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Tags large hadron collider , lhc

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Old 25th May 2009, 12:06 PM   #1
MattusMaximus
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Large Hadron Collider feedback needed

Howdy all,

I know there are many professional physicists here, and some who even work on the LHC (Cuddles, for one). I wanted to get some feedback from you concerning a recent blog post I made and the subsequent commentary...

LHC Lunacy & Doomsday Scenarios

This guy has come into my commentary thread and started to spew some real nonsense, in my opinion. His website - LHCfacts.org - also seems to be full of woo. What I need is for some people more well versed in particle physics than me to read through that commentary thread at my blog post and see if my criticisms are valid. I want to make sure that I'm on the right track with my comments.

Any other feedback regarding this topic would also be appreciated. Thanks in advance!

Cheers - MM
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Old 25th May 2009, 12:32 PM   #2
sol invictus
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Well, I'm afraid JTankers is actually correct about the relativistic speeds issue. The LHC is designed so that the two counter-rotating beams carry the same energy. In other words the protons in each beam have equal but opposite velocity when they collide, at least on average. (The reason you want that is that otherwise the products of the collision would always fly off in one direction and you'd lose most of them out the end of the detector. There are actually some colliders designed asymmetrically like that intentionally, but not the LHC.)

If a "black hole" was produced by a proton-proton collision at the LHC, it would be at rest at least on average (I haven't calculated how likely it would be that it has more than escape velocity, but I expect that in a reasonably large fraction of events it will not). On the other hand if a BH was produced by a cosmic ray collision, it would initially have a large velocity in the earth's frame. Of course that doesn't mean it would keep that large velocity after it was produced - it would be likely to pass through the earth, for one thing.

The best argument against these nutjobs is that there is absolutely no reason to think there is a danger. The theories that predict "black holes" will be produced are extremely speculative - and they also predict that they will evaporate immediately. There is no theory that predicts black holes will be produced and be a danger.

I put "black hole" in quotes because in those theories, the things that would be produced behave nothing like large black holes. They are unstable states of a few particles that are very temporarily held together by gravity before they fly apart again. They're resonances, not stable objects.

If we don't turn on the LHC because of these unwarranted fears, by the same standard we should stop doing all science experiments. There is always an inherent risk in doing things you've never done before. But there is a much bigger risk in not doing them.

Last edited by sol invictus; 25th May 2009 at 12:36 PM.
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Old 25th May 2009, 12:51 PM   #3
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Originally Posted by sol invictus View Post
Well, I'm afraid JTankers is actually correct about the relativistic speeds issue. The LHC is designed so that the two counter-rotating beams carry the same energy. In other words the protons in each beam have equal but opposite velocity when they collide, at least on average.
That'd be correct for an electron-positron collider; the beam momenta cancel out and a created-at-threshhold product would really be at rest. However, the LHC is a proton-proton collider; you should really think of it as a quark-quark collider (or a quark-gluon or gluon-gluon collider) with the proton as sort of a sabot. The proton-proton momenta are balanced but, due to the proton form factor, the individual collisions are wildly imbalanced, and the collision products usually have a huge velocity along the beam axis. The probability of a collision product ending up at rest with respect to the Earth, i.e. below 11 km/s, is very small.
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Old 25th May 2009, 01:34 PM   #4
sol invictus
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Originally Posted by ben m View Post
That'd be correct for an electron-positron collider; the beam momenta cancel out and a created-at-threshhold product would really be at rest. However, the LHC is a proton-proton collider; you should really think of it as a quark-quark collider (or a quark-gluon or gluon-gluon collider) with the proton as sort of a sabot. The proton-proton momenta are balanced but, due to the proton form factor, the individual collisions are wildly imbalanced, and the collision products usually have a huge velocity along the beam axis. The probability of a collision product ending up at rest with respect to the Earth, i.e. below 11 km/s, is very small.
Yes, I'm aware of that - that's why I said on average (which makes it very different from the cosmic ray case).

I haven't calculated that probability - or more importantly, the expected number of trapped BHs produced after some time. But I don't agree with you that it's necessarily very small. It's going to depend on the model, and one should take into account that the black hole can end up trapped even if its velocity is initially greater than escape velocity (for example if it goes down into the earth and slows down).

