliders. Tevatron has ~ 2 TeV c.o.g. energy, LHC will have 14 TeV, just 7 times more. It is just because theorists have been idle for several decades that they came up with micro black holes at LHC.
The step from accelerators to colliders was a bigger step than from the Tevatron to the LHC.

 

[Cvan]

They speculated that they could ignite the atmosphere of the Earth ablaze when they dropped the first nuclear bomb.

They speculated Columbus would fall off the edge of the world on his trip.

And now they're speculating that there's a remote possibility of creating something that has never been directly observed, and would, in any case--basically evaporate in such a fashion that the only way to know it was ever there would be after years of testing the data. And people are worried about this.

What has the world become?

 

[humanino]

<mode=general discussion>

What has the world become?

Again : when did the world change ?
</mode>

 

[jms5631]

Which ones. Well see Giddings & Mangano for example and, Plaga as noted in his paper on the 10th August 2008 and again Martin Rees in numerous articles.

Giddings and Mangano? Mangano was part of the group who studied the 2003 report and reaffirmed its safety. Then both went into even more depth in a second paper specifically exploring the question of the possibility of macroscopic, stable black holes, and here again validated the LHC as safe. I do not see how you can consider either of these scientists as people voicing their concerns about the safety of the LHC when they've specifically confirmed its safety. As for Rees, I don't know what numerous articles you're referring to...I've only heard him give the chances of anything unexpected happening at no more then 1 in 50,000,000(take note this is the upper limit of any supposed likihood, not necessarily the actual one). Even this seemingly remote possibility has been criticized as far too high by many physicists. As far as I can tell, out of the men you've listed, Plaga is the only one who legitimately supports this point of view.

 

[vanesch]

Remember Einstein's infamous but highly understandable concerns before the first nuclear tests in July 1945?

If you are referring to "igniting the atmosphere", then that's definitely not Einstein, but... Edward Teller ! And it was Hans Bethe who showed him wrong by several orders of magnitude. It's pretty ironic, because after that, Teller's obsession was... to make a hydrogen bomb!

 

[james77]

The Hungarian physicist Leo Szilard spoke to Einstein about the consequence of a uranium based chain reaction occurring after denotation. Quote 'The possibility of a chain reaction in uranium hadn't occurred to him, but as soon as I began to tell him about it he saw what the consequences might be.' A letter, signed by Einstein, was then sent to the American president, Franklin Roosevelt. This meeting occurred in a few months in advance of the first test.

On the subject of safe stable MBHs, yes indeed they may be safe (theoretically) to a certain point, but beyond the initial thresholds set, I think that it's difficult to make a prediction with regard to their ultimate stability and durability. Maybe they will vaporise as quickly as they were created, then again perhaps not. To be truthful we don’t really know, yet I imagine any catastrophic outcome is really a remote possibility as the experiments are being done in carefully controlled, graduated manner.

 

[ZapperZ]

On the subject of safe stable MBHs, yes indeed they may be safe (theoretically) to a certain point, but beyond the initial thresholds set, I think that it's difficult to make a prediction with regard to their ultimate stability and durability. Maybe they will vaporise as quickly as they were created, then again perhaps not. To be truthful we don’t really know, yet I imagine any catastrophic outcome is really a remote possibility as the experiments are being done in carefully controlled, graduated manner.

Still, what Vanadium and jms5631 are countering is your point that "all these distinguished scientists..." are fighting against the LHC, when no such thing is occurring. We have to be careful when we make statements like that, especially when this is a public forum and Google spiders pick those up quickly.

The "uncertainty" in knowing what will happen, if that is your argument, works both ways. If you criticize the LHC safety report that "we don't really know" about the consequences of the collision, then you also have to be equally critical of arguments that claim that it isn't safe, because such arguments will also, at the very least, make use of the same uncertain physics.

As far as I can tell, so far, you've only argued this simply based on a matter of tastes, which you must admit, isn't really conducive to any kind of rational, scientific discussion. There are many of us who have accepted the LHC report. There are also a few of us who went through the same brouhaha when RHIC was about to go online and remembered the same type of discussion. Unless the middle of Long Island has disappeared without the rest of the world knowing it (it was there a few months ago when I last checked), nothing came of it and the analysis that was done back then was obviously valid. So there IS a track record of success in this and it showed that we are not completely clueless. Rather, those who actually were predicting doom and gloom for RHIC were the one shown to be clueless (how come those people never trumpeted their failures now?). The LHC safety review is significantly more extensive than RHIC's. And these were not done by some no-name individuals either.

At some point, you need to consider if you are just going out on a fishing expedition, or if you truly have some indication from physics that this isn't safe. Doing the former is highly irresponsible, because you could shut down every single scientific advances that you are enjoying right now (I can tell you the horror outcome of superconducting technology that can fill pages, all via a fishing expedition).

