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Posts Tagged ‘science’

Powerless Haikus

Thursday, April 19th, 2012

Jordan is an English major on a Communications co-op term at TRIUMF. When the power went out at TRIUMF, he was asked to write about what it was like. He decided to write it in haiku. He had never written a haiku before. It showed.

I have never written a haiku before. After the power came on, I Googled haikus and these barely count.  Enjoy.


The power is out

There is nothing left to do

Except write haikus


Computers shut off

I forgot to save my work

Many strong expletives


Eyes raised to the ceiling

A brief respite from the screen

It is sunny out?


A brief argument

On the location of Spain

No one can Google


Two scientists turn

Engage in deep discussion

Or maybe shallow


Silent Meson Hall

Punctuated by a laugh

Cannot find the source


The power is back

I am Googling some haikus

Amateurish, I

– Written by Jordan Pitcher (Communications Assistant)


This is a follow-up from our last post where Paul Schaffer, Head of the Nuclear Medicine Division at TRIUMF, was talking about his experience of being in the media spotlight. In this post, Paul talks more in-depth about the science of medical isotopes.

It all started 19 months ago. A grant that would forever change my perspective of science geared specifically toward innovating a solution for a critical unmet need—in this situation, it was the global isotope crisis. In 2010, not too long out of the private sector, I was already working on an effort funded by NSERC and CIHR through the BC Cancer Agency to establish the feasibility of producing Tc-99m—the world’s most common medical isotope—on a common medical cyclotron. The idea: produce this isotope where it’s needed, on demand, every day, if and when needed. Sounds good, right? The problem is that the world had come to accept what would have seemed impossible just 50 years ago.

The current Tc-99m production cycle, which uses nuclear reactors. Image courtesy of Nordion.

We are currently using a centralized production model for this isotope with just a six hour half-life. This model involves just a handful of dedicated, government-funded research reactors, producing molybdenum-99 from highly enriched uranium (which is another issue for another time). Moly, as we’ve come to affectionately call it, decays via beta emission to technetium, and when packaged into alumina columns, is sterilized, and encased in a hundred pounds of lead. It is then shipped by the thousands to hospitals around the world. The result: the world has come to accept Tc-99m, which is used in 85% of the 20 to 40 million patient scans every year as an isotope available from a small, 100 pound cylinder that was replaced every week or so, without question, without worry. Moly and her daughter were always there…but in 2007 and again in 2009, suddenly they weren’t. The world had come to realize that something must be done.

In the middle of our NSERC/CIHR effort, we were presented with an opportunity to write a proof-of-concept grant based on the proof-of-feasibility we were actively pursuing. Luckily, the team had come far enough to believe we were on the right track. We believed that large scale curie-level production of Tc-99m using existing cyclotron technology was indeed possible. The ensuing effort was—in contrast to the current way of doing things—ridiculous.

With extensive, continuous input from several top scientists from around the country, I stitched together a document 200 pages long. It was a grant that was supposed to redefine how the most important isotope in nuclear medicine was produced. 200 pages, well 199 to be exact, describing a process—THE process—we were hopefully going to be working on for the next 18 months. We waited…success! And we began.

The effort started the same way as the document – with nothing more than a blank piece of paper. Blank in the sense that we knew what we had to do, we just had not defined exactly how we were going to achieve our goal. But what happened next was a truly remarkable thing; with that blank sheet, I witnessed first-hand a team of people imagine a solution, roll up their sleeves and turn those notions into reality.

If you would like to read the PET report, click here




Paul Schaffer is the head of the Nuclear Medicine Division at TRIUMF. For the past 18 months, he and his team have been devising a method for Canada and the world to have an alternative way to produce medical isotopes. Currently, these isotopes are created on aging nuclear reactors, which are beginning to show signs of wear by needing emergency repairs. These repairs stop the flow of isotopes, affecting hundreds of thousands of people around the world. This is an inside perspective of what it means to work on the front line, and be in the media spotlight.

I’m going to start this post with the day I had the privilege of standing in front of a group of reporters along with a few of my esteemed colleagues to announce that we had, in fact, delivered on a promise we had made just over a year ago; the promise of making medical isotopes with existing hospital cyclotrons. We had set out to prove that it was possible to produce Tc-99m on a small medical cyclotron and at quantities sufficient to supply a large urban centre. The solution to Tc-99m shortages is to decentralize production. It was an example of Canadian innovation at its best – by taking a group of existing machines in existing facilities already tasked at making various other medical isotopes and extending the functionality of those facilities to produce another isotope.