But regardless, there is no reason to think about this except for fun, because there is no reason to think this can happen.
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Old 25th May 2009, 01:37 PM   #5
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Originally Posted by ben m View Post
That'd be correct for an electron-positron collider; the beam momenta cancel out and a created-at-threshhold product would really be at rest. However, the LHC is a proton-proton collider; you should really think of it as a quark-quark collider (or a quark-gluon or gluon-gluon collider) with the proton as sort of a sabot. The proton-proton momenta are balanced but, due to the proton form factor, the individual collisions are wildly imbalanced, and the collision products usually have a huge velocity along the beam axis. The probability of a collision product ending up at rest with respect to the Earth, i.e. below 11 km/s, is very small.
Okay, this confirms part of what I was thinking. If the products of these collisions were at rest, then why do we surround the collision point with so many detectors to capture the products? He makes it sound like these products are just going to float there, which makes no sense given the huge level of energy going into the collision.

I do realize that I may have been too quick with my response to JTankers on the relative velocity issue, but it seemed to me that he was making it sound like the collisions involved weren't relativistic at all, which is nutty.

I don't really even know what point he's trying to make with this argument. My guess is that he is talking about a micro-BH being produced in the beam collision, which - according to him - would then be at rest wrt Earth, so it would then pose a danger because it would suck up everything in sight. He's being very vague, but I think that is the gist of his argument.
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Old 25th May 2009, 01:44 PM   #6
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Originally Posted by sol invictus View Post
Well, I'm afraid JTankers is actually correct about the relativistic speeds issue. The LHC is designed so that the two counter-rotating beams carry the same energy. In other words the protons in each beam have equal but opposite velocity when they collide, at least on average. (The reason you want that is that otherwise the products of the collision would always fly off in one direction and you'd lose most of them out the end of the detector. There are actually some colliders designed asymmetrically like that intentionally, but not the LHC.)
Are there other particle accelerators that operate in this manner?

Quote:
If a "black hole" was produced by a proton-proton collision at the LHC, it would be at rest at least on average (I haven't calculated how likely it would be that it has more than escape velocity, but I expect that in a reasonably large fraction of events it will not). On the other hand if a BH was produced by a cosmic ray collision, it would initially have a large velocity in the earth's frame. Of course that doesn't mean it would keep that large velocity after it was produced - it would be likely to pass through the earth, for one thing.
I understand that, which is why I kept bringing up to him my point about naturally produced muons. Btw, why exactly would a mBH pass through the Earth in the case of a natural cosmic ray event?

Quote:
The best argument against these nutjobs is that there is absolutely no reason to think there is a danger. The theories that predict "black holes" will be produced are extremely speculative - and they also predict that they will evaporate immediately. There is no theory that predicts black holes will be produced and be a danger.
Ah yes, I have thought about this point before - the Hawking radiation will make the lifetime of the BH very brief. Yet he seems to be implying that there will be some danger due to this Hawking radiation, and he hasn't addressed my question on why he thinks this.

Quote:
I put "black hole" in quotes because in those theories, the things that would be produced behave nothing like large black holes. They are unstable states of a few particles that are very temporarily held together by gravity before they fly apart again. They're resonances, not stable objects.
So that's different than Hawking radiation, I presume?

Quote:
If we don't turn on the LHC because of these unwarranted fears, by the same standard we should stop doing all science experiments. There is always an inherent risk in doing things you've never done before. But there is a much bigger risk in not doing them.
Yup, hence my comment about the paralyzing precautionary principle.
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Old 25th May 2009, 02:05 PM   #7
sol invictus
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Originally Posted by MattusMaximus View Post
Are there other particle accelerators that operate in this manner?
Yeah - B factories (at least some of them - Ben can probably fill that in). Those are electron-positron colliders that produce B-mesons. You want the B to drift a little in a particular direction before decaying, so its decay location is displaced from the collision location.

Quote:
I understand that, which is why I kept bringing up to him my point about naturally produced muons. Btw, why exactly would a mBH pass through the Earth in the case of a natural cosmic ray event?
It wouldn't - it would decay. But in some hypothetical world where it didn't decay, it might have a small cross-section, in which case it could pass right through the earth without interacting.

