Why do you people need to get in the situation of needing hadrotherapy before you can realize that science can do a lot of good to your life ?

Cheers,
T.

And then, armed with my terrible weapon, I would be free to aim it at mosquitos and FRY them. Buahahahahaha!

Suicidal Madman: When this here partical exelorator lights up, my dream will finally come true. I’ll be so dead!

Concerned Layman: You madman, I’ll kill you!

Suicidal Madman: Thanks!

James, you missed your calling as a writer for the RNC. But have no fear, if your comic book visions come to fruition you won’t have to worry about paying the bills after GW’s “suicidal madmen” unleash their fatal atoms. This should give you the perfect opportunity to blow your life savings this weekend with peace of mind. No matter the results, you have the comfort of knowing that your personal molecular structure will never escape the physical universe as we know it. Too bad, but you’re about 40 years too late to be a candidate for The Electric Kool-Aid Acid Test bus tour. On a more serious note, I have read several accounts of LHC scientists receiving death threats. Incredible.

You are implicitly assuming that “scientists” (particle physicists really) are suicidal madmen who wouldn’t hesitate to kill themselves, their own families and everybody else just in order to run a particular experiment, although the ensuing End Of The World will obviously prevent them from actually experiencing the experiment being run.

I wonder where this bizarre image of “scientists” came from. I can understand “stuffy, arrogant nerds”, even “parasitic jerks”, but suicidal madmen?!?

for those who dont know its a giant partical exelorator or atom smasher as its sometimes called ., they send the atom paticals one way and send some the opposite way in a circular tube at nearly the speed of light and crash them into eachother but dont worry the scientists said its safe , but could cause micro black holes and other earth threatning substances!!

im all for science but not when it takes the risk of lives.. and especially taking the risk of the whole planet! these scientists assure us its safe.. they cant even agree what excactly will happen.. some say there wont be black holes ,some say there will ,some say they will fizzle out some say they will swallow us and everthing else up.

smashing atoms , micro black holes, starlets, funny matter?? any one of these things could end it all,, yeah right really sounds safe this experiment these scientists couldent even spot a simple design fault of the LHC equipment,.. and they are telling us they can predict the experiment its self on theories? theories can be wrong.! and what ive read different scientists have different theories on this ., these scientists actually want black holes to appear and will go to the extremes to get em.. relying on a theory of hawkings radiation theory (from mid 1970s) thats says micro black holes will only excist for very short time..
well bet your life on it? well thats ok if willing too scientists we all know how u go to extremes in the name of science. but dont bet my life and everybody elses,, and specially dont bet the whole world on it ., im not that interested about the start of the universe if it means an experiment like this.. im sure everyone agrees.. cant we just wait for better safer tecnology than smashing atoms!

what most of you out there proberly dont know is there are 85 nations ready to have a go on this toy,, each with there own experiments of who knows what.,for years to come just to frieghting to think about., and there are plans in the near future (if there is one) to make this thing bigger and even more powerful..
also a thought,., why has usa money gone into this too but not built in there country,obviously they dont trust it. and why is it built underground if its surpose to be safe?

This LHC is not like any other partical/atom smasher it is far more dangerous and powerful
These experiment just arnt worth it. . i think its been everybodies dread that some day scientist will try this kind of dangerous experiment like this i cant beleive our goverments of 10 yrs ago surported this and our goverments of today are still going along with it., and the law ,where is the human rights this is the biggest human right violation ever to exist. its threating our very existance ,, and what for just abit of knowlage? goverments and law dont let these scientist blind u with equations and telling u its safe.,, its obviously not safe to mess with these most dangerous forces of nature.in the universe.
KICK OFF THIS WEDSDAY 10 TH SEPTEMBER., THEY SWITCH IT ON .,800AM someone stop this!

fully accept very high energy subatomic particles do occur in nature (although their frequency of occurrence isn’t very high, (by high I mean we don’t seen billions of very high energy particles per square micrometre every nano second, but the occasional few definitely do occur, however they are lone particles).

However, we will have high concentrations of high energy particles in the LHC *in a very small space*

I am going to play devils advocate for a moment, but in the interests of scientific debate, (of which critical evaluation is a vital part), we need to consider what is possible within the LHC.

One thing I’m very interested about is the kinds of group particles collision interactions that are possible.

For example, imagine two cars driving head on into each other while both are travelling at say 100 Mph … and you get to see the collision in slow motion video from a side on (say 10 metres away) perspective. Now imagine watching the video as the two cars first start to crush and crumple up into each other, as they get squashed together and torn apart by the collision. Now imagine as these two cars are mostly though the process of crushing together and getting torn apart, that a 3rd car then slams into the back of one of the cars. (Or another two car collision occurs at the side of them and their debris is spraying into each other debris).

If this was a particle accelerator and the cars were particles, then the detectors would most likely pick-up an interesting (but less frequently occurring) collision.

