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

[humanino]

Kudos to Vanesch and others for discussing intelligently the real risks - or lack thereof - involved with the LHC, rather than dismissing people's concerns as "baloney" as others have.

Same applies to people requesting answers who have not dismissed published papers as "baloney"

 

[LowlyPion]

On another note CERN is getting flooded with phone calls from panicky people either pleading to shut the machine down or giving them death threats.

Some sceptics remain unconvinced about its safety. Prof Otto Rossler, a German chemist who is one of a group of scientists attempting a last-minute court challenge to the project, is especially worried about the creation of black holes.

I see this as a bad career move. If true, there won't be much upside - not many Nobels will be issued to recognize figuring it out when Sweden's gone - and of course in the case nothing of the sort happens, it just makes the fellow look foolish. (But then again he is a chemist opining on black holes?)

 

[mal4mac]

No. It is rather a subjective risk: we will do "new" things, and an exotic phenomenon which might have an evil effect can hence, by ignorance, not be excluded (just as vanadium's genie from the bottle). If we were really doing something unique in the LHC, then there would be no way to tell whether or not this might actually happen, and anybody's guess would be as good as any other.

Of course we are doing something unique with the LHC. If not, show me another LHC. The "genies" argument is spurious because no one is seriously suggesting that such genies can exist in any circumstance. But Kent, Rees, et.al. are pointing out that there is a very, very small but finite chance of black holes and strange matter appearing that could cause us problems. This chance seems to be so much smaller than even the chance of winning the lottery, that personally I'm not losing any sleep over it (for the same reasons I don't do the lottery!) But physicists should at least join Rees in a united front of admitting that an incredibly small risk of human annihilation does exist. Then they should trust the politicians and public to weigh that risk, and accept their decision on whether to take that risk or not.

 

[mal4mac]

From that Telegraph article:

"One of the leading figures behind the experiment is Dr Lynn Evans ... who said his fascination with science started as a boy, when he would create small explosions with his chemistry set at his council house in Aberdare.

Another is Prof Brian Cox of Manchester University, who played keyboards with D:Ream, whose hit Things Can Only Get Better was adopted by the Labour Party as its 1997 election anthem ... [he said] "Anyone who thinks the LHC will destroy the world is a t---."

Bet that makes the worried feel a whole lot better. Satire who needs?

 

[ZapperZ]

Of course we are doing something unique with the LHC. If not, show me another LHC. The "genies" argument is spurious because no one is seriously suggesting that such genies can exist in any circumstance. But Kent, Rees, et.al. are pointing out that there is a very, very small but finite chance of black holes and strange matter appearing that could cause us problems. This chance seems to be so much smaller than even the chance of winning the lottery, that personally I'm not losing any sleep over it (for the same reasons I don't do the lottery!) But physicists should at least join Rees in a united front of admitting that an incredibly small risk of human annihilation does exist. Then they should trust the politicians and public to weigh that risk, and accept their decision on whether to take that risk or not.

But here is where you need to think on how the public would interpret something like that.

One has to understand that in physics, almost everything has a non-zero probability of happening. There is a minute, but still, non-zero probability of an proton-antiproton pair appearing spontaneously out of thin air with enough energy that the LHC is producing to cause the same collision. Do we need to be worried about that?

Ask someone off the street how likely he/she think that a broken vase, when thrown onto the ground, would reassemble itself back into the vase? That person will likely tell you that it is NOT going to happen. Yet, in physics, there is still a non-zero but miniscule phase space where such an even CAN happen. So you have a general public that has decided that such an event is impossible, and physics that says that it most likely won't happen, but still, has a non-zero probability. Do we confuse the public by telling them that it cannot happen, or do we say, it won't likely to happen, but there's still a small probability that it can? How small are we talking about? Do we then have to make comparisons with things they know like being striked by lightning?

One simply cannot spew off statements to someone without understanding the level of comprehension of the listener. You may be saying one thing, but what you said can easily be misinterpreted by the listener. That is what scientists must always guard against. If I say that the formation of a catastrophic black hole at the LHC won't occur, I am using the level of understanding of a typical person who has already accepted that the vase will NOT reassemble itself from the hundred of pieces. If one accept that as not happening, then one should also accept other events with similar or lower probability of occurring.

Zz.

 

[Vanadium 50]

The "genies" argument is spurious because no one is seriously suggesting that such genies can exist in any circumstance.

You might not have been following "Islamic Science", which is sort of the muslim world's answer to creationism. They certainly think of genies - or djinn - as real.