Quote:
Ah yes, I have thought about this point before - the Hawking radiation will make the lifetime of the BH very brief. Yet he seems to be implying that there will be some danger due to this Hawking radiation, and he hasn't addressed my question on why he thinks this.
That's certainly nonsense. All it can Hawking radiate into are particles with lower energy, and those are produced anyway at colliders. And it can't produce any more energy than went into it in the first place.

Quote:
So that's different than Hawking radiation, I presume?
Well, the fact is you can't really treat this as Hawking radiation from an ordinary black hole because the state we're talking about is so short-lived. But that just means it will behave somewhat more like a conventional particle interaction and somewhat less like a black hole.

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Old 25th May 2009, 02:20 PM   #8
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If the super small black hole did get captured by the earth, and didn't decay, it would be the ruin of us all...

...in about 3 billion years.

http://scienceblogs.com/startswithab...es_and_you.php

Seriously would a black hole that small, if it existed, even "eat" a proton? Or would it just sail right through it?
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Old 25th May 2009, 02:25 PM   #9
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Thanks for that link, TI. It is revealing to see that JTankers has shown up in the commentary section there as well.
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Old 25th May 2009, 02:34 PM   #10
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Lol so he did! And he missed the point completely.
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Old 25th May 2009, 03:15 PM   #11
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Originally Posted by sol invictus View Post
I haven't calculated that probability - or more importantly, the expected number of trapped BHs produced after some time. But I don't agree with you that it's necessarily very small.
Giddings & Mangano put it at 10^-3 to 10^-4.
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Old 25th May 2009, 03:33 PM   #12
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Originally Posted by sol invictus View Post
Yeah - B factories (at least some of them - Ben can probably fill that in). Those are electron-positron colliders that produce B-mesons. You want the B to drift a little in a particular direction before decaying, so its decay location is displaced from the collision location.
BaBar at SLAC certainly has assymetric beams. And HERA at DESY, though this was a proton-(1st gen) lepton collider and not a B-factory.
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Old 25th May 2009, 03:37 PM   #13
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Originally Posted by sol invictus View Post
If a "black hole" was produced by a proton-proton collision at the LHC, it would be at rest at least on average (I haven't calculated how likely it would be that it has more than escape velocity, but I expect that in a reasonably large fraction of events it will not). On the other hand if a BH was produced by a cosmic ray collision, it would initially have a large velocity in the earth's frame. Of course that doesn't mean it would keep that large velocity after it was produced - it would be likely to pass through the earth, for one thing.
This may sound silly, but in the 4.5 billion year history of the Earth, is it not quite likely we've had head on collisions between cosmic rays with very similar energies? I know the chances of this happening in any given collision is tiny... but 4.5 billion years is a long time.
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Old 25th May 2009, 05:08 PM   #14
sol invictus
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Originally Posted by ben m View Post
Giddings & Mangano put it at 10^-3 to 10^-4.
OK, I see. But it looks (Fig. 12) like for some parameter ranges, the total number of trapped holes can be >10,000.

Originally Posted by Tubbythin View Post
This may sound silly, but in the 4.5 billion year history of the Earth, is it not quite likely we've had head on collisions between cosmic rays with very similar energies? I know the chances of this happening in any given collision is tiny... but 4.5 billion years is a long time.
It's not silly. I think the idea is that holes produced by those collisions would have enough energy to fly through the earth without interacting, whereas holes produced in the collider could (in principle) be gravitationally trapped.

But of course what really happens is they all evaporate immediately, so the whole thing is nonsense.
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Old 25th May 2009, 05:59 PM   #15
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Originally Posted by ben m View Post
Giddings & Mangano put it at 10^-3 to 10^-4.
Wow, that looks like a great paper (linky). I'll have to read through it - thanks for mentioning it!

Btw, it seems that JTankers has run off from my blog. After I brought some of the points made here to bear (as well as mentioning the calculation that TI linked to), he left this cryptic comment...

Quote:
I primarily limit my current activities to correcting mis-information (the same goal as your site coincidentally).

