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Notes & Queries 2/9/08

‘Closed time-like curves’ are just the ticket if you want to travel in time. Theoretically, a sufficient distortion of spacetime could make a time machine possible, but Irina Aref’eva and Igor Volovich (Steklov Mathematical Institute, Moscow) take the idea out of the purely theoretical by suggesting that the Large Hadron Collider set to debut this summer at CERN may provide sufficient energy to create a tunnel through time. A tiny tunnel, to be sure, sufficient solely for subatomic particles, but a possible demonstration of wormhole concepts that on a far larger scale could one day prove productive for fast transportation to distant places and remote times.

But as to the argument that the LHC’s operations could establish Year Zero for time travelers (creating the needed first instance of a time machine to which future travelers would be able to return), I’ll take a pass. Surely if massive energies are what it takes to establish such a wormhole (itself a purely theoretical concept, and one that requires yet another theoretical idea — phantom energy — to hold it open), then the universe has supplied us with previous instances of ‘closed time-like curves’ in highly energetic events reaching back to the Big Bang. Does that mean a time traveler could only travel back 13.7 billion years? If so, that’s plenty of temporal territory to play in, but the Fermi question equivalent for time travelers is, where are they?
Every time I run an Enceladus story, another one emerges, this time a demonstration that that on-again, off-again subterranean ocean may actually be there. Or maybe, given the size of the Saturnian moon, we should call it a subterranean ‘lake.’ Cassini team member Jürgen Schmidt (University of Potsdam) and team have been studying the process by which ice particles from the moon’s geysers form and work their way through cracks in the crust to reach the surface. Says Schmidt:

“Since Cassini discovered the water vapor geysers, we’ve all wondered where this water vapor and ice are coming from. Is it from an underground water reservoir or are there some other processes at work? Now, after looking at data from multiple instruments, we can say there probably is water beneath the surface of Enceladus.”

According to Schmidt’s study, an internal lake at a temperature of about 273 degrees Kelvin (O degrees Celsius) is the best way to make sense of what we see coming out of Enceladus’ geysers. The model invokes ice grains condensing in a vent following evaporation from a liquid body of water, consistent with the steady production of ice particles Cassini sees. The possibilities for life within Enceladus seem to shift with every passing paper, but that’s to be expected as we work out a model that multiplies conceivable biospheres in the outer Solar System. The paper is Schmidt et al., “Slow dust in Enceladus’ plume from condensation and wall collisions in tiger stripe fractures,” Nature 451 (February 7, 2008), pp. 685-688 (abstract).
Speaking of outer planet moons, I see that NASA will be running tests on a robotic probe called the Environmentally Non-Disturbing Under-ice Robotic Antarctic Explorer (ENDURANCE) in a few days at Lake Mendota (on the campus of the University of Wisconsin). The long-range goal is to establish whether the autonomous vehicle’s systems might be suitable for operating under the ice of Europa, mapping the local environment and taking samples of microbial life. The plan is to ship the probe to Antarctica for further tests later in the year. All of which takes on growing significance as we work out the huge theoretical question of whether life may not take hold in environments once thought barren, with implications that are obvious for what is going on around other stars.
Orbiting Frog has the 40th Carnival of Space, and while I usually try to point to stories of particular interest for interstellar purposes, the highlight of this week’s carnival may well be the collection of space wallpapers on the Orbiting Frog site itself. Most are simply gorgeous, reminding me that in addition to the beauties of theory, a deeper response to the glories of the cosmos must also include simple awe.

Comments on this entry are closed.

  • James M. Essig February 9, 2008, 18:42

    Hi Paul;

    The mere fact that somehow testing the wormhole hypothesis using the LHC to produce temporally extending wormholes is really fascinating. I have to agree however that the LHC will not be establishing time zero for time travelers. A microscopic wormhole at the sub-atomic particle level is much tinier than a traversable wormhole which would need to be held open by phantom energy. I remember reading that the inward pressure of a human sized inner diameter wormhole would be a whopping approximately 10 EXP 37 tons per square centimeter. Perhaps the problem of producing phantom matter could be solved by more powerful future accelerators or accellerators that produce new and novel reactions with particle species that have not yet been discovered or used in current and previous accellerator experiments. But WOW! 10 EXP 37 tons per square centimeter is a lot. I hear the amount of the phontom matter required to hold the wormhole open as well as the thickness of the phantom matter inner lining goes up sharply for increases in wormhole inner diameter as the inward pressure increases sharply for increases in wormhole inner diameter.

