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Published online 9 February 2009 |
Nature
| doi:10.1038/news.2009.90
Updated online: 9 February 2009
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LHC faces further delay
Collisions won't come before November.
Those waiting for the world's most powerful particle accelerator to start work will have to wait a little longer. An official announcement expected within days is likely to say that the Large Hadron Collider (LHC) will not begin providing data until November — more than a year after its planned start date.
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Yes ... "We could be lucky for a change." Has anyone at Naturenews yet noticed the "off by a factor of 1000" in the Casadio/Harms/Fabi paper? That's right, this paper: http://arxiv.org/abs/0901.2948 ... the paper we're all supposed to be soooo reassured by. The paper with the sentence, "Based on this analysis, we argue against the possibility of catastrophic black hole growth at the LHC." Kindly go to the very first page, and look at the last line before "II. BLACK HOLE DECAY". Look at where it equates the energy-equivalent of a TeV to 1.8 * 10^-27 kg. Oh, my. 1.8 * 10^-27 kg is the energy-equivalent for a giga-electron-volt. A tera is 1000 giga. It should be 1.8 * 10^-24 . A question for the physicists reading this: What is the density of egg-distribution on faces? Should be measurable. The legions of keyboard-pounding pontificators who have been rolling their eyes with disgust at the idea of how anybody, *anybody*, could dare question the wisdom of all these eminent, careful, brilliant scientists, or the glory and beauty of their powerful, wonderful collider! You know, if there were going to be a disaster, this _is_ how it would look, in the months leading up to an irremediable occurrence. The complacent majority, sitting around breathing each other's fumes and patting themselves on the back, and (as we see!) all just blithely accepting -- doing no checking themselves -- that it's all gonna be just fine, and having a great time laughing at the people who are trying to advocate caution in the face of such an irreversible unknown. Just imagine the sneering ... the snickering ... the eye-rolling ... the spitting, the disdain ... that would have greeted someone trying to warn people as they boarded the Titanic. "The bulkheads are not air-tight - they are open, at the top! If you hit an iceberg and breach more than two of the major compartments, the ship will sink!" What words would go flying back .... "Shut up, you fool! As if this ship would hit an iceberg! Icebergs drift in the water, essentially stationary compared to a ship! This ship can dodge any iceberg, idiot! And the ship is piloted by eminent, experienced officers! Shut up! You're frightening my wife! You're frightening my children!" The person who tried to issue the warning would soon be lying on the wharf with two black eyes, two broken arms, and a cracked skull. 10^-24, ladies and gentlemen. Check it out.
To put Walter Gross' mind at ease... Walter, there are high energy protons striking the atmosphere everyday with far higher energies. We haven't been consumed by any black holes created from this process. No further explanation is required. Kelly Banco
@Walter Gross I'm only a graduate Biochemist with an A at A-level in Physics but Walter, surely there's a bigger issue than that: 1 GeV/c2 ? 1.8×10?27 kg but in the paper, apparently units of eV are equatable with units of kg!? "1TeV (? 1.8 · 10?27 kg)" doesn't seem to make any sense to me. Surely units of kg = eV m-2 s2 Someone please explain, it's probably just me being ignorant.
last post should read: @Walter Gross I'm only a graduate Biochemist with an A at A-level in Physics but Walter, surely there's a bigger issue than that: 1 GeV/c2 = 1.8×10-27 kg but in the paper, apparently units of eV are equatable with units of kg!? "1TeV (= 1.8 · 10-27 kg)" doesn't seem to make any sense to me. Surely units of kg = eV m-2 s2 Someone please explain, it's probably just me being ignorant.
First, to AJ P: good observation. At the beginning of the paragraph in question, they note that 1 equals c. This is a common notation in particle and cosmological physics in order to simplify the equations. In principle it's just a scale change. In my opinion, the quick way to describe the 'why' is that there are various constants that always appear in certain parts of certain equations. It's known that they are there, and they are accounted for in the calculations, but are temporarily removed to allow the reader to focus more on the 'meat' of the equations. Second, to Walter Gross: if you actually read the article, you'll note that the correct conversion is used, and noted, in every other instance. The error you pointed out was simply a typo, and not a calculation error on their part.