Thanks again for the conversation,
Jim
Oh, teh irony!
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Old 28th May 2009, 03:42 AM   #16
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The Collider Debate

There is a well-developed debate on the collider issue. Most confidently-asserted safety factors have exceptions. Respectable albeit speculative theories enable trouble. The speculative aspect means that the probability of trouble may be low, but expected value (probability times value if the probability is actualized, the standard metric of decision theory) is high because the cost of trouble-in this case destruction of earth-is 6.7 billion lives, to say nothing of future lives.
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Posts here mention Hawking radiation as a safety factor. Most physicists are confident that Hawking radiation will work, but it has never been seen, and physics papers have been published that question the fundamental theory behind Hawking radiation. [William G. Unruh and Ralf Schützhold, "On the Universality of the Hawking Effect," Physics Review D 71(2005) 024028.], [Adam D. Helfer, "Do black holes radiate?" Reports on Progress in Physics. Vol. 66 No. 6 (2003) pp. 943-1008.]
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An analogy between collider-created black holes and cosmic-ray-created black holes is supposed to demonstrate safety. The argument is as follows: Cosmic rays have been hitting earth with energy in the collider range for billions of years. If collider-created black holes are dangerous, then cosmic-ray created black holes should be dangerous too. The fact that we are still here demonstrates that they are not. However, the analogy is not precise. Because of the asymmetry in momentum between the cosmic ray and the earth particle it hits, cosmic-ray-created black holes will always be moving at high velocity in the rest frame of earth. If they accrete slowly, and if they are uncharged, as some theories predict, they will zip right through earth like a neutrino. A very small number of neutrinos stop in earth. However, if a fast black hole hits something, it will only accrete, slow a bit, and continue. It would have to accrete many particles to slow below escape velocity. The binomial probability that any will accrete enough to slow below escape velocity, even in trillions of trials over four billion years, is still vanishingly small. On the other hand, the Large Hadron Collider is designed with beams of equal energy, energy that cancels out when particles collide. Someone mentioned the point that the energy will rarely cancel out precisely. Quarks, the colliding particle of consequence for black hole creation, have large random energy. Greg Landsberg calculated that only about 0.00001 of collider-created black holes would be moving at less than escape velocity from earth. However, since he predicts that the LHC will produce a black hole per second, that still results in 315 per year moving at less than escape velocity. Some of these will orbit within earth, and have forever to accrete. The speed of accretion depends on the accretion model; with some models accretion takes forever, other models allow fast accretion. Giddings and Mangano, collider supporters, in a paper cited by other posters here, recognize that the collider/cosmic ray analogy is not definitive when considering conditions on earth. They had to extend it to consider conditions on neutron stars and white dwarf stars, which (they claim) should be able to trap even cosmic-ray created black holes, making the lifetimes of neutron stars and white dwarfs shorter (if BHs are dangerous) than apparently observed. However, several scientists have put forth somewhat speculative theories to dispute this.
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This website is named for James Randi, a magician who supported the Committee for the Scientific Investigation of Claims of the Paranormal (CSICOP) by showing how some fraudsters worked their tricks. My father, who was both an engineer and a magician, knew Randi. This is relevant since Skeptical Inquirer, the magazine of CSICOP, published an article “Doomsday Fears at RHIC” [by Thomas Gutierrez in the May 2000 issue] (RHIC, the Relativistic Heavy Ion Collider, started at Brookhaven in 2000.) Richard Posner says Gutierrez “implies incorrectly that only irresponsible journalists raised fears . . .” [Posner, Catastrophe, p 274.] The safety factor at the time was the impossibility of black hole production at colliders. Gutierrez claimed that a black hole was as likely to form randomly as at RHIC. Gutierrez was not the only one to make this claim. A Brookhaven paper claimed that black hole production required energy beyond reach of any collider. [W. Busza, R.L. Jaffe, J. Sandweiss, and F. Wilczek; "Review of Speculative ‘Disaster Scenarios' Brookhaven, 2000] The interesting thing about these claims is that shortly afterward string theorists began to predict black hole production at colliders. (If their somewhat speculative theories are true.) Hawking radiation and the collider/cosmic ray analogy as applied to earth were other confidently-asserted safety factors that also proved inadequate, as discussed above. This raises the question of whether science in this area is mature enough to produce adequate safety factors. Toby Ord of the Future of Humanity Institute at Oxford says that the low probabilities of collider trouble asserted by some scientists are inaccurate because the probability that the scientific theory on which those probabilities are based is wrong is higher than the low probabilities asserted. [Toby Ord, Rafaela Hillerbrand and Anders Sandberg, Probing the Improbable: Methodological Challenges for Risks with Low Probabilities and High Stakes] (For the probability that a scientific theory is wrong, they consider things like the frequency of retractions in scientific journals.)
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Since the probability of trouble seems low, it seems unlikely that the collider will destroy us. However, it seems hubristic and immoral to risk the lives of billions when that risk is only “unlikely.” Individuals regularly take risks of 1 in 1,000. Subjecting earth to that risk has an expected value of 6.7 million lives lost, a number in the Hitler range. Of course the actual result is either zero or 6.7 BILLION lives lost; the mathematics of subjective value say that this risk is “worth” 6.7 million lives. This is only an example. I am not claiming this level of risk for colliders. Estimate your own subjective probability considering the existing safety factors. Given the poor record for collider safety factors, any reasonable estimate results in a large number here.
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Old 28th May 2009, 04:07 AM   #17
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Originally Posted by James Blodgett View Post
Individuals regularly take risks of 1 in 1,000. Subjecting earth to that risk has an expected value of 6.7 million lives lost, a number in the Hitler range. Of course the actual result is either zero or 6.7 BILLION lives lost; the mathematics of subjective value say that this risk is “worth” 6.7 million lives. This is only an example. I am not claiming this level of risk for colliders. Estimate your own subjective probability considering the existing safety factors. Given the poor record for collider safety factors, any reasonable estimate results in a large number here.
So you seem to pluck the number is 1 in 1000 out of thin air. Then use it to make an argument that the LHC = bad. The admit that you plucked the number from thin air. What is the point of this paragraph^ then? What if I pluck a number from thin air. Say 1 in 10000000000000000000000000000000000000000000000000 00000000000. Now is the LHC too big a risk?
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Old 28th May 2009, 04:52 AM   #18
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Welcome to the forum James Blodgett.
You may have missed the post with the link to this blog entry: The LHC, Black Holes and You. It explores the consequences of a stable micro-black hole being generated.
Given the assumptions of
  • The LHC energies are high enough to explore extra dimensions that allow the creation of micro-black holes.
  • Hawking radiation does not exist so that black holes with a mass of 2.5 x 10^-20 grams do not evaporate in a time of ~10^-84 seconds.
Then how long would it take the black hole to consume the Earth?
It turns out that it takes three trillion years for a classical (described in 3D) black hole to get to 1 kilogram in mass.