The frequency of this kind of group interaction is less than simpler two particle collisions, however its not impossible. So you end up with showers of debris and occasionally we my see something very interesting in the debris. That “something very interesting” event could be caused by these kinds of rarely occurring types of group collisions. And don’t forget that the extra (3rd or more) “cars” don’t need to hit the first two “cars” … their debris can hit other debris etc..

So what if something dangerous was formed in one of these rare showers of group collisions?

Also the whole point of particle accelerators is the beams are designed to focus into a small an area as possible, to maximise the chances of collisions. That works for single collisions, but what about group collisions?

Also Hawking radiation is not 100% proven as fact … its still currently a theory and holes in that theory have been already suggested.

Also the lifespan of a black hole is very likely to be dependent upon its mass, which means a group collision is very likely to exist for longer than a simple collision

A rare group collision merger only needs to exist long enough for it to impact onto some solid part of the machine, for us to be in a potentially very dangerous situation. We are then left hoping that as it impacts, it cannot merge with any else. But if it can merge, then we have the risk of a self-sustaining reaction of continuing mergers, regardless of even if Hawking radiation is proven correct.

Group collision mergers have not been considered for the LHC and we cannot predict with 100% safety all possible interactions.

A particle accelerator is in some ways a blunt instrument when it comes to controlling the exact interactions. We cannot prevent group collision mergers and at ever greater energies, group collision mergers are likely to become more common and more varied.

One point: the pp CoM frame of LHC is at rest on the Earth’s rest frame, but what makes black holes are not protons, but quarks or gluons. And the CoM of a parton-parton collision is NOT at rest. To find a CoM which moves at small speeds -say, smaller than the earth’s escape velocity of 11 km/s- you’d have to sift through tens of thousands of collisions.

Cheers,
T.

Tell them that there are perfectly good astrophysical models for gamma ray bursts.

So there are reasonably concise answers about vacuum bubbles and about mini black holes and strangelets. But I still don’t know what to tell somebody who reminds me that we register several gamma ray bursts a week and worries that some of them may be triggered by high energy collisions.

No, the argument is correct as stated. If such a bubble had been nucleated within the visible universe [ie. our past light-cone] we would be destroyed, which means we wouldn’t be blogging. The fact that we’re blogging about this, then means that “such vacuum bubbles have not been produced anywhere in the visible Universe” [ie. our past light cone].
Since there have been astronomical numbers of collisions at LHC energies in the visible universe [ie. our past light cone], and since NONE of them have produced a bubble that ate us, one can only conclude that collisions at LHC energies DON’T produce universe-eating bubbles…

The page that I gave you to link through to download the LSAG document, is a summary for the general public. If you are confused by the language in the non-technical summary, you should download the full LSAG document and read the appropriate sections, plus the references contained therein.

You could summarize the astrophysical argument like this: yes, bad stuff produced by cosmic rays hitting Earth might just fly through it, but there are much denser bodies around, like neutron stars, and those would capture such collision products. Since they are still around, there is no bad stuff to capture.

The skeptic could still ask if we really know enough about the lifetime of neutron stars (actually measured, not just predicted) to make the argument tight, and again point to gamma ray bursts as possible, naturally occurring disasters triggered by high energy collisions.

One thing which I don’t like about the CERN page which you linked to (http://environmental-impact.web.cern.ch/environmental-impact/en/
LHCSafety/LHCSafety-en.html) is the short section on “vacuum bubbles”.

If we live in a metastable vacuum and a vacuum of a more stable (lower lying) vacuum is nucleated within it, the bubble will expand. The general scenario is that the expansion accelerates to the speed of light within a microphysical time, so you would actually never see the bubble wall coming at you: by the time you see it, it hits you and you die. So I’m afraid the argument which ends that section (“Since such vacuum bubbles have not been produced anywhere in the visible Universe, they will not be made by the LHC”) is just plain wrong.

“If you can provide good, concise answers to that you will have made a pretty solid case, I think.”

That case has already been made in great detail by the LHC Safety Assessment Group [LSAG]. Theirs is the second report in a 5 year span commissioned by CERN to assess the safety of the LHC. The report is summarized at:

[http://environmental-impact.web.cern.ch/environmental-impact/en/
LHCSafety/LHCSafety-en.html]

If you click on the link in the last paragraph at the bottom of the page you can download the entire report for yourself. Also at the same place there are links to 4 other independent reports evaluating LHC safety.

Finally as background to the LSAG report there are the detailed studies by Giddings and Mangano:

Astrophysical implications of hypothetical stable TeV-scale black holes.
Steven B. Giddings (UC, Santa Barbara) , Michelangelo L. Mangano (CERN) . CERN-PH-TH-2008-025, Jun 2008. 96pp.
Published in Phys.Rev.D78:035009,2008.
e-Print: arXiv:0806.3381 [hep-ph]

Comments on claimed risk from metastable black holes.
Steven B. Giddings, Michelangelo L. Mangano . Aug 2008. 3pp. Temporary entry
e-Print: arXiv:0808.4087 [hep-ph]