... hmmm ... unexpected failure of a QUALITY CONTROLLED weld; ? hmmm ? and now "two more bad welds in magnets in other sectors" found?; hmmm ?permanently changing repair durations?; hmmm? "You don't want to screw up twice" (quote)?; hmmm ?"Under CERN's compromise plan, the LHC will accelerate its protons to just 5 teraelectronvolts, well below its designed 7 teraelectronvolts" (quote) ? hmmm? a mix-up of Tera and Giga in a scientific report ? hmmm ? I'am just an (interested) layman and basically in favour of the experiment (but I cannot give a technical justification), but isn't all of that REALLY STRANGE - what's REALLY going on??? An experiment at that much lower energies could mean "wasted money" at all? Has the programme already been stopped, but must be "carried on" due to political reasons ? hmmm ????
Walter Gross starts this conversation by imagining Titanic advocates--like collider advocates today--telling us ?it?s all gonna be just fine.? In the very next post Kelly Blanco illustrates Gross?s point by telling us it?s all gonna be just fine because of an analogy between colliders and cosmic rays. Unfortunately, Blanco also illustrates the frequent problems in this debate with assertions that nothing can possibly go wrong. Such assertions typically last only a short time before being outmoded by rapidly developing physics. Blanco did not get the latest memo. He gives us a reason that is already outmoded. The first reason that nothing could go wrong was that black holes creation would require energy beyond the reach of any collider. [1] Shortly after that assertion, and unrelated to the collider controversy, new physics papers appeared in peer-reviewed journals, based on new theory, predicting creation of black holes at colliders. [2],[3]. The next reason that nothing could go wrong was that black holes would dissipate instantly via Hawking radiation. [4] Shortly after that assertion, and unrelated to the collider controversy, new papers appeared in peer-reviewed journals that questioned the fundamental theory underlying Hawking radiation, a radiation that has never been seen. [5],[6] The next reason that nothing could go wrong is the collider/cosmic ray analogy as cited by Blanco. However, Giddings and Mangano agreed that the analogy is not definitive as applied to earth. [7] To save the analogy, they had to apply it to neutron stars and white dwarf stars where conditions are more extreme, perhaps saving the analogy, but also validating the objections of collider critics about the version of the analogy cited by Blanco. This string of questionable assurances that nothing can go wrong raises the question of whether physics in this area is mature enough to be able to produce definitive safety factors with adequate reliability to protect something as valuable as earth. REFERENCES: [1] W. Busza, R.L. Jaffe, J. Sandweiss, and F. Wilczek; "Review of Speculative ?Disaster Scenarios' Brookhaven, 2000 [2] Steven Giddings and Scott Thomas, "High energy colliders as black hole factories: the end of short-distance physics," Physical Review D 65(5) (2002) 056010. [3] Savas Dimopoulos and Greg Landsberg, "Black holes at the Large Hadron Collider," Physical Review Letters, 87(16) 161602, (2001). [4] J.-P. Blaizot, J. Iliopoulos, J. Madsen, G.G. Ross, P. Sonderegger, and H.-J. Specht, "Study Of Potentially Dangerous Events During Heavy-Ion Collisions At The LHC: Report Of The LHC Safety Study Group" CERN, 2003 (Page 12. In this context ?thermal processes? refers to Hawking radiation.) [5] Adam D. Helfer, "Do black holes radiate?" Reports on Progress in Physics. Vol. 66 No. 6 (2003) pp. 943-1008. [6] William G. Unruh and Ralf Schützhold, "On the Universality of the Hawking Effect," Physics Review D 71(2005) 024028. [7] Steven B. Giddings and Michelangelo M. Mangano , Astrophysical implications of hypothetical stable TeV-scale black holes, Phys.Rev.D (2008) 78:035009