    The phamtom mattergy required to hold the wormhole open would probably be some form of negative mattergy of imaginary mattergy which would have some exceedingly bazaar properties.

    I look forward to posting a comment here on the Enceladus story after I grab myself some dinner.



  • James M. Essig February 10, 2008, 0:08

    Hi Paul;

    I think that there is a very strong probability that aquatic systems potentially capable of supporting life are unbiquitous in our stellar neck of the woods region of the Milky Way on any existent moons that might exist around planets around any of the nearby stars. I would love to have a probe sent to Europa wherein it could melt through the ice to find an ET fish species or similar aquatic organism. The possibility of an IR camera lense comming face to face with such a creature is simply too strong an image for NASA not to try to launch such a mission during the next couple of decades.

    Regarding a sense of deep awe about the unfathimable depths of the potential physically eternal blackness of spacetime, I am so moved when I see photos such as the Hubble Deep Field image, an image of a galaxy, a stellar nebula, that I am moved to the core of my psych. To me, the exploration of the physical cosmos which I think will be an eternal endeavor of our species as I believe it to be such for any ETI species also, is nothing less than a deeply personal as well as a society wide spiritual endeavor. I do not know how to express the awe I feel when I see an image of a nearby galaxy that contains in some cases upwards of a trillion stars. I see such photos and I just have to say to myself in the spirit of Tau Zero, “To The Stars” and feel all the more compelled to do my little part in helping make manned interstellar travel possible.


    Your Friend Jim

  • george scaglione February 10, 2008, 13:04

    jim yes one of the things i myself look forward to most about the LHC is just EXACTLY that kind of thing yes!!!time travel worm holes etc. most certainly we will all benefit from having,at the very “least” our imaginations stretched!! just read a quote from stephen hawking that he credits star trek with that very thing! cool. your friend george

  • dad2059 February 10, 2008, 18:33

    Stephen Baxter and Sir Arthur C. Clarke handled the wormhole mouth problem in The Light of Other Days by the use of the Casimir Force to hold them open long enough to send messages.

    Time travel by material objects wasn’t possible, but observations were, thus no paradox.

    I find this possibility by the LHC to make fact from fiction exciting!

    As for the possible lake under the Enceladan ice, we’ll be pondering that until we send a probe specifically made to find that out. Finding life is frosting on the cake.

  • James M. Essig February 11, 2008, 1:23

    Hi George and dad2059;


    The prospect that we might discover in essense proof that wormholes can and do exist on the subatomic scale by forming such from LHC particle collisions would be for all of us space heads (and I give all of us interstellar travel enthusiasts this name in an effectionate sense) an “I told you so!” moment to those who are not visionary enough thinkers to accept the strong possibility of such entities. The discovery of real macroscopic wormholes would also help vindicate the discontinuous nature of space and time at the Planck levels of space and time which according to some field theories popular in the 60s, 70s, and early 80s is a bubbling seething throth of space time foam with bubbles, arcs, vortices and yes tiny, Planck scale, wormholes comming into and out of being in a causally scrambled and deterministic and adeterministic ramdom manner. I believe that this alleged space time foam supposedly was once in a simillar earlier conception referred to by the word yehlm or another simmilar sounding word, I am not sure which.

    The spacetime foam is accordingly the stuff by which the very fabric of spacetime and mattergy within our universe came into being, even in the blurred time before the first Planck time interval of approximatley 10 EXP – 43 second ticked off.

    If real submicroscopic wormholes can be produced within a particle accellerator, there is no reason to think that virtual or zero point field fluctuations in the form of wormholes are not ubiquitously comming into and out of being as a result of zero point vacuum energy virtual spacetime-mattery fluctuations.


    I would be thrilled if we even learned how to use wormholes even for just the purposes of observation as you define such.