I also don't think the world-eating black holes are "seriously suggested" either, at least not by anyone with a level of understanding sufficient to be serious. These putative objects, as has been pointed out by several people, have mutually contradictory properties. I don't see why an imaginary object with self-contradictory features is intrinsically more likely than a mythical being.

 

[ZapperZ]

Just in time for the first circulating proton beam at the LHC tomorrow, a http://physics.aps.org/articles/v1/14" of SLAC has appeared that analyzes the paper published by Giddings and Mangano, which, btw, is available for free.

Zz.

 

[james77]

But how can you guess what use something will be in the future if we don't understand it at present? Relativity, say, had no "use" when Einstein discovered it back in the 1900's, but I doubt you'd be able to live without it today!

You can´t guess what "use" any theortical concept will or will not have in the future, you have to develop a type of technology in order for any theory to be of use in the real world, and the notion of use implies value, which again is a relative term. As we all know the same Science can be used to develop very different things. But, the important point is that life can and indeed would continue to exist with or without the knowledge we have about Relativity, Electromagnetism or Particle Physics. It´s doubtful in terms of what values these subjects mean to humanity as a whole, what these discoveries have really mean´t to the average person on the street. Have the resultant technologies not further estranged people from each other, yet it would be foolish to deny the positive effects they have brought too.

 

[time traveller d]

if the LHC creates a black hole...

just wondering, if somehow a black hole is created by the LHC that can destroy the earth, would there be a way to close the black hole? or would we all just be doomed?

 

[vanesch]

Of course we are doing something unique with the LHC. If not, show me another LHC.

There are very high-energetic particles out there in space, you know. Particles which have millions or billions of times more energy than what we give them in the LHC. So there are no elementary processes happening in the LHC that haven't happened in the upper atmosphere, in Jupiter, etc...

The "genies" argument is spurious because no one is seriously suggesting that such genies can exist in any circumstance. But Kent, Rees, et.al. are pointing out that there is a very, very small but finite chance of black holes and strange matter appearing that could cause us problems.

I'm sorry but they can't. They can at most give you an UPPER BOUND to that probability. If they have a LOWER BOUND, which is what it means to say that there is a finite chance (that is, you state that it is not zero), then that means that they are SURE that such a reaction is physically possible, but they can't. There's only two ways to make such a statement scientifically, and that is by having observed it already, or by using firmly established principles to derive the happening. It has not been observed yet, I guess you can agree with that, but moreover, the principles on which one could even suggest it to happen are very very highly speculative (and have even to contradict things we thought we knew rather well, such as the second law of thermodynamics).

What is correct (see my post on subjective and objective probability) is that the best we can do is give an upper bound for the probability for something bad to happen under the hypothesis that it can happen - just like the genies from the bottle.

You have to understand where these "black hole theories" come from. For decades, theorists have been speculating (it's their job) about extensions of the standard model. In the beginning, they made observable predictions, but that had the disadvantage of being contradicted rather quickly with new observations. Then some of them embarked on very highly speculative ideas like string theory and the likes, which would normally give observable things only at such crazily high energies, that there was no hope ever to build a machine on Earth that would verify them. Then, they got the accusation that they were not really doing science, as their predictions would not be practically falsifiable. So they fiddled and twisted and turned their theories (that means, introduced funnier and stranger hypotheses) until they could make *something* eventually appear at LHC energies. That's why there are papers on the possibility of making micro black holes appear at the LHC. It's not that they sat down and said "gees, the LHC is going to produce black holes", they sat down and said "how can I change something in my theory SO THAT there might be a chance of the LHC to make black holes".
But until there, nothing dangerous, because if black holes respect the second law of thermodynamics, then they have to emit Hawking radiation - it would even be a feat to observe them before they blew up in random particles which would look as just an arbitrary collision.

 

[muppet]

So we're all about to die.

I've been thinking about what it would look like if the "ice-9" stranglet scenario actually happened, and the LHC turned the planet into strange matter. (I know this won't actually happen, but humour me )
As I understand it, the idea is that essentially all protons and neutrons would have their quark composition changed to uds, which is charge neutral. So watching the impending goo would be like watching everything getting ionized at once.
Two questions:
1)Would this just look like everything turning black?
2)Would the radiation kill us before we turned into strange matter?

Have a nice day now y'all

 

[muppet]

Oh and Cristo: the best thing about that Daily Mail article is the caption in which they state that physicists are trying to recreate the conditions of the big band

 

[Ontoplankton]

Do any of you happen to know whether there's a nonzero (or greater than let's say one in a million) chance of accidental universe creation at LHC, as is sort of suggested here: http://www.newscientist.com/channel/fundamentals/mg19125591.500-create-your-own-universe.html ? If there is, then does nature do it also? It wouldn't affect us if it happened but it still seems ethically dubious.

