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Large Hadron Collider feedback needed

sol invictus said:
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.
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In "Moving Mars", or some such book, I think they suggested a black hole would have to be about 1cm in diameter before it would be able to absorb matter faster than it got bled away with Hawking radiation or whatever it is.

Hence the LHC, creating such on the order of subatomic particles, would be nothing to worry about. I presume the book got real numbers from physicists.
 
At times I think the collider opponents have been playing "Half Life" for too long.....
 
James Blodgett mentions Rössler in his postings.

FYI:
Otto Rössler is a theoretical biochemist. He has produced a couple of what looks like unpublished and non-peer reviewed papers on black holes and the LHC, e.g. Abraham-Solution to Schwarzschild Metric Implies That CERN Miniblack Holes Pose a Planetary Risk by O.E. Rössler.

The problems with the papers have been pointed out in
Commentary on two papers by O.E. Roessler on black holes by Gerhard W. Bruhn. Basically Rössler has not understood the difference between t in the Schwarzschild solution and the local time for an observer.

Rössler has a cryptic reply here that does not actually address the issues (it may be a problem with his English).
 
Only somewhat tangentially relevant ...

The May 2009 H.E.S.S. Source of the Month is A VHE gamma ray source in the W51 region, which is principally about providing yet more evidence that SNR (supernova remnants) are where at least a significant proportion of the galactic cosmic rays we observe here on Earth come from.

In some ways this is not news - supernova shock waves have been proposed as the sites where galactic cosmic rays are accelerated for many decades now, and a wide variety of observations are consistent with hypotheses based on this - but it provides more direct evidence for the 'if the LHC could produce 'Earth-devouring' BHs, then they should be quite plentiful in the ISM' case.

It might be an interesting exercise to make some OOM estimates of the rate of 'LHC energies and above' collisions that take place in the immediate environs of a young SNR; I expect that the LHC would be utterly wimpy by comparison ...

ETA: and SNR themselves are real wimps when compared to an energetic AGN jet (the terminations of some of these - in the IGM! - are relatively easily detected in the optical waveband!!).
 
Beerina said:
In "Moving Mars", or some such book, I think they suggested a black hole would have to be about 1cm in diameter before it would be able to absorb matter faster than it got bled away with Hawking radiation or whatever it is.

Hence the LHC, creating such on the order of subatomic particles, would be nothing to worry about. I presume the book got real numbers from physicists.
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Not really on topic, but related to the point about many cranks not understanding the real numbers, is something I learned while at that FermiLab tour this past weekend.

FermiLab creates anti-protons in order to smash them together with protons in two counter-rotating beams in the Tevatron (a similar mode of operation to the LHC). In order to make one gram of such antimatter (enough to be "dangerous" as in Angels & Demons, for instance), FermiLab would have to work constantly for many, many millions of years because when they do make it, it's in such small amounts.

Update: Since my most recent posts, its been a couple of more days since FermiLab has been operating the Tevatron at TeV levels, and there still aren't any planet-eating mBHs killing us all. Just sayin' ;)
 
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James Blodgett said:
Rainer Plaga should be considered here. He is a real astrophysicist, and he provides all the math you guys could want. See http://arxiv.org/abs/0808.1415v2 .
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What about the charge? If (like the mass) it evaporates even slightly more slowly than in a normal BH, this is ruled out immediately by cosmic ray collisions with the earth's atmosphere.

There are several papers debunking Plaga's analysis in great detail, including one by Giddings and Mangano and another by the authors of the model he used.
 
James Blodgett said:
Rainer Plaga should be considered here. He is a real astrophysicist, and he provides all the math you guys could want. See http://arxiv.org/abs/0808.1415v2 .

Plaga is not only Ph.D., but also Dr. Habil within the German system.
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Why do you keep ignoring the fact that FermiLab's Tevatron has already been operating at TeV levels in a similar manner to the proposed operation of the LHC, and there has been no generation of planet-eating mBHs? 20+ years of continuous operation and we're still here.

Plaga's paper and your arguments be damned - the data disagree with you. Find another hobby.
 
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BenBurch said:
He hasn't understood a word of that paper. He just knows what other paranoids have told him it means.
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I'm not even talking about the paper. I'm simply talking about the fact that what he's afraid of has already been happening for 20+ years, and he cannot get it into his head that no mBHs which are going to destroy the planet have been created in that entire time... because... we're... still... here.

JB's cognitive dissonance is astonishing.
 
Oh, and the RHC. Lets not forget that. If you think there is something magical about the p-p-bar interaction that keeps MBHs from forming, Brookhaven has been doing 500 GEV hadron work for a while now.

Last I heard, New York is still there.
 
Several people have made the point that current colliders are similar to the LHC.

However, they also say that the LHC will be seven times more powerful than current colliders. (I thought it was more than that, so your point has some value in convincing me. What metric are you using, for what type of collisions?) The reason for being of the LHC is that it explores things that have not been seen. So an analogy between previous colliders and the LHC is not precise.

Since accretion is supposed to be slow, previous colliders might have already created a black hole. Particle detectors might not see it if it is uncharged. I don’t worry about that since nothing can be done about it. In some models , colliders create a black hole every ten years or so of operation, so it is possible that current colliders are about to create a black hole. This might be a reason to shut current colliders down. But I don’t think we are likely to have much luck with that case.
 
From the past history of this forum, here is a quote from Sol Invictus:

>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) . . .

When I made the same point, here is what BenBurch said about it:

>James Blodgett, your refutal (sic) 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.

Can we schedule a debate between Sol Invictus and BenBurch?

BenBurch says “And we're NOT real physicists?”

I used to be, and in some ways still am, a fan of science. I used to think that real scientists were better than what I see in this debate, both here and many other places. Now I am sadder but wiser. A loss of faith. Yes, unfortunately, you guys look like real physicists.
 
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