    Regarding the possible lake under the Enceladan ice, I am just waiting for NASA to fund a constellation of interplanetary probes to just about all if not every one of the scores of moon’s within our solar system, several of which might be candidates for some form of life if only in subsurface aquatic or subterreanian environments. Even before we as a civilization are able to embark on manned interstellar space flight to other star systems, we can no doubt have loads of fun exploring each of these numerous moons as we await the development of space craft that will ultimately take us to other star systems.

    Sometimes, part of the fun is in the anticipation of the waiting. Reminds me of the fun I have while driving a thousand miles through senic highway routes to a vacation destination via a long road trip. The short wait time of traveling only intensifies the enjoyment of the vacation. Let’s just hope we can make the wait time for our civilization to reach out for the stars all the shorter.


    Your Friend Jim

  • george scaglione February 12, 2008, 9:48

    dad,yes i have a copy of the light of other days.maybe i should dig it out,lol,i’m sure i wouldn’t have to dig too far.when i really like a book i tend to re read it usually more than once.i keep myself busy,yes. respectfully your friend george

  • ljk February 18, 2008, 14:45


    “Green” robot self-propels through sea

    Thu Feb 7, 2008 5:35 pm EST

    WASHINGTON (Reuters) – A seagoing glider that uses heat energy from the
    ocean to propel itself is the first “green” robot to explore the
    undersea environment, U.S. researchers said on Thursday.

    They said the glider had crisscrossed the 13,000-feet-(4,000-meter-)deep
    Virgin Islands Basin between St. Thomas and St. Croix more than 20 times
    since it was launched in December.

    And it could keep going on its own for another six months, the team at
    the Woods Hole Oceanographic Institution and Webb Research Corporation
    in Falmouth, Massachusetts, predicted.

    “Gliders can be put to work on tasks that humans wouldn’t want to do or
    cannot do because of time and cost concerns,” Dave Fratantoni of Woods
    Hole said. “They can work around the clock in all weather conditions.”

    Such robots can carry sensors to measure temperature, salinity and
    biological productivity.

    They usually surface from time to time to fix their positions using the
    Global Positioning System and to communicate via Iridium satellite to a

    Most gliders rely on battery-powered motors and mechanical pumps, the
    researchers said. This one draws its energy from the differences in
    temperature between warm surface waters and the colder, deeper layers of
    the ocean.

    “We are tapping a virtually unlimited energy source for propulsion,”
    Fratantoni said.

    He said data collected by the glider would help researchers understand
    how eddies in the region affect ocean circulation and move around the
    larvae of fish as well as pollutants.

    (Reporting by Maggie Fox; Editing by Julie Steenhuysen)

  • ljk February 18, 2008, 15:44

    February 18, 2008

    Sandia ceremony to signal reopening of giant Z accelerator

    $90 million refurbishment completed

    ALBUQUERQUE, N.M. — Sandia National Laboratories will formally open the newly refurbished Z machine on Tuesday, Feb.19, at Sandia. Sen. Pete Domenici, R-N.M., and Robert Smolen, deputy administrator for defense programs at the National Nuclear Security Administration, are expected to be in attendance rededication of its premier pulsed power accelerator.

    For the complete news release and downloadable photos, go to


    Sandia media contact: NEAL E. SINGER, NSINGER@sandia.gov, (505)845-7078

  • James M. Essig February 18, 2008, 22:31

    Hi ljk;

    I like the green robot story. It could come in handy for exploring any of the ocean or large deep lake environments on other planetary moons within our solar system. Even the potentially liquid hydrocarbon lakes on Titan might be explored by such machines.



  • Paul Curran February 21, 2008, 9:46

    If something can come back from the future how can we be sure the future does not want to harm us! Physicists in the future may want to experiment with paradoxes involving changing the past in order to study the effects of time travel. To mathematicians we might be no more than labrats.

    Do we really want to be part of that test? The would will change and normal people will begin to turn mad. We will be trapped in a science fiction show we cannot turn off. Consider what will hapen if scientists allow time machine to operate into our time. Be careful Irina Aref’eva and Igor Volovich. Goodluck!