Paul presenting his team's findings

The response from the press was remarkable to witness. The interest was swift, broad, and far reaching. The 24-hour news cycle had begun and with it came a deluge of requests for radio, TV, and print interviews. In the ensuing days I read a number of wonderful reports from capable reporters, often writing about a topic well outside of their background or familiarity. For that, I admire the work that they collectively pulled together in the short amount of time involved.

Something else happened, though; something I didn’t anticipate – the ensuing media blitz ended up becoming a very personal social experiment, an intense self-examination. On the way to my first-ever national television interview, I can distinctly remember reality sinking in—for most of my life, I’ve dealt with significant hearing loss. In my ever-quiet world, acutely and perpetually punctuated by tinnitus, verbal communication can be a consuming task.

It is a fact that I comprehend only 33% of the words spoken to me and that my brain fills the gaps using whatever facts it can absorb from my surroundings—expressions, moving lips, and other non-verbal cues. In that car on the way to the interview, I couldn’t help but to continuously wonder about how I would handle verbal questions on camera? What do you say on live TV when you can’t for the life of you figure out what your conversational counterpart is saying? My wingman kept reassuring me, giving background from experience and many, many reassuring comments; but deep down I had to wonder, was this the moment when the whole situation would finally come undone? My charade of being able to hear the world around me would finally end. Worse still, had the moment come to sell the team’s amazing accomplishments on national TV, with a significant number of people literally watching; and all I kept wondering was: will it fall apart simply over an unheard or misinterpreted question? Good thing most communication is non-verbal.

The interview ended up being remote, with the reporters in Ontario and a conspicuous 5 second ‘safety’ delay between what I thought I heard and what showed up on the TV monitor facing me. Five seconds was long enough for them to cut out a fleeting wardrobe malfunction, should I become a bit too passionate during my scientific descriptions, but not nearly long enough to spare a poor soul a repeat question. So, seated in a large, empty, and thankfully quiet studio it began with a single chair, bright lights, and an audio test – ‘please count to 5’ came in over the ear piece…this out of context and no non-verbal queue jolted my fear into reality. I couldn’t understand the question. Out of the corner of my eye, I could see my wingman turn a shade lighter. Worry was setting in. The in-studio producer was almost dumbstruck – this ‘expert’ couldn’t count to five.  45 seconds to ‘go’ and he repeated the question. I got it, counted to five….30 seconds….15, an ambulance was coming, getting louder, I couldn’t hear the commercial any longer…..10, the ambulance was on the street directly below. I had to look away from the TV screen, as the delay was overwhelmingly distracting. 5 seconds. The sirens were starting to recede and before you knew it, I was live.

Paul on CTV News

At first I didn’t want to watch the interview, but family, friends and colleagues from across Canada starting chiming in and eventually convinced me to watch. I felt satisfied with the results, relieved that I had heard every question, answered everything without wandering or forgetting what the question was, covering the topics I wanted to cover. However, I was definitely watching an objective projection of somebody I wasn’t familiar with. I won’t get into the details of what I saw – it’d be different for everyone, but the experience has been life altering, as has this project. That said, I’m proud of the team that has worked so well and so hard together for the past 18 months. It’s been a remarkable project on all fronts. Whether our results continue to keep their momentum and become a permanent solution to the isotope issues that plagued us for two years remains to be seen. I do know success when I see it, and this team of Canadian scientists, engineers, and medical professionals should all be immensely proud of what they have done. They are Canadian innovation at its best.

The team of TRIUMF scientists Paul collaborated with on the groundbreaking project



A Grumpy Note on Statistics

Tuesday, March 13th, 2012

Last week’s press release Fermilab about the latest Higgs search results, describing the statistical significance of the excess events, said:

Physicists claim evidence of a new particle only if the probability that the data could be due to a statistical fluctuation is less than 1 in 740, or three sigmas. A discovery is claimed only if that probability is less than 1 in 3.5 million, or five sigmas.

This actually contains a rather common error — not in how we present scientific results, but in how we explain them to the public. Here’s the issue:

Wrong: “the probability that the data could be due to a statistical fluctuation”
Right: “the probability that, were there no Higgs at all, a statistical fluctuation that could explain our data would occur”

Obviously the first sentence fragment is easier to read — sorry![1] — but, really, what’s the difference? Well, if the only goal is to give a qualitative idea of the statistical power of the measurement, it likely doesn’t matter at all. But technically it’s not the same, and in unusual cases things could be quite different. My edited (“right”) sentence fragment is only a statement about what could happen in a particular model of reality (in this case, the Standard Model without the Higgs boson). The mistaken fragment implies that we know the likelihood of different possible models actually being true, based on our measurement. But there’s no way to make such a statement based on only one measurement; we’d need to include some of our prior knowledge of which models are likely to be right.[2]