Zz.

 

[vanesch]

The Hungarian physicist Leo Szilard spoke to Einstein about the consequence of a uranium based chain reaction occurring after denotation. Quote 'The possibility of a chain reaction in uranium hadn't occurred to him, but as soon as I began to tell him about it he saw what the consequences might be.' A letter, signed by Einstein, was then sent to the American president, Franklin Roosevelt. This meeting occurred in a few months in advance of the first test.

The meeting between Szilard and Einstein was years before the first test and that letter was actually a plea to develop a nuclear weapon, because Einstein's main worry was that Nazi-Germany might be developing one.
The issue of the ignition of the atmosphere had been discussed with Oppenheimer, Bethe, Szilard and others, and they came to the conclusion that it wasn't possible (based upon Bethe's corrections of Teller's wrong estimations), and all of them were after that convinced that no such thing could happen, although *rumors* circled (call them urban legends) that this wasn't the case.

It is true that Szilard wasn't happy with the way the politicians had taken control of the atomic bomb project (which he considered "his" invention), and he wanted to air his disagreement about that to Roosevelt, but it had nothing to do with igniting the atmosphere.

You can read the 4 letters that Einstein wrote right here:
http://hypertextbook.com/eworld/einstein.shtml

 

[jms5631]

On the subject of safe stable MBHs, yes indeed they may be safe (theoretically) to a certain point, but beyond the initial thresholds set, I think that it's difficult to make a prediction with regard to their ultimate stability and durability. Maybe they will vaporise as quickly as they were created, then again perhaps not. To be truthful we don’t really know, yet I imagine any catastrophic outcome is really a remote possibility as the experiments are being done in carefully controlled, graduated manner.

Have you read the safety analysis done by Giddings and Mangano? If not you really should head over to arivX and check it out. All the concerns you've voiced, I believe have been reviewed and answered in great depth in that paper...they've taken practically every contingent scanerio in which mini black holes would form, and ruled out any likelihood worth noting of their evolution into a stable, macroscopic one. In all likelihood, we're not even going to get unstable mini-black holes out of this machine, and the chances of anything unexpected happening are small enough to disregard.

 

[james77]

<At some point, you need to consider if you are just going out on a fishing expedition, or if you truly have some indication from physics that this isn't safe. Doing the former is highly irresponsible, because you could shut down every single scientific advances that you are enjoying right now (I can tell you the horror outcome of superconducting technology that can fill pages, all via a fishing expedition)>

I agree with the general premise of what you say above and, the point you make about the arguments that were circulated in advance of the RHIC are indeed both valid and timely. However, the results of this experiment do have the capacity, as indeed the first test of the atomic bomb on the 16/07/1945 in San Antonio had, to change totally not just Physicists, but humanities and indeed every living organisms’ relationship (and relationship is a key term here) positively or negatively to what constitutes our environs upon this planet.

O.K, say now comes the point where you tell me that this is a Philosophical/Ethnical consideration and that it shouldn’t be a real consideration that which pertains to the scientific experiments that will be conducted shortly. However, without digressing too much on this ethnical topic, all I can say (and this has been discussed as noted, excessively over the years) is that the possible knowledge gained from this experiment should be ideally weighted against the thought of risks and possible risks that may only become apparent during the experiments at different, unique stages of progression. There’s the possible scenario for example that at a certain stage during the experiments, well into the process that the possible risks may increase exponentially after a critical phase, because of the knowledge gained.

With regard to the Physics in question. I think the question of whether an Eddingtion limit can be established is of paramount importance. If evidence of such a limit becomes discernible during the initial stages of the experiment at the Thomson cross-section, assuming the radiation is photons, it will naturally exert a force where-






At this point there is the possibility of an exponential growth with t, of a MBH, assuming the above can balance the force of gravity pulling m, assuming m is the average atomic mass per electron), inwards.

Again, at this stage such a scenario may seem to be remote, but later on-going experimental data could perhaps prove otherwise.

I largely agree with a later poster’s view (that a least theoretically at this stage) that the likelihood of getting an array of unstable MBHs being produced by this machine is remote yet I don’t think that the risk can be totally dismissed just because it’s small, after all small is a very relative term in this context.

My equation seems to be unable to be applied on this page? It was the Thomson-coross scetion

 

[ZapperZ]

<At some point, you need to consider if you are just going out on a fishing expedition, or if you truly have some indication from physics that this isn't safe. Doing the former is highly irresponsible, because you could shut down every single scientific advances that you are enjoying right now (I can tell you the horror outcome of superconducting technology that can fill pages, all via a fishing expedition)>

I agree with the general premise of what you say above and, the point you make about the arguments that were circulated in advance of the RHIC are indeed both valid and timely. However, the results of this experiment do have the capacity, as indeed the first test of the atomic bomb on the 16/07/1945 in San Antonio had, to change totally not just Physicists, but humanities and indeed every living organisms’ relationship (and relationship is a key term here) positively or negatively to what constitutes our environs upon this planet.