  • ljk February 21, 2008, 9:50

    TIME TRAVEL – IS IT POSSIBLE? (Catalyst: 14/02/2008)


  • ljk February 22, 2008, 0:21

    Propagation of cosmic rays in the foam-like Universe

    Authors: A.A. Kirillov, E.P. Savelova, P.S. Zolotarev

    (Submitted on 21 Feb 2008)

    Abstract: The model of a classical spacetime foam is considered, which consists of static wormholes embedded in Minkowski spacetime. We examine the propagation of particles in such a medium and demonstrate that a single thin ray undergoes a specific damping in the density of particles depending on the traversed path and the distribution of wormholes. The missing particles are scattered around the ray. Wormholes was shown to form DM halos around point-like sources. Therefore, the correlation predicted between the damping and the amount of DM can be used to verify the topological nature of Dark Matter.

    Subjects: Astrophysics (astro-ph)

    Cite as: arXiv:0802.3109v1 [astro-ph]

    Submission history

    From: Alex Kirillov [view email]

    [v1] Thu, 21 Feb 2008 13:50:07 GMT (9kb)


  • ljk February 25, 2008, 10:07

    Dawn of the Large Hadron Collider

    Credit & Copyright: Maximilien Brice, CERN

    Explanation: Why do objects have mass? To help find out, Europe’s CERN has built the Large Hadron Collider (LHC), the most powerful particle accelerator yet created by humans. This May, the LHC is scheduled to start smashing protons into each other with unprecedented impact speeds. The LHC will explore the leading explanation that mass arises from ordinary particles slogging through an otherwise invisible but pervasive field of virtual Higgs particles. Were high energy colliding particles to create real Higgs bosons, the Higgs mechanism for mass creation may be bolstered. LHC will also look for micro black holes, magnetic monopoles, and explore the possibility that every type of fundamental particle we know about has a nearly invisible supersymmetric counterpart. The LHC@Home project will allow anyone with a home computer to help LHC scientists search archived LHC data for these strange beasts. Pictured above, a person stands in front of the huge ATLAS detector, one of six detectors being attached to the LHC.


  • ljk February 26, 2008, 10:07

    Computers take on more than aliens

    They started out scanning the cosmos for signs of extraterrestrial intelligence with SETI@ home. They’ve plotted chess moves, battled malaria, and folded proteins, all from their home computers. Now, volunteers are tackling particle physics with LHC@home.

    It’s one of a number of distributed computing projects that allow you to download scientific data for your computer to analyze when it would otherwise be sleeping. The Search for Extraterrestrial Intelligence launched the first @home project in 1999 with screensaver software that searched for signs of life amid radio signals from space. Today, users can choose from more than 20 @home options.

    The LHC@home software simulates particles cruising along the Large Hadron Collider ring, currently under construction at CERN, the European particle physics lab in Switzerland. In this case, all that number crunching helps scientists determine how to position the magnets that control the proton beam.

    Since 2004, when LHC@ home hit the Internet, 40,000 users have registered, logging in from more than 100 countries. Combined, they have put in 3000 years’ worth of computer time. But they’re still hungry for more data.

    “We have very eager users who want to be running their computers red-hot 24/7,” says Alex Owen, manager of the project, which recently moved from CERN to Queen Mary, University of London.

    To feed the volunteers’ voracious appetites, Owen and co-manager Neasan O’Neill plan two new projects for LHC@home in early 2008. The Garfield program will test drift chambers, and Rivet will compare online data warehouses with newer data sets.

    Users can also organize into teams and compete for top ranking. SwissTeam.net holds the lead with nearly 5.5 million “credits”—a measure of CPU power donated to LHC@home.

    Team founder Dominique Bugmann, an IT specialist in Baden, Switzerland, manages more than 100 computers running LHC@home and other distributed computing projects.

    “One of the great things about LHC@home is that what we do directly helps the scientists,” Bugmann says. “I can help the world just by running software on some PCs.”


