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Supernova….LHC Style

Just when you thought that all your fears about the Large Hadron Collider (LHC) were assuaged now here’s something new to fear that I’ve never even heard of…A Bose-Supernova

(Boy, we’re really milking this LHC stuff aren’t we? The stories just keep pouring out.)

These relatively new fears appear to be related to experiments performed in 2001 by Elizabeth Donley and buddies at JILA in Boulder, Colorado. These experiments used magnetic fields to alter the atomic forces between the atoms in a Bose Einstein Condensate (BEC). This caused the condensate to first implode, then explode in what’s now referred to as a Bose Supernova or bosenova.

–Series of stills of multiple bosenovas–

A recent physics blog post I read had this to say:
“some clever clogs has pointed out that superfluid helium is a BEC and that the LHC is swimming in 700,000 litres of the stuff. Not only that but the entire thing is bathed in some of the most powerful magnetic fields on the planet.”

(I’ve been informed that “clever clogs” = irritatingly smart people)

So if all this is true, then the LHC could create a huge version of one of these bosenovas and turn Geneva into a huge crater, right?

Well…let’s look at some background first.

What exactly is a Bose Einstein Condensate?
A Bose-Einstein Condensate is generally considered to be the 5th state of matter. It’s existence was first proposed by Satyendra Bose and Albert Einstein in the 1920s but it took until 1995 for it to be actually created and therefore proved. It is a gas that has been cooled to billionths of a degree above absolute zero, the so-called nano-kelvin regime. (Why does everything sound cooler with nano in the name?)

Ok, so this is about million times colder than anything else in the universe and just about as cold as anything can get. At this temperature, the atoms are at their lowest possible energy state and are moving pretty slowly. This means that we know their velocity with an extremely high degree of accuracy. Who remembers what the uncertainty principle says about this?……Yes, Timmy, you are correct. The more you know a particle’s momentum the less you can know about its position.

Think of each atom’s position as a fuzzy blob of uncertainty. All the fuzzy blobs in a condensate overlap such that no possible measurement can tell them apart.  Therefore, the positions of all the atoms are smeared together into one super-atom of sorts. That means that all the atoms occupy the same quantum state and they can all be described by just one wave function. This is essentially a quantum object that has been beefed up to macroscopic size, giving us new insights into the quantum world that we wouldn’t otherwise have. Who knows where these condensates might lead? Atom lasers and quantum computers are just the tip of the iceberg I believe.

–Bose Einstein condensates being created–

So, is this a real threat?

Not according to Malcolm Fairbairn and Bob McElrath at CERN:

“We conclude that that there is no physics whatsoever which suggests that Helium could undergo any kind of unforeseen catastrophic explosion,”

I admit, the bosenova scenario happening at the LHC seems a tad more plausible than the LHC creating earth-sucking black holes or strange-matter. There’s much we don’t know about bosenovas (or is it bosenovae?) but it seems clear that for them to occur, a special phenomenon called Feshbach Resonance must happen. This resonance allows magnetic fields to change the atomic interactions which is what causes the explosion. The fact is that this resonance cannot occur with the helium the LHC is using. Therefore, a bosenova will not be created at CERN this spring. End of story.

(yeah, I know…I doubt it too)

4 comments to Supernova….LHC Style

  • I’d blame it on the Bossa Nova and be done with it.

    Couldn’t resist.

  • SimonS

    I don’t think the helium in the LHC is cooled low enough to be a BEC is it? That seems unneccesarily cold for superconductivity- isn’t it at 2K or something? Roughly 7 orders of magnitude too hot.

  • Good question SimonS,

    That specific issue was the biggest problem I had while doing research for this post.

    Apparently, the helium at the LHC can still be technically considered a BEC. This is probably because it reaches its lowest energy state. Other atoms (like rubidium) require nano-kelvin temperatures to become a BEC. This is the temperature range that all the BEC experiments that I’ve read about take place in.

  • What concerns me more is the possibility that bosenova implosions (BEC with attractive interactions) might be potentially capable of causing matter density collapse to “infinite” density (create a micro black hole in the lab).

    A difference of opinion appears to exist on the potential for mBH formation:

    NASA and other speculation for[1][4], MIT papers for[2][5], Prof Huang and Nobel Laureates Dr. Cornell and Dr. Weiman comments against.[6][7][8]

    (Dr. Cornell and Dr. Weiman won the 2001 Nobel prize for Physics for creation of the first BEC[10] and were present when the first bosenova implosion was accidentally created and the mechanics of this event are not fully understood, including explanation for the fraction of atoms that disappeared from the experiment. Some physicists are concerned that low velocity micro black holes should not be created on Earth before the safety of doing so is proven with 100% certainty.)

