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LHC surpasses its own record as the world’s most powerful particle accelerator

The views expressed are those of the author and are not necessarily those of Scientific American.


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CERN control roomThe Large Hadron Collider, the so-called big bang machine outside Geneva, has eclipsed its own world record as the highest-energy particle accelerator in history. The collider, commonly known as the LHC, accelerated its twin proton beams to 3.5 trillion electron-volts, or TeV, Friday morning, according to a prepared statement from CERN, the European lab for particle physics that operates the LHC.

In November the collider worked its beams up to 1.18 TeV, breaking the record of 0.98 TeV that had been held by Fermilab’s Tevatron in Illinois. The following month CERN steered those beams—one clockwise, one counterclockwise—into a head-on smashup with a total energy of 2.36 TeV, the highest-energy collision ever seen.

The objective in ramming such high-energy particles together is to probe their makeup and to observe the shower of particle debris that sprays from the collision. The LHC should be sufficiently powerful to probe the energetic first moments of the universe’s evolution after the big bang and may be able to fill in a number of chapters now missing from fundamental physics. Prominently, it could find the Higgs boson, a theoretical particle that imbues other particles with mass; it might also identify the particle culprit that makes up the mysterious galaxy-shaping stuff known as dark matter.

CERN says it will soon announce a timeline for converging the 3.5-TeV beams, which together will yield another record: a collision at 7 TeV. That will be the LHC’s peak collision energy for 18–24 months before the collider shuts down in 2012 for a year of hardware repairs; only after that will CERN fire up the LHC at its design energy of 7 TeV per beam, producing 14-TeV collisions. But given how much physicists have learned from the much weaker Tevatron, even a half-strength LHC may have a chance to open up new realms of physics.

Photo of CERN personnel in the control room during the LHC’s record-breaking run: M. Brice / CERN

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  1. 1. jtdwyer 6:18 pm 03/19/2010

    If the LHC condenses nucleons from a high energy Quark/Gluon plasma it’ll be worth every Euro.

    The rest is fantastic nonsense. Go ahead and hold your breath.

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  2. 2. rbarney 7:54 am 03/20/2010

    Paddy tells it as it is! well done jt

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  3. 3. Dr_HJ 8:35 am 03/20/2010

    No-one has yet considered the possibility that such high energy collisions may result in the undetectable migration of the collision induced sub-atomic particles into other dimensions, rendering the machine useless as an experimental device.

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  4. 4. rbarney 9:12 am 03/20/2010

    Head on collisions ? or glancing blows ? no eye witnesses !
    nobody knows.

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  5. 5. jtdwyer 9:15 am 03/20/2010

    Dr_HJ – My guess is that ‘other dimensions’ exist only as abstract concepts.

    I guessing that the LHC does produce new ‘Generation IV’ fermions (quarks and leptons) – imbued with higher mass than prior generations by the greater energy of the collisions that create them. I expect this because I suspect that the mass attributed to fermions is merely an artifact of the increasing collision velocity producing them and the methods used to determine their mass.

    I suspect that the Higgs boson does not exist and that quantum mass is not a characteristic property of particle matter but a function of its emission energy. Likewise, the particle selection function of the Higgs field can only have been performed by the temporally varying density of the initial universe, which determined the emission energy of particle matter as it was initially produced.

    As for dark matter, please refer to the comment/essay: "Dark Matter as Gravitational Estimation Error" and its subsequent discussion posted with the article at:
    http://www.scientificamerican.com/article.cfm?id=dark-matter-cdms

    But, I’m just guessing.

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  6. 6. dbtinc 10:00 am 03/20/2010

    Pure science at its best – I guess – but to what end? Insert usual blather about the need for basic research no matter what as opposed to spending the money directed at the natural sciences here on earth. Help me understand what the billions spent on that white elephant "lab" in orbit is producing. How many Hubbles could have been launched in its place?

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  7. 7. MAPSJ 11:39 am 03/20/2010

    Go, Go, Go!!!!
    Put the petal to the metal (but carefully, don’t break it).
    Let the fireworks begin!
    This is truely going where humanity has never gone before. We are sure to see some things we expect, and many we don’t.
    Great Work!

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  8. 8. Robert Houston 12:55 am 03/21/2010

    CERN’s LHC is the single most immoral project in history. This is because several serious dangers to the planetary environment that have been presented by outside physicists remain unresolved. These include the potential production of strangelets, micro black holes, and unprecedented global warming. This is in the context of the disintegration of CERN’s past safety arguments regarding cosmic rays and black hole evaporation via Hawking radiation.
    .
    The reckless ramp-up to imminent particle collisions at three times its previous world record demonstrate a level of irresponsibility rarely seen in large-scale science projects. It’s understood that many of the engineers at CERN’s Chamonix meeting wanted to proceed incrementally, but the experimenalists selfishly insisted on rushing ahead.