The Steven B. Giddings, Michelangelo M. Mangano paper Astrophysical implications of hypothetical stable TeV-scale black holes has more calculations for higher dimensions and other stellar objects. They find that the lifetime of white dwarf stars makes the scale billions of years.
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Old 28th May 2009, 05:35 AM   #19
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The black hole won't even consume another atom, much less the earth. Why? Basically because there are atoms, and not just a continuum of matter for it to worm through.

For a start, if you did create such a micro-black hole from 2 protons, it would inherit the electrical charge of 2 protons. I.e., electrically it would act like a nucleus of Helium. It would probably even get one or two electrons and be the weirdest atom in history.

Gravity is the weakest force at that scale, so it's safe to say that it would repulse other nuclei electrically long before they got close enough to be gobbled by gravity and increase the black hole.

But assumptions have no place in science, of course, so let's calculate how close _is_ "close enough" for such a black hole. What is the distance at which anything going in, can't come out? That's called the Schwarzschild radius.

The simplest way to calculate it is, pretty much: 3km for a mass equal to our Sun, and it varies linearly with mass from there. For something the mass of the whole Earth, it would be 9mm, btw.

So how large a black hole would particle collision produce? The mass of two neutrons? (Protons and neutrons are roughly the same mass.) There? Five? (Including the energy of the collision turned into mass, not just the two particles.)