 

[chippy!]

hey guys I am new to the forum :) I am very interested in space etc and i know quite a lot i think, well for an average 18 year old. ( i got a C GCSE in single science lol, don't know why i meantioned that.) anyway i have a few questions about this LHC, that hopefully a few more educated people could answer.
is it just me or is this experiement very risky? putting the whole world at risk just for an experiment?
anyway, here are a few questions?
black holes are created when high amount of energy/mass is concentrated down to a small point, am i right?
so didnt they say that their sending billions of protons down a tube only a hair's length wide? how much energy/mass are they concentrating down into this tube and with how much force?
they say that nature is creating these collisions all the time, but in the LCH these collisions will be concentrated in a small area with no room for the particles to spread out.
also when the protons collide together they said micro black holes might be created but how many exactly? they also said they would evaporate but what if lots are created and some formed together before they evaporated? i mean like they merge into a bigger black hole which doesn't evaporate.
finally if you did have 1 single micro black hole that didnt evaporate, how much damage could it possibly do?
thanks!

 

[ZapperZ]

Please read the link I gave in Msg. #165.

Zz.

 

[chippy!]

Please read the link I gave in Msg. #165.

Zz.

i have just read it but its a bit too deep for my understanding. the formulas are meaningless to me :S sorry

 

[ZapperZ]

i have just read it but its a bit too deep for my understanding. the formulas are meaningless to me :S sorry

Then you need to consider the possibility that maybe, this might be a bit difficult to comprehend for you, and that at some point, you have to depend on the experts who have done quite a bit more studies on the nature of the risk. I'm not saying that you shouldn't ask. But when you question the validity of the safety conclusion, then you need to present your objection not based on ignorance.

The same can be said about the formation of such "black holes". You can see the difficulty in explaining the nature of such black holes, or what Peskin called "slippery" black holes, if you do not have the capability of understanding the physics. Try explaining geometry to a 2-year old and see if he/she can solve a trig problem after that. This doesn't mean you shouldn't ask, but you need to be aware that the problem isn't easy and require a lot of "prerequisites" to comprehend.

Zz.

 

[chippy!]

Then you need to consider the possibility that maybe, this might be a bit difficult to comprehend for you, and that at some point, you have to depend on the experts who have done quite a bit more studies on the nature of the risk. I'm not saying that you shouldn't ask. But when you question the validity of the safety conclusion, then you need to present your objection not based on ignorance.

The same can be said about the formation of such "black holes". You can see the difficulty in explaining the nature of such black holes, or what Peskin called "slippery" black holes, if you do not have the capability of understanding the physics. Try explaining geometry to a 2-year old and see if he/she can solve a trig problem after that. This doesn't mean you shouldn't ask, but you need to be aware that the problem isn't easy and require a lot of "prerequisites" to comprehend.

Zz.

no, i am able to understand if someone just answered my questions directly. if someone was to explain it simply without the full in depth 'workings out'. is that too much to ask?

 

[vanesch]

Do any of you happen to know whether there's a nonzero (or greater than let's say one in a million) chance of accidental universe creation at LHC, as is sort of suggested here: http://www.newscientist.com/channel/fundamentals/mg19125591.500-create-your-own-universe.html ? If there is, then does nature do it also? It wouldn't affect us if it happened but it still seems ethically dubious.

My god. New Scientist sunk to the depth of a black hole

This is entirely speculative, but moreover, this is not science, as it is not falsifiable in principle.
What is said here is that WE would observe a micro black hole, but that "in fact" it is an entire universe, but we won't find out.

 

[vanesch]

no, i am able to understand if someone just answered my questions directly. if someone was to explain it simply without the full in depth 'workings out'. is that too much to ask?

Read through this thread, and you might get an idea.

 

[chippy!]

Read through this thread, and you might get an idea.

well i have read 2-3 pages but there is a lot to take in at once.
ok can i just ask, seeing as no-one wants to answer my questions.
overall then regarding this LHC experiement what are the odds of creating any black hole, of any size or length of time?

 

[ZapperZ]

no, i am able to understand if someone just answered my questions directly. if someone was to explain it simply without the full in depth 'workings out'. is that too much to ask?

Let's look at your first question:

is it just me or is this experiement very risky? putting the whole world at risk just for an experiment?