  • ljk March 28, 2008, 9:19

    Ignorance and stupidity strike again:


    MSNBC Cosmic Log Mar. 27, 2008


    The builders of CERN’s Large Hadron
    Collider are being sued in federal
    court over fears that the experiment
    might create globe-gobbling black
    holes or never-before-seen strains
    of matter that would destroy the
    planet. The doomsday scenarios
    include runaway microscopic black
    holes, strangelets, and magnetic…


  • george scaglione March 28, 2008, 13:29

    ljk,yes sir ignorance and stupidity strike again! but i’ll bet you this is only a brew ha ha that wont really amount to much! we hope anyhow! almost funny when you think about it!?? your friend george ps yeah i’ve worried about alot of things in my life that amounted to nothing and to me buddy,this “smells” like one of them! ;) g

  • ljk April 4, 2008, 18:10



    Technology has changed in the 400 years since Cervantes first told the story of Don Quixote. Windmills are now particle accelerators and the knight’s lance is a federal court injunction, but the plot is the same. It begins with a befuddled lawyer in Hawaii named Walter Wagner. Having read far too much science fiction as a youth, Wagner fantasizes that he is a physicist by virtue of an undergraduate biology degree with a minor in physics. Accompanied by Sancho, his loyal TA, Wagner embarks on an adventure to slay the Large Hadron Collider (LHC), a doomsday machine that he believes is posed to destroy the world by creating a black hole.

    He seems to have forgotten the last time he tried this. In 1999 Wagner warned that RHIC, the Relativistic Heavy Ion Collider at Brookhaven National Laboratory, must be slain lest it create a black hole (WN 23 Jul 99) . The then BNL director, Jack Marburger, named a distinguished panel of physicists to investigate. Their report noted that nature has been conducting the relevant safety test for billions of years by colliding heavy-ion cosmic rays with the moon. It concluded that creation of a black hole is “effectively ruled out by the persistence of the Moon.”

  • ljk April 10, 2008, 9:43


    There are claims that the world is in peril from a giant particle accelerator.
    Dr Karl looks at the chances of us all being sucked into a black hole of our own making.


  • ljk April 10, 2008, 23:18

    Testing quantum gravity at the LHC

    If extra dimensions exist, quantum gravity could alter the rate of
    well-known reactions


  • ljk April 15, 2008, 9:02

    Gauging a Collider’s Odds of Creating a Black Hole

    New York Times April 15, 2008

    Some experts say too much hype and
    not enough candor on the part of
    scientists about the promises and
    perils of what they do could
    boomerang into a public relations
    disaster for science, opening the
    door for charlatans and demagogues.
    Some in the public have fears about
    the Large Hadron Collider, centering
    on about creating black holes or…


  • ljk May 22, 2008, 10:19

    Bottling the Big Bang

    From the Engineer Online, May 19, 2008

    The air of anticipation around CERN, the European Organisation for Nuclear Research near Geneva, is palpable. In a matter of weeks, the world’s most powerful particle accelerator, the Large Hadron Collider (LHC), will start operating, hurling subatomic particles around its 27km circumference at almost the speed of light. Two months later, the two contra-rotating beams will be squeezed, focused and aimed at each other to collide with colossal force, creating conditions that existed millionths of a second after the Big Bang.

    The physics goals of the LHC are mind-boggling. Discovering the Higgs boson, the particle that explains the origins of mass; explaining why the universe is made of matter not anti-matter; freeing the constituent parts of the particles that make up the nuclei of atoms; possibly making minute black holes which, in passing, would indicate that alternate dimensions exist. But in order to answer these questions, equally mind-blowing engineering has been brought into play, 100m below the ground in the tunnels and caverns that make up the LHC complex.

    Read more here:


  • ljk May 30, 2008, 12:32

    LHC ready by June, says Aymar

    Robert Aymar, the director-general of CERN, has said that
    the Large Hadron Collider will be in “working order” by the
    end of June…


  • ljk June 23, 2008, 10:48

    More evidence that the Large Hadron Collider won’t destroy
    our planet. How boring.


  • Adam June 23, 2008, 16:34

    Dammit Larry! How about some GOOD news?

    I wanted to make mini planet-gobbling black-holes to convert objects into luminous bodies, but this trashes that idea ;-)

  • ljk June 23, 2008, 23:48

    I said it was boring. :^)

    Ever read Einstein’s Bridge by John Cramer?