A neutron weighs 1.67492729x10^-27 kg. So 5 of them is very approximately 8x10^-27 kg. Ok, let's say 6-7 neutrons then, so we have a neat 10^-26 Kg.The Sun weighs 1.9891×10^30 kg, let's say 2x10^30 kg.

So we'd have basically, in metres: 3km * mass_of_micro_blackhole / mass_of_sun 3*10^3 * 10^-26 / 2*20^30 = approx 1.5 * 10^-53 metres. Ok, let's make it a bit heavier. About the mass of 9-10 neutrons gets us close enough for comfort to a neat 10 to the power -53 metres. I repeat: ten to the power minus fifty-three.

By comparison a helium atom has a radius of 31 picometres, or approx 3x10^-11 metres.

The resulting black hole would be _infinitesimally_ smaller than a real helium atom. To actually gobble such an atom (therefore starting the process of increasing its size), you'd have to shoot it right inside the nucleus you want it to swallow. We're talking about incredible energies to just get another atom gobbled up.

Plus, the whole thing would be smaller than a Planck length (1.6 * 10^-35 metres), so it's just impossible. In fact, we're talking something as ridiculously small as to be 10^18 times smaller than a Planck length. We're talking something a billion billion times smaller than a Planck length.

Note that increasing the mass of the black hole even a thousand times, a million times, a billion times, or a trillion times (really really strong accelerator), would still leave you with a ridiculously infinitesimal size.

But _if_:

- it was actually possible

- the LHC could actually create it

- there was no such thing as Hawking radiation

... nothing bad would happen anyway. It would capture two electrons and survive for ever as the world's weirdest helium atom.
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Old 28th May 2009, 06:05 AM   #20
sol invictus
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Originally Posted by James Blodgett View Post
The speculative aspect means that the probability of trouble may be low, but expected value (probability times value if the probability is actualized, the standard metric of decision theory) is high because the cost of trouble-in this case destruction of earth-is 6.7 billion lives, to say nothing of future lives.
Biology research is dangerous. People study live viruses, bacteria, perform genetic engineering. Smallpox is kept alive in labs. Chemistry is dangerous - ever read Ice 9? All science is inherently dangerous, because all science involves studying the unknown.

High energy physics is by far the best understood of all those disciplines. We know very, very well what is possible and what is not. As I've said before, there is no theory in which LHC "black holes" are dangerous. To invent one, you have to discard several fundamental facts about the world and ignore cosmic rays. If you did the same for biology or chemistry (or other kinds of physics, for that matter) you'd arrive at a deadly risk far sooner. It makes as much sense to worry that it might open the gates to hell.

So if the cranks succeed in stopping the LHC on these absurdities (they won't), where will they stop? If they manage to stop all science, guess what - we're all dead for sure. The human race as a whole faces major existential threats we are quite certain are real - global warming, diminishing fossil fuel supplies, epidemics. The risk of not turning on the LHC is much, much greater than the risk of turning it on.

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Old 28th May 2009, 06:11 AM   #21
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Originally Posted by James Blodgett View Post
There is a well-developed debate on the collider issue.
No there isn't. There's real scientists and there's a bunch of cranks crying that the sky is going to fall. Sadly, I think the real scientists have been rather misguided on this issue in feeling that they need to produce some pretence at a risk assessment and actually argue the issue with the cranks. It would have been better for everyone if we'd all just ignored them from the start instead of coming up with a meaningless small probability that just gives people the chance to say "But it's not zero, therefore you're evil and we're all going to die.".
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Old 28th May 2009, 07:03 AM   #22
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In any case, if this were able to destroy the Universe, Cosmic Rays, which have MUCH higher energies sometimes, would have done so billions of years ago.
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Old 28th May 2009, 10:58 AM   #23
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Originally Posted by James Blodgett View Post
Most confidently-asserted safety factors have exceptions.
Two comments.

One, this was a thread on the LHC. You cited a ten-year-old paper demonstrating the safety of RHIC. These are different things with different parameters.