What exactly are these environmental concerns? If a black hole forms that can swallow the earth, the LAST thing we would want to care about is such environmental concerns.

Again, these are rather undefined issues that you have brought up. In fact, it is exactly the fishing expedition that I had just presented. In other words, you don't quite know what exactly will happen, but you're just throwing out a bunch of stuff, hoping something would stick, or something would seem remotely valid.

With regard to the Physics in question. I think the question of whether an Eddingtion limit can be established is of paramount importance. If evidence of such a limit becomes discernible during the initial stages of the experiment at the Thomson cross-section, assuming the radiation is photons, it will naturally exert a force where-

At this point there is the possibility of an exponential growth with t, of a MBH, assuming the above can balance the force of gravity pulling m, assuming m is the average atomic mass per electron), inwards.

Again, at this stage such a scenario may seem to be remote, but later on-going experimental data could perhaps prove otherwise.

I largely agree with a later poster’s view (that a least theoretically at this stage) that the likelihood of getting an array of unstable MBHs being produced by this machine is remote yet I don’t think that the risk can be totally dismissed just because it’s small, after all small is a very relative term in this context.

Well, do you stop going out of your house because you're concern that you might get struck my lightning? Or do you avoid living in all or any parts of the world because there is a risk of earthquake, tornadoes, hurricanes, etc.. etc? If you don't, then maybe consider those risks versus the assessed risk of such things forming at the LHC and decide for yourself how rational and inconsistent you are in your concerns.

Zz.

 

[james77]

<Again, these are rather undefined issues that you have brought up. In fact, it is exactly the fishing expedition that I had just presented. In other words, you don't quite know what exactly will happen, but you're just throwing out a bunch of stuff, hoping something would stick, or something would seem remotely valid>

Yes, indeed the issues may well be undefined or even "fuzzy", but some of the findings that may occur from this experiment may well have to accommodated into categories that are not exactly neat and cosy in any conventional sense.

<In other words, you don't quite know what exactly will happen> Do you know what's going to happen, EXACTLY!

<Well, do you stop going out of your house because you're concern that you might get struck my lightning? Or do you avoid living in all or any parts of the world because there is a risk of earthquake, tornadoes, hurricanes, etc. etc? > Of course not, these are local, definable risks that have a certain probability of occurring over a certain period time, in a certain place, usually in a certain proscribed way or manner that allows a degree of prediction to occur. In other words, one can know what to expect within a finite space of time. You cannot compare these examples to the CERN project.

<If you don't, then maybe consider those risks versus the assessed risk of such things forming at the LHC and decide for yourself how rational and inconsistent you are in your concerns> I don't think my views have been either inconsistent or irrational. I have simply just noted that there is a very low risk scenario that there could be a negative result (s) based upon different possible outcomes that have been quite widely discussed amongst Scientists for some time now. I don't believe stating this should mean that one automatically becomes assigned to the lunatic fringe! How odd and irrational that would be!

 

[ZapperZ]

<Again, these are rather undefined issues that you have brought up. In fact, it is exactly the fishing expedition that I had just presented. In other words, you don't quite know what exactly will happen, but you're just throwing out a bunch of stuff, hoping something would stick, or something would seem remotely valid>

Yes, indeed the issues may well be undefined or even "fuzzy", but some of the findings that may occur from this experiment may well have to accommodated into categories that are not exactly neat and cosy in any conventional sense.

I have no idea what you just said here. My argument of things that are rather undefined referred to what you described earlier. It has nothing to do with the experimental results of what we get out of the LHC.

<In other words, you don't quite know what exactly will happen> Do you know what's going to happen, EXACTLY!

No, but that is referring to the experimental results themselves. There's certainly MORE known about what will likely NOT to occur. And if I were to ask you if you think you know more about what will occur versus those physicists who wrote the LHC safety report, who do you think will win that?

<Well, do you stop going out of your house because you're concern that you might get struck my lightning? Or do you avoid living in all or any parts of the world because there is a risk of earthquake, tornadoes, hurricanes, etc. etc? > Of course not, these are local, definable risks that have a certain probability of occurring over a certain period time, in a certain place, usually in a certain proscribed way or manner that allows a degree of prediction to occur. In other words, one can know what to expect within a finite space of time. You cannot compare these examples to the CERN project.