  • ljk July 2, 2008, 16:20

    As LHC Draws Nigh, Nobelists Outline Dreams–And Nightmares

    Run-up to activation of world’s biggest science experiment later
    this summer

    Scientific American


    By JR Minkel

    July 2, 2008

    The number 14 turns up conspicuously in discussions of the Large
    Hadron Collider (LHC), the soon-to-be world’s biggest particle
    accelerator. Construction of its underground, 17-mile (27-kilometer)
    ring on a site near Geneva, Switzerland, has taken 14 years. It is
    designed to reach energies of 14 tera- (trillion) electron volts
    (TeV), or about seven times that of the Tevatron, the world’s currently
    reigning accelerator at Fermi National Accelerator Laboratory in Illinois.

    And project leaders at the European Organization for Nuclear
    Research (CERN) announced today that next month workers should
    be done chilling the machine’s 50,000 tons of magnets to temperatures
    colder than deep space—a bracing –456.3 degrees Fahrenheit
    (1.9 kelvins)—making them ready to whip opposing beams of
    protons to near light speed and collide them so researchers can
    pick over the debris….

    Needless to say, switching on the largest, most complex science
    experiment ever constructed will be a drawn-out process….

    In anticipation of the start-up, CERN convened a panel of five Nobel
    Prize-winning physicists to give their thoughts on the project….

    who shared the 2006 Nobel Prize in Physics for mapping the faint
    cosmic microwave background radiation that gave evidence of the
    big bang, mentioned the prospect of finding signs of extra
    dimensions of space implied by string theory.

    “I have really high hopes–perhaps too high,” he said….

    The bottom line, Smoot said: “We’re all looking for this to be a
    revolutionary situation, and no matter what comes out, it will tell
    us something.”

  • ljk August 14, 2008, 22:40

    LHC sees first protons

    World’s most powerful particle collider passes major milestone
    towards September switch-on


  • ljk September 10, 2008, 20:56

    Heavy Ion Physics at the LHC

    Authors: P. Giubellino

    (Submitted on 5 Sep 2008)

    Abstract: The first Pb-Pb collisions at the LHC are little more than a year away. This paper discusses some of the exciting measurements which the experiments will be able to perform in the very first run, even with modest luminosity, and gives a very short overview of some of the most interesting ones attainable with more extended runs.

    The dedicated Heavy-Ion experiment ALICE, but also ATLAS and CMS, experiments optimized for p-p collisions, are ready and eager to make best use of the nuclear beams in the LHC as soon as they will be available. The main specificities of the three detectors for Heavy-Ion collisions will also be briefly addressed in this paper. I will try to show that already the first results obtainable with Heavy-Ion beams at the LHC will qualify it as a discovery machine, capable to provide fundamental new insight to our knowledge of high-density QCD matter.

    Comments: Invited talk at the Hadron Collider Physics Symposium (HCP2008), Galena, Illinois, USA, May 27-31, 2008; 9 pages, .docx file

    Subjects: Nuclear Experiment (nucl-ex)

    Cite as: arXiv:0809.1062v1 [nucl-ex]

    Submission history

    From: Paolo Giubellino [view email]

    [v1] Fri, 5 Sep 2008 16:43:38 GMT (439kb,X)


  • ljk September 11, 2008, 23:59

    Mission complete for LHC team

    Proton beams circulate in both directions in two ‘golden hours’


    Home run complete, LHC set to repeat it backwards

    ‘Start up’ day goes smoother than most expected


    LHC milestone day gets off to fast start

    CERN “switches on” seminal collider at 09:30 CET and makes a full
    circulation of the beam within an hour


  • ljk September 22, 2008, 10:34

    Astrophysical implications of hypothetical stable TeV-scale black holes

    Authors: Steven B. Giddings, Michelangelo M. Mangano

    (Submitted on 20 Jun 2008)

    Abstract: We analyze macroscopic effects of TeV-scale black holes, such as could possibly be produced at the LHC, in what is regarded as an extremely hypothetical scenario in which they are stable and, if trapped inside Earth, begin to accrete matter.