If I just answered "No", would you be satisfied? Many people won't. And in fact, giving you just the answer "no" would be insulting to you, because it assumes that you will except everything that I tell you without proper justification. So now, it is THAT proper justification that is the issue here.

The link I gave you, while it is quite technical, has ALL the necessary answer. You can read the first few paragraphs to clearly get the answer to this particular question. Even his example from astrophysical observation should have a convincing argument that nature has done a lot more "LHC-type" experiments than the LHC would ever hope of doing. This you should have noticed clearly enough as the answer to your question.

Zz.

 

[chippy!]

Let's look at your first question:



If I just answered "No", would you be satisfied? Many people won't. And in fact, giving you just the answer "no" would be insulting to you, because it assumes that you will except everything that I tell you without proper justification. So now, it is THAT proper justification that is the issue here.

The link I gave you, while it is quite technical, has ALL the necessary answer. You can read the first few paragraphs to clearly get the answer to this particular question. Even his example from astrophysical observation should have a convincing argument that nature has done a lot more "LHC-type" experiments than the LHC would ever hope of doing. This you should have noticed clearly enough as the answer to your question.

Zz.

ok, I am not one of these people against the experiment , I am sitting on the fence.
its just confussing me that why are some scientists saying that it isn't safe? do they have a vaild theory or reason why it could go wrong? i

 

[ZapperZ]

well i have read 2-3 pages but there is a lot to take in at once.
ok can i just ask, seeing as no-one wants to answer my questions.
overall then regarding this LHC experiement what are the odds of creating any black hole, of any size or length of time?

You need to keep in mind that creating black holes is something they WANT. This isn't the issue. If GR is correct in this energy scale, then creating these micro black holes would not be surprising. I know of many people who would LOVE to be able to create AND detect them.

The issue is (i) the nature of such black holes and (ii) that they become stable and can create a catastrophe. This is the scenario that is creating such a brouhaha in the media. This is what has been argued to be extremely unlikely. It is as likely as you spontaneously vanishing.

Zz.

 

[ZapperZ]

ok, I am not one of these people against the experiment , I am sitting on the fence.
its just confussing me that why are some scientists saying that it isn't safe? do they have a vaild theory or reason why it could go wrong? i

There are also "scientists" who claim Evolution is wrong. You need to separate out fringe opinions versus the majority, and in this case, an overwhelming majority.

Read Peskin viewpoint again, and pay attention to where he describes the level of assumption and theoretical speculation that is required to work out these things. This is where someone can pull out some numbers beyond what we have verified so far to come up with such disasters. As vanesch has mentioned earlier, many of these are not falsifiable as of yet, so you can simply speculate way. The key here is when we look at things that are reasonable, such as the astrophysical observation that we already know, these things just do not happen. The fact that the Moon is still there (to paraphrase the RHIC safety report) tells us that these experiments are not going to create such catastrophe.

Zz.

 

[chippy!]

You need to keep in mind that creating black holes is something they WANT. This isn't the issue. If GR is correct in this energy scale, then creating these micro black holes would not be surprising. I know of many people who would LOVE to be able to create AND detect them.

The issue is (i) the nature of such black holes and (ii) that they become stable and can create a catastrophe. This is the scenario that is creating such a brouhaha in the media. This is what has been argued to be extremely unlikely. It is as likely as you spontaneously vanishing.

Zz.

ok thanks for your response. i take it that the odds are way against these stable BH's then?
well it still makes me feel a bit uneasy that we might be creating these black holes whatever the size to be honest.
are the scientists at all aprehensive? becasue didnt one of them say they don't actually know what will happen in this experiment?

 

[vanesch]

You need to keep in mind that creating black holes is something they WANT. This isn't the issue. If GR is correct in this energy scale, then creating these micro black holes would not be surprising.

Uh, it would be a very peculiar kind of GR, in many dimensions, which are curled up on larger scales than we would think, which would allow black holes to be created in the first place. Most "standard" physics wouldn't even come close in creating a black hole in the LHC, or even in the VLHC (Very Large Hadron Collider) or the ILHC (Insanely Large Hadron Collider). Creating black holes at "puny" energies of 14 TeV as compared to the Planck scale is by all "normal" means entirely impossible, and you have to twist and turn spacetime in funny shapes for it to become even conceivable (which is what theorists have done). Of course, this means that it is not *inconceivable*, as it has been conceived theoretically. If ever there is a signature of black hole creation in the LHC, then the theorists that wrote this down won the biggest bet they ever took.

But, based upon the same kind of theoretical reasoning, and on much firmer grounds, we know that IF micro black holes exist, they should evaporate almost instantaneously. So for micro black holes to form, and for them not to evaporate, would need two giant leaps out of established theory.