    Yet, according to a former group leader at the Max Planck Institute for Physics, such high energy collisions at the LHC may generate slow-moving micro black holes emitting Hawking radiation equivalent to "the energy released in a major thermonuclear explosion per second" (Rainer Plaga, Ph.D. at http://arxiv.org/abs/0808.1415v3 – see p. 9).

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  9. 9. RobDegraves 1:08 pm 03/21/2010

    Rainier Plaga’s paper has been answered ages ago here (http://prd.aps.org/abstract/PRD/v80/i8/e084036). His response to the paper was anemic and so far no one has published his paper. In addition, his theory depends on fine tuning the accretion rate to the density of the Earth so that they even out, which would not work on denser bodies. In other words, if his theory was true, the Sun would not exist.
    BTW… Rainier is the only one who is even remotely a physicist amongst the people who claim that the LHC is a danger.

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  10. 10. jtdwyer 5:06 pm 03/21/2010

    Robert Houston – If the engineers recommended a incrementally increasing test runs to maximum velocity it would have been justified by concerns for potential electromechanical equipment failure rather than the worrisome strangelets, micro black holes, dark matter, new big bang or what have you.

    Particle collisions cannot produce more energy than is applied. Much more energetic events have been observed around the universe, requiring the conversion of much more energy. Not to say that we should proceed without caution, since unexpected things do happen, as all competent engineers know.

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  11. 11. Robert Houston 12:11 am 03/22/2010

    Has J.T. Dwyer never heard of nuclear bombs or E=mc2? These contradict his claim that "Particle collisions cannot produce more energy than is applied." Indeed, "much more energetic events" than at the LHC occur "around the universe," including the supernova explosion of mere solar mass stars, which several scientists have hypothesized may be due to LHC-style doomsday machines built by local civilizations (Cf. the Fermi Paradox). Dwyer is correct, however, that any notes of caution by CERN personnel refer exclusively to the welfare of the Machine, never the environment or planet.

    Contrary to the comment by Rob DeGraves, the 3rd version (2009) of Dr. Plaga’s paper provided in an appendix a highly cogent 3-page reply to the 2009 paper by Casadio et al. Plaga concluded that "Casadio et al. correctly and usefully identify the range of a crucial theoretical parameter Mc [critical mass] for which black-hole growth is not catastrophic, but offer no argument of how to exclude that the real Mc lies outside this range."

    Mr. DeGraves’ claim that Dr. Plaga’s "theory depends on fine tuning the accretion rate…" is erroneous. As Plaga wrote on p. 7, "I choose possible and not fine-tuned parameters to study and illustrate the nature of possible risk." Contrary to DeGraves, CERN’s own Giddings and Mangano concluded in 2008 that the density of the Sun and ordinary stars would be insufficient to stop cosmic ray-produced micro black holes. Dr. Adrian Kent, Prof. of Physics at Cambridge, has pointed out, however, that the LHC experiments by generating slow-moving black holes and strangelets could pose a risk to the Sun as well as the Earth.

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  12. 12. jtdwyer 2:10 am 03/22/2010

    Robert Houston – I think my statement reflects E=mc**2, as m is potential energy. I also think that the disintegration of protons has less potential energy that the disintegration of massive atoms, but I’m no expert.

    If there is risk of an explosive event being produced by an experiment, it is the responsibility of physicists. The engineers are responsible for the equipment: the engineers’ recommendations would be limited to equipment considerations. Considering the problems they’ve had with the equipment, I’d expect them to be cautious. Your implication that a cautious recommendation by engineering indicated that the experiment could endanger the universe is unfounded.

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  13. 13. criticnyc 7:07 pm 03/23/2010

    @

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  14. 14. criticnyc 7:20 pm 03/23/2010

    @jtdwyerWhile it is true that the engineers are preoccupied with the machine, the fact remains that their errors and misconceptions demonstrate that responsible and expert human beings can make mistakes even on the largest projects – perhaps especially on the large group projects. This gives us every reason to suppose that the theorists will risk error in their calculations as well, as indeed has already been demonstrated in their incorrect rejoinder to Rainer Plaga’s currently unrefuted paper suggesting great risk. Since the outcome of the higher energy collisions is unknown, and the current theories are merely guesses at hoped for outcomes, it makes sense to have serious review by disinterested outsiders before going ahead, even for the engineers, whose carefully tended machine would be lost anyway in a global catastrophe. It is presumably impossible that the risk be zero if the whole outcome is unpredictable, but it should be minimized by careful review, not abandoned to the adolescent excitement of physicists with a narrow view of the event.

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  15. 15. jtdwyer 7:59 pm 03/23/2010

    criticync – Good assessment, but you do not mention that the risks are also indeterminable, pitting the vested interests of all those involved against a public alarmed by unsubstantiated speculation. It’s a difficult choice…

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  16. 16. Michael Hanlon 9:20 pm 03/23/2010

    Who comes through the cosmic rift that will occur at 10 terravolts of collision force, Howard The Duck or The Dark Overlords?