Why is that? Well, consider the difference between two measurements, one of which observed the top quark with 5 sigma significance and the other of which found that neutrinos go faster than light with 5 sigma significance. If “5 sigma significance” really meant “the probability that the data could be due to a statistical fluctuation,” then we would logically find both analyses equally believable if they were done equally carefully. But that’s not how those two measurements were received, because the real interpretation of “5 sigma” is as the likelihood that we would get a measurement like this if the conclusion were false. We were expecting the top quark, so it’s a lot more believable that the excess is associated with the top quark than with an incredibly unlikely fluctuation. But we have many reasons to believe neutrinos can’t go faster than light, so we would sooner believe that an incredibly unlikely fluctuation had happened than that the measurement was correct.[3]

Isn’t it bad that we’d let our prior beliefs bias whether we think measurements are right or not? No, not as long as we don’t let them bias the results we present. It’s perfectly fair to say, as OPERA did, that they were compelled to publish their results but thought they were likely wrong. Ultimately, the scientific community does reach conclusions about which “reality” is more correct on a particular question — but one measurement usually can’t do it alone.


[1] For what it’s worth, I actually spent a while thinking and chatting about how to make the second sentence fragment simpler, while preserving the essential difference between the two. In this quest for simplicity, I’ve left off any mention of gaussian distributions, the fact that we really give the chance of a statistical fluctuation as large or larger than our excess, the phrase “null hypothesis,” and doubtless other things as well. I can only hope I’ve hit that sweet spot where experts think I’ve oversimplified to the point of incorrectness, while non-expert readers still think it’s completely unreadable. ;)

[2] The consensus among experimental particle physicists is that it’s not wise to include prior knowledge explicitly in the statistical conclusions of our papers. Not everyone agrees; the debate is between Frequentist and Bayesian statistics, and a detailed discussion is beyond the scope of both this blog entry and my own knowledge. A wider discussion of the issues in this entry, from a Bayesian perspective, can be found in this preprint by G. D’Agostini. I certainly don’t agree with all of the preprint, but I do owe it a certain amount of thanks for help in clarifying my thinking.

[3] A systematic mistake in the result, or in the calculation of uncertainties, would be an even likelier suspect.


My Time at AAAS 2012

Thursday, March 8th, 2012

Jordan is an English major on a Communications co-op term at TRIUMF. This is his take on the AAAS conference that took place this February in Vancouver. AAAS is a conference that gathers researchers from around the world from all disciplines to share ideas with each other, the media, and the public.

It is difficult to write about any event, be it a concert or a science convention, without slipping into a pattern that resembles a mad-lib (e.g. “I saw noun and it was adjective!”). In order to avoid that particular pitfall, it’s important to focus on the individual connection one forges with the event, the broader implications of the event, and the emotions evoked by it. AAAS 2012 was, surprisingly, an event suffused with emotion. I say “surprisingly” because “science” is a word that carries with it the connotation of a stodgy atmosphere built upon cold rationalism. Despite this, the atmosphere at AAAS 2012 was built on anything but.

AAAS 2012 began on a typical (see: rainy) Friday morning in Vancouver, but the mood inside the exhibit hall was in stark contrast to the gloom outside. Though it was quite early in the morning and a number of exhibitors were frazzled and silently checking and rechecking their to-do lists, the hall quickly became characterized by laughter and discussion. People dropped by booths asking after old friends they had previously worked with, smiling at the old memories and the assurances that their friends were doing well. People who knew each other only by reputation met on the floor of the exhibit hall and traded stories about their current projects and experiments. People who did not know one another perused booths, asked questions, handed out business cards, and walked away deep in thought. The entire exhibit hall was a microcosmic example of the scientific community as a whole; a community fueled by curiosity, collaboration, camaraderie, and a friendly sense of competition. Though Friday was not open to the public, there were still a number of unique visitors, particularly American Junior Academy of Science (AJAS) members to students who had registered for student scholarships through TRIUMF and the BC Innovation Council (BCIC). These students were given a full conference pass and a one-year membership to AAAS. The AJAS members and student scholarship recipients displayed a sense of curiosity and mental alacrity befitting the next generation of scientists as they interacted with one another and the ideas presented at numerous booths.