<If you don't, then maybe consider those risks versus the assessed risk of such things forming at the LHC and decide for yourself how rational and inconsistent you are in your concerns> I don't think my views have been either inconsistent or irrational. I have simply just noted that there is a very low risk scenario that there could be a negative result (s) based upon different possible outcomes that have been quite widely discussed amongst Scientists for some time now. I don't believe stating this should mean that one automatically becomes assigned to the lunatic fringe! How odd and irrational that would be!

The examples I gave was in response to you stating that "small" is a "relative" term. So I asked you to compare the various aspect of several things that had "small" risks. If you live your life by assuming that such small risks are insignificant to affect your day-to-day decisions, then you need to look at the risk assessment of the LHC. Unless you have some valid reason to say that such risk assessment is not valid and that it is actually significantly higher than the group of "small risk" items that I've listed, then this whole issue is moot.

Zz.

 

[jms5631]

Look, the advent of quantum mechanics led to a radical new era in science: the end of certainty. We can only look at things probalistically, and thus must utilize proper risk assessment in all our endeavors. Concerns about safety, especially with some of the highly hypothetical situations presented are justified; the onus is on the scientists to demonstrate that this machine is "safe." No risk can be lowered to exactly zero, but what has been proven is that the risk is so incredibly remote, that in practical terms it can be disregarded. The day to day situations that Zapper Z brought up, which are far-fetched scanerios you likely don't give a second thought to, are statistically several orders of magnitude more likely then anything happening at the LHC. So if you consider walking down the street safe, then the LHC should be no problem. I agree with you that if a risk of any substance of something happening that could alter the lifetime of the Earth in comparison with the life expectancy of the solar system could be demonstrated, then it must be take seriously. However, that is not the case, and the best scientists in the world have comprehensively certified this machine as safe. The lower energy limits in the LHC have already been probed in the Tevatron, and its capibilities are only a few orders of magnitude higher then the Tevatron, as Vanesch pointed out. There really is no cause for concern.

 

[james77]

<Look, the advent of quantum mechanics led to a radical new era in science: the end of certainty> This is of course true up to a point, yet the everyday Euclidean world of casual objects is still mostly determined by the Laws of classical Physics, Newton's Laws of motion for example, which allow one to make certain accurate, repeatable predictions about physical objects under various conditions in the world, still hold as good today as they did before the 20th century. Yes, it is certainly true that quantum mechanics has introduced a relative degree of uncertainty into our conceptual understanding and consequential mathematical modelling of the world at this microscopically tiny level. However, sometimes people make the mistake of describing quantum mechanics as a theory that seems to operate or be only applicable in a universe that gives the appearance of being totally apart from the classical, Euclidean everyday world of Newtonian Physics. While in essence quantum mechanics does indeed contain the uncertainty you mentioned, up until now it has being difficult to describe the effects of this theory in the classical everyday Newtonian world.

< We can only look at things probalistically> In the quantum world this is very true, I think some of the possibly huge beneficial side-effects of the CERN project may relate to our mathematical understanding with regard probability and how it can be modeled in the real world.

< No risk can be lowered to exactly zero, but what has been proven is that the risk is so incredibly remote, that in practical terms it can be disregarded> I do and have largely concurred with this belief, despite what others may of thought on my early posts.


<I agree with you that if a risk of any substance of something happening that could alter the lifetime of the Earth in comparison with the life expectancy of the solar system could be demonstrated, then it must be take seriously> I just think (as mentioned earlier) that any potential “real” risk or risks will only become apparent during the evolution of this process (if indeed they ever materialize)

< The lower energy limits in the LHC have already been probed in the Tevatron, and its capibilities are only a few orders of magnitude higher then the Tevatron> Yes, but I think these few orders of magnitude are critical.

Regards

 

[humanino]

Since serious papers have been posted, and do not seem to convince some people, I'll post an opinion, just for fun :
(I have not seen it posted earlier, at least not in this thread)
What Will the LHC Find? (Sean Carroll)

• [...]
• Black Holes: 0.1%. One of the intriguing aspect of brane-world models is that gravity can become strong well below the Planck scale — even at LHC energies. Which means that if you collide particles together in just the right way, you could make a black hole! Sadly, “just the right way” seems to be asking for a lot — it seems unlikely that black holes will be produced, even if gravity does become strong. (And if you do produce them, they will quickly evaporate away.) Fortunately, the relevant models make plenty of other predictions; the black-hole business was always an amusing sidelight, never the best way to test any particular theory.
• Stable Black Holes That Eat Up the Earth, Destroying All Living Organisms in the Process: 10^-25%. So you’re saying there’s a chance?
• [...]
• God: 10^-20%. More likely than stable black holes, but still a long shot.
• [...]

 

[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...

 

[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...

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

 

[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