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  17. 17. criticnyc 11:58 pm 03/23/2010

    @jtdwyer But there is no difficult choice. The risks are indeterminable, but wisdom dictates review by outsiders to assesses what safeguards might be enabled, if any are possible. Rushing ahead lying to the public about perfect safety with obsolete arguments such as Cosmic ray 1 and braying that caution is needless is to launch the galactic Titanic without lifeboats when one plans to navigate icebergs at night with primitive radar.

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  18. 18. jtdwyer 3:04 am 03/24/2010

    criticnyc – But icebergs were a very real risk for the the Titanic. I am highly skeptical of both the highly promoted predicted discoveries and the highly publicized risks imagined. My independent assessment is that the risks and potential impact are not excessive and that some unexpected beneficial discoveries may result. But that’s just my opinion.

    I agree with you that a more independent group of scientists and engineers should assess the risk/benefit of at least initial operational decisions. Given the amount of capital that’s already been sunk into this boondoggle, I doubt anyone could stop its proceeding at this point, without a major earthquake or similar obvious and immediate risk.

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  19. 19. criticnyc 3:31 pm 03/24/2010

    @dwyer – mBHs, strangelets, or nuclear explosions – it doesn’t matter which icebergs it might hit, as long as we cannot predict with certainty which they are and where. We cannot measure the risks of an outcome which is unpredictable. Respectable theorists have predicted the theoretical possibility of catastrophe, but not its risk, for this reason.

    Most experts feel that the risk is small. But this opinion is not based on any physics, but on social psychology – eg it hasn’t happened so far, none of my colleagues are concerned, it is pleasant to be respectable and reasonable, and so on. Such feelings are known to be misleading. In the case of fires, for instance, people get killed because they feel and act in groups, sometimes too slowly.

    The actual physical risk remains unknown, as long as the outcome is unknown. Already we have an unexpected outcome from the first 1.18 TeV round – more kaons than expected, which suggests strangelet production is more likely.

    No one curious as to the outcome and possibly remarkable findings of this unprecedented experiment is happy to delay it but given the behavior of CERN so far (conflicting safety reports, patronizing and misleading public reassurance, huge design flaws) outside reviewers are needed to ensure whatever cautionary measures are possible are taken eg a slow ramp up instead of rushing into 3.5 TeV collisions straight away, as the physicists are set on doing next week (March 30) (though it seems that the beam density of protons will be low at first).

    Since the theoretical possibility of overwhelming disaster hasn’t yet been properly refuted, it would be wrong to rely on "gut instinct", which seems to be the ruling principle so far.

    Can a $9 billion juggernaut be stopped? Unlikely, granted. But not impossible that it be delayed, at least, while outside review is conducted.

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  20. 20. Robert Houston 11:29 pm 03/24/2010

    CERN’s assertion of no risk from the LHC is in obedience to a bureaucratic edict that, in regard to the possibility of disaster, all statements to the public must conclude that "the probability is zero." This was admitted by CERN’s chief science officer Jos Endelin in an interview in the New Yorker ("Crash Course," May 14, 2007).

    Critics of the project are less sanguine. The bleakest assessment is by Luis Sancho, a philosopher of science, who has calculated the risk of eventual catastrophe caused by the LHC as 78% (see: Cerntruth.com/?p=7 ).

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  21. 21. gelunelu 4:05 pm 03/25/2010

    The HLC is dangerous, and incredibly useless.

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  22. 22. NIRVANA 6:11 pm 03/25/2010

    Like we are walking to touch a stone base of the PYRAMID.Although we can fly to look all over by helicopter.Exactly what to be after you do. when we know how we come,what to be,how to go..NIRVANA…..

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  23. 23. jtdwyer 4:07 pm 03/26/2010

    criticnyc – I don’t really disagree, but as a disrespectable theorist I skeptically consider that the theorists are overestimating the potential of their experiment. I could certainly be wrong, and unlike the appearance of a comet in the sky, humanity did have control over and responsibility for this experiment.

    Since I have no influence on any decision regarding whether or how these experiments are to proceed, I can only worry that the sky will implode or cheer exuberently, GO! GO! or hope for the the anticlimax I expect.

    As always, I will hope that we all can survive with minimal suffering.

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  24. 24. morp 5:32 am 06/15/2010

    A cheaper and more quickly result can be obtained by using an analog model.
    Fill a paper bag with water and smash it onto a closed window.
    The result will be a terrific bang inside and many droplets of water outside
    Wen they use E.M. energy they will get short-lived droplets of E.M. energy obeying the Maxwell laws. Like children with a box they hoped to find "something" inside,but the box was empty
    What did the CERN cost since1950 ? What are their results? Nothing .
    Spin-offs?Yes!Contributing to the finance problems of small countries?

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