Second, saying "safety factors have exceptions" ignores---well, many things about safety factors generally and everything about this particular safety factor. If you read the relevant papers on the safety factors (Busza Jaffe and Sandweiss for RHIC, Giddings and Mangano for LHC) you will notice that they do NOT rely on trusting any sort of collider physics predictions. Instead, they rely on the one sort of safety estimate that does not have exceptions: "We have done exactly this experiment a gazillion times already".
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Old 28th May 2009, 05:05 PM   #24
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Originally Posted by HansMustermann View Post
For a start, if you did create such a micro-black hole from 2 protons, it would inherit the electrical charge of 2 protons.
Don't they usually smash together more than just 2 protons (not that that makes any difference to the rest of what you say)?

Originally Posted by HansMustermann View Post
... nothing bad would happen anyway. It would capture two electrons and survive for ever as the world's weirdest helium atom.
That's awesome!
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Old 28th May 2009, 05:07 PM   #25
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Originally Posted by sol invictus View Post
The human race as a whole faces major existential threats we are quite certain are real - global warming, diminishing fossil fuel supplies, epidemics. The risk of not turning on the LHC is much, much greater than the risk of turning it on.
Fossil fuels!? Dear god man, don't you realize that every time you drill a well you might be unleashing the demon horde???
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Old 28th May 2009, 05:37 PM   #26
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Originally Posted by temporalillusion View Post
Don't they usually smash together more than just 2 protons (not that that makes any difference to the rest of what you say)?
They shoot whole beams of them, but that's because it's so unlikely that any two will actually collide. Just like outer space, it's basically mostly empty space in there. And these things repel each other too, so they have to be coming pretty head on or it won't count.

What they're trying to do is the equivalent, if you will, of trying to study what happens when two 5.56mm bullets hit head-on in mid air. By shooting from two different points that are about a mile away from each other. If you just shoot one from each side, it's not going to happen. You put some belt-fed SAWs there, if you want to actually find any pair that smacked into each other.

The probability that three or more will collide in a big pile-up is even slimmer.

Not that it matters that much. As you've noticed, you could increase that mass by a billion and you'd still be a billion times short of the universe's resolution. (And even more trillions of trillions of trillions of times shorter than it'll ever bounce to another charged particle.)

To use a messed up metaphor, the whole micro-black-hole claim is a bit like saying that if you draw a pentagram and light black candles and sail "hail satanas" three times, a secret message will appear in this text that will cause insanity in any who read it. Only it will be a billionth of a billionth the width or height of a pixel on the monitor. Surely you can see why it's not going to do much, or why even if I were wrong by a factor of one billion, hey, it's still not going to do much
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Old 28th May 2009, 06:17 PM   #27
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There is actually some buzz in the science press about a theory that ALL particles are really tiny black holes.
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Old 28th May 2009, 06:39 PM   #28
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Folks, you should all realize that James Blodgett is JTankers, the guy who posted his pseudoscientific comments on my blog and the Science Blog entry that TI referenced earlier. I know this because on my blog JTankers links to a website called LHCfacts.org, and guess who writes that blog... James Blodgett
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Old 28th May 2009, 07:08 PM   #29
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Originally Posted by Cuddles View Post
No there isn't. There's real scientists and there's a bunch of cranks crying that the sky is going to fall. Sadly, I think the real scientists have been rather misguided on this issue in feeling that they need to produce some pretence at a risk assessment and actually argue the issue with the cranks. It would have been better for everyone if we'd all just ignored them from the start instead of coming up with a meaningless small probability that just gives people the chance to say "But it's not zero, therefore you're evil and we're all going to die.".
Heh. Did you see the guy on the Daily Show who said that the possiblity of a catastrophe was 50%? After all, either it will happen, or it won't happen. Therefore, 50%.