Finally, EVEN if this were conceivable, it cannot happen very often, as Zz pointed out, because "the moon is still there".

 

[ZapperZ]

ok thanks for your response. i take it that the odds are way against these stable BH's then?
well it still makes me feel a bit uneasy that we might be creating these black holes whatever the size to be honest.
are the scientists at all aprehensive? becasue didnt one of them say they don't actually know what will happen in this experiment?

Look, one of my friends here at work will be going there to become an assistant physics coordinator for ATLAS. Do you think he'll be there if he is even a little bit apprehensive? There will be hundreds of people working there during first collision. Do you think they are at all apprehensive? I would be there too if I can find a rational and valid reason for being there (I have none). I have absolutely zero apprehension. And as I've said earlier, the person most concerned about my safety and well-being is ... ME!

So you can draw up your own conclusion from this.

Zz.

 

[ZapperZ]

Uh, it would be a very peculiar kind of GR, in many dimensions, which are curled up on larger scales than we would think, which would allow black holes to be created in the first place. Most "standard" physics wouldn't even come close in creating a black hole in the LHC, or even in the VLHC (Very Large Hadron Collider) or the ILHC (Insanely Large Hadron Collider). Creating black holes at "puny" energies of 14 TeV as compared to the Planck scale is by all "normal" means entirely impossible, and you have to twist and turn spacetime in funny shapes for it to become even conceivable (which is what theorists have done). Of course, this means that it is not *inconceivable*, as it has been conceived theoretically. If ever there is a signature of black hole creation in the LHC, then the theorists that wrote this down won the biggest bet they ever took.

I don't think it is based on any "standard" physics, If you read the Peskin link, he describe one scenario for such formation, which is what you have in mind, I think:

Particle collisions at energies above the Planck scale must create black holes, because they put large amounts of energy within a small enough region (the so-called Schwarzschild radius). Giddings and Thomas [6] and Dimopoulos and Landsberg [7] realized that this logic, applied to the ADD model, implies that high-energy collisions at TeV energies should produce black holes. They did not consider this a danger but rather an exciting possibility. They imagined that the black holes would glow with a temperature of about 1 TeV/kB, emit large numbers of quarks, leptons, and bosons through Hawking radiation [8], and evaporate in 10-26 s. This process would produce unique and unmistakable events detectable by the LHC experiments.

Zz.

 

[mal4mac]

But here is where you need to think on how the public would interpret something like that.

I totally agree. The BBC should have broadcast many hours of public debate with Rees, Kent CERN scientists, etc. Then matters of interpretation could have been fully dealt with and, hopefully, death threats avoided. But the level of public debate, at least in the UK, is severly limited. The BBC are totally failing their public service remit in not fully delving into issues like this.

One has to understand that in physics, almost everything has a non-zero probability of happening. There is a minute, but still, non-zero probability of an proton-antiproton pair appearing spontaneously out of thin air with enough energy that the LHC is producing to cause the same collision. Do we need to be worried about that?

No physicists are arguing that this is a serious threat. Some physicists are arguing that the LHC is a threat, albeit a remote one.

Ask someone off the street how likely he/she think that a broken vase, when thrown onto the ground, would reassemble itself back into the vase? That person will likely tell you that it is NOT going to happen. Yet, in physics, there is still a non-zero but miniscule phase space where such an even CAN happen. So you have a general public that has decided that such an event is impossible, and physics that says that it most likely won't happen, but still, has a non-zero probability. Do we confuse the public by telling them that it cannot happen, or do we say, it won't likely to happen, but there's still a small probability that it can? How small are we talking about? Do we then have to make comparisons with things they know like being striked by lightning?

We tell them the truth, of course!

One simply cannot spew off statements to someone without understanding the level of comprehension of the listener. You may be saying one thing, but what you said can easily be misinterpreted by the listener. That is what scientists must always guard against. If I say that the formation of a catastrophic black hole at the LHC won't occur, I am using the level of understanding of a typical person who has already accepted that the vase will NOT reassemble itself from the hundred of pieces. If one accept that as not happening, then one should also accept other events with similar or lower probability of occurring.

And then "the Dail Mail" newspaper takes an out of context quote from Rees' book saying exactly the opposite to you. So not only do they frighten the reader about black holes but they show that physicists are either disagreeing with each other on this mattere of deadly concern, or one of them is lying, or one of then is treating the public like idiots. Why not just tell then the truth in terms they can understand -- like saying the risk is the same as the same person winning the lottery x weeks in a row