    The following is a brief chronology of quotes, events and papers from 1996 to 2008:

    1996 John G. Cramer[1] “The BEC is so compact and dense that, with sufficient atoms added, a mini-black hole of atomic size should form. Readers of David Brin’s Earth and Larry Niven’s “Hole Man” should be familiar with some of the implications of this.” “The BEC of Wieman and Cornell contained only a few thousand atoms of rubidium [naturally repelling RB87]. The first BEC is a long way from any danger of black hole formation.”

    2000 Kerson Huang MIT[2] “A black hole opens up at the center, …density fluctuations becomes infinite“ “The density in the black hole shoots up as time goes on, fed by waves of implosion“

    2001 Cornell, Wieman[3] “In the first of these Feshbach resonance experiments our students Jake Roberts, Neil Claussen, and postdoc Simon Cornish suddenly changed the magnetic field to make a negative. We observed that, as expected, the condensate became unstable and “collapsed,” losing a large number of atoms” “Because of its resemblance (on a vastly lower energy scale) to a core collapse supernova, we have named this the “Bosenova.”” “there is no clear explanation of the energy and anisotropy of the atoms in the explosion, the fraction of vanished atoms, and the size of the cold remnant.”

    2002 Science@NASA[4] “Neutron stars and their cousins, white dwarfs and black holes, are extreme forms of matter that many scientists would love to tinker with — if only they could get one in their lab. But how? Researchers experimenting with a new form of matter called Bose-Einstein condensates may have found a way.”

    2008, Feb 1 Eleftheriou, Huang[5] “…local collapse to a state of infinite density.” “We verify that the picture presented by Ueda and Huang is correct. For N > Nc , a “black-hole” does appear at the center of the trap”

    2008, Feb 28 Eric Cornell[6] “Probably not a black hole, more likely they just clumped together into molecules”

    2008, Jun 6 Carl Wieman[7] “I can state ABSOLUTELY CATEGORICALLY that it is totally inconceivable that a black hole could be produced by these phenomena” “In the Bosenova, the BEC is seen to get slightly denser than a regular BEC for a brief time, but it still remains thousands of times less dense than regular air.”

    2008, Jun 9 Eric Cornell[8] “Yes it causes the cloud to shrink a lot, but no, not all the way down to an infinitesimal black hole. ”

    2008, Jun 10 Kerson Huang[9] “There’s no way the ultimate density of the collapsed atoms can be any higher than that of an ordinary solid”

    References:

    [1] http://www.npl.washington.edu/AV/altvw77.html, Bose-Einstein Condensation, A New Form of Matter, Analog Science Fiction & Fact Magazine (Mar 1996)
    [2] http://arxiv.org/PS_cache/cond-mat/pdf/0012/0012418v1.pdf Cold Trapped Atoms: A Mesoscopic System, Kerson Huang, MIT (21 Dec 2000)
    [3] http://nobelprize.org/nobel_prizes/physics/laureates/2001/cornellwieman-lecture.pdf BOSE-EINSTEIN CONDENSATION IN A DILUTE GAS; THE FIRST 70 YEARS AND SOME RECENT EXPERIMENTS, Nobel Lecture, Cornell, Wieman (8 Dec 2001)
    [4] http://cua.mit.edu/ketterle_group/Press/My_pet_neutron_star_4-02.pdf, My Pet Neutron Star, Science@NASA (3 Apr 2002)
    [5] http://arxiv.org/PS_cache/cond-mat/pdf/9908/9908229v1.pdf Instability of a Bose-Einstein Condensate with Attractive Interaction, Eleftheriou & Huang, MIT (1 Feb 2008)
    [6] http://www.lhcfacts.org/?p=6#comments Email, Dr. Eric Cornell (28 Feb 2008 2008)
    [7] http://www.lhcfacts.org/?p=6#comments Email, Dr. Carl Wieman (6 June 2008)
    [8] http://www.lhcfacts.org/?p=6#comments Email, Dr. Eric Cornell (9 June 2008)
    [9] http://www.lhcfacts.org/?p=6#comments Email, Prof. Kerson Huang (10 June 2008)
    [10] http://www.intute.ac.uk/sciences/spotlight/issue2/bosenova.html Do the Bosenova

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