John Oliver's reply was "I don't think probability works like that..."
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Old 28th May 2009, 07:15 PM   #30
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Originally Posted by MattusMaximus View Post
Folks, you should all realize that James Blodgett is JTankers, the guy who posted his pseudoscientific comments on my blog and the Science Blog entry that TI referenced earlier. I know this because on my blog JTankers links to a website called LHCfacts.org, and guess who writes that blog... James Blodgett
Yeah, I think we pretty much worked that out out for ourselves...
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Old 28th May 2009, 07:26 PM   #31
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Originally Posted by HansMustermann View Post
They shoot whole beams of them, but that's because it's so unlikely that any two will actually collide. Just like outer space, it's basically mostly empty space in there. And these things repel each other too, so they have to be coming pretty head on or it won't count.
Ah good point.
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Old 28th May 2009, 09:37 PM   #32
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MattusMaximus claims that I and James Tankersley are the same person. Now, that is a charming if nutto conspiracy theory. Fortunately, there is an easy way to demonstrate it wrong, based on something you can all look up on the Internet.
-
First, go the American Mensa website. You will have to look it up on Google. I tried to post the URL, but this website has an anti-spam engine that prevents that for newbies to prevent spam that redirects to commercial websites. On the left side of the page, under “quick links,” click on “annual gathering.” Then, near the top of the page, click on “playlist.” You will find a list of presentations by date and time. Scroll down to the following listing:
-
Friday, July 3
3:00 PM - 4:00 PM
The Intellectual Challenge of Global Risk Reduction
by James Blodgett , James Tankersley , Win Wenger
--------------------------------------------------------------------------------
There are several risks that, if actualized, could make the human race extinct. The adequacy of our collective methods of dealing with these risks varies from risk to risk. In some cases we are doing what we can. In other cases denial, frustration, and hubris detract from effective response. Clear, creative thinking improves our response and improves our odds. We can contribute to clear thinking. Even a small reduction in a global risk is a substantial contribution. At this presentation we will discuss various risks, contributions we have made, contributions we would like to make, and ways you can help.
-
The point is, we are both scheduled to present together. If we/I were the same person, we would need the gift of bi-location, a psi power that should win Randi’s million dollar challenge. Anyone here who happens to be attending the Annual Gathering is welcome to attend this presentation, meet both of us together, and check both of our ID. If you would like to contribute a million dollars to the cause, that would be welcome also.
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Old 28th May 2009, 09:41 PM   #33
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James Blodgett, your refutal of the Cosmic Ray proof is hilariously flawed.

There is a ZERO asymmetry between the particles because of relativity. You have to analyze all this in terms of relativistic frames. When you do that, the conditions are precisely similar.
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Old 29th May 2009, 04:56 AM   #34
sol invictus
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Originally Posted by James Blodgett View Post
MattusMaximus claims that I and James Tankersley are the same person. Now, that is a charming if nutto conspiracy theory.
How can it be a "conspiracy theory" to claim two people are the same? If the theory is correct, who would they conspire with?
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Old 29th May 2009, 05:38 AM   #35
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Originally Posted by James Blodgett View Post
The point is, we are both scheduled to present together. If we/I were the same person, we would need the gift of bi-location
No, you'd need that if you were presenting in different places. If you're both the same person, being in the same place at the same time really shouldn't present much of a problem.
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Old 29th May 2009, 05:54 AM   #36
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Originally Posted by James Blodgett View Post
There are several risks that, if actualized, could make the human race extinct. The adequacy of our collective methods of dealing with these risks varies from risk to risk. In some cases we are doing what we can. In other cases denial, frustration, and hubris detract from effective response. Clear, creative thinking improves our response and improves our odds. We can contribute to clear thinking. Even a small reduction in a global risk is a substantial contribution. At this presentation we will discuss various risks, contributions we have made, contributions we would like to make, and ways you can help.
This is nothing but meaningless drivel in the context of the LHC.

Your comments would be equaly applicable to the dangers of the destruction of the earth due to a scheduled demolition to make room for an interstellar bypass.
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Old 29th May 2009, 06:32 AM   #37
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Here's my theory. There are no natural black holes. They all started from aliens with LHCs.

Discuss.


(and by Discuss I mean Ignore)
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Old 29th May 2009, 07:35 AM   #38
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Originally Posted by Cuddles View Post
No, you'd need that if you were presenting in different places. If you're both the same person, being in the same place at the same time really shouldn't present much of a problem.
Pauli disagrees with you. Unless they have opposite spins.
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Old 29th May 2009, 07:38 AM   #39
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Originally Posted by James Blodgett View Post
MattusMaximus claims that I and James Tankersley are the same person.
Oh, my mistake.
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Old 29th May 2009, 07:56 AM   #40
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Originally Posted by Evilgiraffe View Post
Pauli disagrees with you. Unless they have opposite spins.
ALL I see is spin.
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