    We examine a wide variety of TeV-scale gravity scenarios, basing the resulting accretion models on first-principles, basic, and well-tested physical laws. These scenarios fall into two classes, depending on whether accretion could have any macroscopic effect on the Earth at times shorter than the Sun’s natural lifetime.

    We argue that cases with such effect at shorter times than the solar lifetime are ruled out, since in these scenarios black holes produced by cosmic rays impinging on much denser white dwarfs and neutron stars would then catalyze their decay on timescales incompatible with their known lifetimes. We also comment on relevant lifetimes for astronomical objects that capture primordial black holes.

    In short, this study finds no basis for concerns that TeV-scale black holes from the LHC could pose a risk to Earth on time scales shorter than the Earth’s natural lifetime. Indeed, conservative arguments based on detailed calculations and the best-available scientific knowledge, including solid astronomical data, conclude, from multiple perspectives, that there is no risk of any significance whatsoever from such black holes.

    Subjects: High Energy Physics – Phenomenology (hep-ph); Astrophysics (astro-ph); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics – Experiment (hep-ex); High Energy Physics – Theory (hep-th)

    Report number: CERN-PH-TH/2008-025

    Cite as: arXiv:0806.3381v1 [hep-ph]

    Submission history

    From: Michelangelo Mangano [view email]

    [v1] Fri, 20 Jun 2008 12:57:24 GMT (222kb,D)


  • ljk September 26, 2008, 23:03

    Anders Sandberg: Does the recent LHC breakdown prove quantum immortality?

    Monday, September 22, 2008

    Before you read this post you might want to brush up on the whole quantum immortality argument.

    Okay, you know how the Large Hadron Collider had to be shut down because of of a helium leak? Well, what if this is evidence that we’re about to witness a successive chain of events that will result in the LHC never having the opportunity to destroy the Earth as we know it?

    It’s a classic case of anthropic principle meets the Many World Hypothesis. We can’t observe our non-existence; we can only observe our ongoing existence, no matter how improbable or absurd.

    Full item here:


  • aldo lazzarini September 27, 2008, 20:48

    I heavily recognize that this magnificent experiment would contribute enormously to still profoundly know something more abut our nature.
    Also I think if it were a simply NON it might put things in line because the argument of this work issues from theories such as the Standard Model of Salam, Weinberg and Glashow .
    Thus a very NON really does not mean wrongdoing it is simply a result.
    There have been others historic NON results such as Michelson-Morley and Eötvös among others.
    Their results undoubtedly bent all of our scientific trajectory.

  • aldo lazzarini September 27, 2008, 20:51

    Whatever be the result it will be also useful for next generarions.

  • ljk January 27, 2009, 11:30

    On the Possibility of Catastrophic Black Hole Growth in the Warped Brane-World Scenario at the LHC

    Authors: Roberto Casadio, Sergio Fabi, Benjamin Harms

    (Submitted on 19 Jan 2009)

    Abstract: In this paper we present the results of our analysis of the growth and decay of black holes possibly produced at the Large Hadron Collider, based on our previous study of black holes in the context of the warped brane-world scenario.

    The black hole mass accretion and decay is obtained as a function of time, and the maximum black hole mass is obtained as a function of a critical mass parameter. The latter occurs in our expression for the luminosity and is related to the size of extra-dimensional corrections to Newton’s law of gravitation.

    Based on this analysis, we argue against the possibility of catastrophic black hole growth at the LHC.

    Comments: 8 pages, 4 figures

    Subjects: High Energy Physics – Phenomenology (hep-ph); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics – Theory (hep-th)

    Cite as: arXiv:0901.2948v1 [hep-ph]

    Submission history

    From: Benjamin C. Harms [view email]

    [v1] Mon, 19 Jan 2009 22:41:30 GMT (251kb)


  • ljk January 28, 2009, 14:02

    How do we know the Large Hadron Collider really is safe?

    New Scientist Physics & Math – Jan. 27, 2009


    A new analysis by researchers at the Future of Humanity Institute at the University of Oxford paper on the risks associated with extremely rare but potentially catastrophic events finds that the estimated probability of a “dangerous event” (such as annihilation of Earth by creating a tiny
    black hole) at the Large Hadron Collider of around 10^9…


  • ljk February 10, 2009, 10:26

    LHC’s restart delayed to September, 2009:


  • ljk March 3, 2009, 17:26


    The LHC’s dodgy dossier?

    March 2, 2009 | by KFC |

    There’s no reason to worry about the Large Hadron Collider that is due to to be switched on later this year for the second time. The chances of it creating a planet-swallowing black hole are tiny. Hardly worth mentioning really.

    But last month, Roberto Casadio at the Universita di Bologna in Italy and a few pals told us that the LHC could make black holes that will hang around for minutes rather than microseconds. And they were rather less certain about the possibility they the black holes could grow to catastrophic size. Far from being utterly impossible, they said merely that this outcome didn’t “seem” possible.

    This blog complained that that was hardly the categorical assurance we’d come to expect from the particle physics community. The post generated many comments, my favourite being that we shouldn’t worry because of the Many Worlds Interpretation of quantum mechanics. If the LHC does create Earth-destroying black holes, we could only survive in a universe in which the accelerator broke down.

    Thanks to Slashdot, the story got a good airing with more than few people pointing out that we need better assurances than this.

    Now we can rest easy. Casadio and co have changed their minds. In a second version of the paper, they’ve removed all mention of the black hole lifetime being many minutes (”>> 1sec” in mathematical terms) and they’ve changed their conclusion too. It now reads: “the growth of black holes to catastrophic size is not possible.”

    What to make of this? On the one hand, these papers are preprints. They’re early drafts submitted for peer review so that small problems and errors can be ironed out before publication. We should expect changes as papers are updated.

    On the other, we depend on the conclusions of scientific papers for properly argued assurances that the LHC is safe. If those conclusions can be rewritten for public relations reasons rather than scientific merit, what value should we place on them?

    Either way, we now know that a few minutes work on a wordprocessor makes the LHC entirely safe.

    Ref: http://arxiv.org/abs/0901.2948: On the Possibility of Catastrophic Black Hole Growth in the Warped Brane-World Scenario at the LHC version 2

    Thanks to Cap’n Rusty for pointing out the new version

  • ljk May 14, 2009, 13:19


    The Large Hadron Collider has sparked the imaginations of many. According to Dr Karl, some tales, like the one about mini black holes, is a case of many of us being sucked in.


    See photos from Dr Karl’s trek through Spain and follow his progress on Twitter:


  • ljk June 23, 2009, 21:28

    And for those who may have questions regarding particle physics as
    depicted in the recent film Angels and Demons, check out this Web site
    where real scientists talk about the reality behind the Hollywood here:


  • ljk August 13, 2009, 10:57

    Collider Physics and Cosmology

    Authors: Jonathan L. Feng

    (Submitted on 8 Jan 2008 (v1), last revised 12 Jul 2008 (this version, v2))

    Abstract: In the coming year, the Large Hadron Collider will begin colliding protons at energies nearly an order of magnitude beyond the current frontier. The LHC will, of course, provide unprecedented opportunities to discover new particle physics.

    Less well-known, however, is that the LHC may also provide insights about gravity and the early universe. I review some of these connections, focusing on the topics of dark matter and dark energy, and highlight outstanding prospects for breakthroughs at the interface of particle physics and cosmology.

    Comments: 14 pages, plenary talk presented at the 18th International Conference on General Relativity and Gravitation (GRG18) and the 7th Edoardo Amaldi Conference on Gravitational Waves (Amaldi7), Sydney, Australia, 8-14 July 2007; published version

    Subjects: General Relativity and Quantum Cosmology (gr-qc); Cosmology and Extragalactic Astrophysics (astro-ph.CO); High Energy Physics – Experiment (hep-ex)

    Journal reference: Class.Quant.Grav.25:114003,2008

    DOI: 10.1088/0264-9381/25/11/114003

    Report number: UCI-TR-2008-2

    Cite as: arXiv:0801.1334v2 [gr-qc]

    Submission history

    From: Jonathan Feng [view email]

    [v1] Tue, 8 Jan 2008 23:36:03 GMT (727kb)

    [v2] Sat, 12 Jul 2008 18:25:17 GMT (854kb)