The free public event, Family Science Days, opened on Saturday and it made the excited atmosphere of Friday seem funereal. The enthusiastic chatter of the children who attended Family Science Days with their parents in tow created the feeling only generated by like-minded individuals, radically diverse in ages and backgrounds, interacting with one another without any sense of pretension or disingenuousness. It was an interesting example of how science has the power to unify people. This is fitting, since the theme of the conference was  “Flattening the World: Building a Global Knowledge Society.” To me, the theme of the conference was fully realized when I looked around and saw the old educating the young and the young inspiring the old with a vigor for attempting to understand the unknown and a heavy reliance on the words “why” and “how.” I’m sure this brought a smile to every scientist’s face, knowing that the inquisitiveness that has spurred scientific discovery for thousands of years remains an inextinguishable human trait that will always express itself, irrespective of one’s age or background.

In describing the emotions I witnessed, I have neglected to mention the emotions I experienced during my time at AAAS 2012. Being an exhibitor, I suspect I felt more stress than many of the regular attendees. It wasn’t like being stressed about exams; it was more like unveiling a piece of art and stressing about whether people would enjoy it – more butterflies than flop sweat. As my comrades—wartime slang is perfectly appropriate in this situation, I think—and I began to entertain visitors with magnet demonstrations and educate them about cyclotrons, the worry dissipated and gave way to excitement. People were enjoying our booth and I got to test the boundaries of my memory, attempting to recount the entire Wikipedia page for “Cyclotrons” and “Higgs boson.” I’m not a scientist—far from it, in fact—but I enjoyed the lively discussions and even managed to actually learn a thing or two in the process.



Anatomy of an aurora

Thursday, January 26th, 2012

This week the Earth has seen some increased magnetic activity in the upper atmosphere, and that means we got to see aurore! Across Northern Europe and the Northern USA people looked to the skies to see the northern lights. An aurora is one of the most beautiful sights in the natural world, and a phenomenon that actually tells us a lot about the Earth and how it interacts with its environment.

Those who followed me on Twitter (@aidanatcern) may have already seen some of the wonderful images of aurorae. There are dedicated webcams that capture the night sky, and you can see some sample images at the Aurora Webcam archive.

Aurora over Alaska (wikimedia)

Aurora over Alaska (wikimedia)

When charged particles accelerate or decelerate, or recombine in pairs, they emit electromagnetic radiation, and it is this radiation that we see in the aurora. The color of the light depends on the wavelength of the radiation, and the intensity of the light depends on how much radiation is emitted. That means that there is always an aurora above us, but if the energy of the radiation is too low, or the intensity is too weak, we won’t see anything. Once we know how to interpret the light we can learn something about the radiation that is emitted. Usually we see a variety of colors in an aurora and each color corresponds to a different wavelength, so if we can see a region of the sky that is all one color, we know that the wavelength (and hence the energy, ignoring the effects of aberration) must be the same. That means we can “map” the sky and find contours of wavelength.

Since the particles are accelerating, there must be something that causes the acceleration. The Earth’s core is made of (among other materials) molten iron. The rotation of the Earth means that this core is also rotating, and a rotating fluid magnetic medium creates a magnetic dipole, giving the Earth magnetic North and South poles. These poles are aligned near the geographic North and South poles of the Earth, but not exactly. (In fact, magnetic North and South keep moving and from time to time they even swap places. The exact mechanism behind this is not yet fully understood, but geological records show it happens every few hundred thousand years. Simulations suggest that the rotating magnetic fluid is a chaotic system, so the reversals occur at stochastic, or random, intervals of time.)

The sun produces a stream of particles, known as the solar wind, and they create their own electromagnetic field. The two fields, from the Earth and the sun, interact and they force charged particles in the upper atmosphere along curved paths. As the particles move along these paths they accelerate, decelerate and recombine, and that is what produces the aurorae. The most recent increase in magnetic activity can be traced back to a huge coronal mass ejection that arrived from the sun. This video shows the arrival of the flare:

The effect looks impressive, but don’t be scared, solar winds like this are perfectly harmless. Far bigger winds have hit the Earth in the past few billions years and life has continued to flourish in spite of them. Life has adapted to the Earth’s magnetic field and this field protects us from the high energy particles.

It turns out that while looking up at the night sky is a beautiful and moving experience in itself, it is also important to particle physicists. Some of the most important discoveries in the last century came from a different phenomena, cosmic rays. Cosmic rays are very high energy particles (usually protons) that travel huge interstellar distances and rain down on the Earth in much the same way that the solar wind does. They interact with the upper atmosphere to create cascades of particles, and usually the muons are the only detectable particles that reach sea level. Interactions of these cosmic rays gave rise to the discovery of the muon (“Who ordered that?!”), the pion and the kaon, the lightest forms of mesonic matter. It was around this time that large scale accelerators were developed, and we found hundreds of new mesons and baryons. Cosmic rays gave us a very small glimpse into a rich “zoo” of particles that has occupied physicists ever since.

Eventually, when we have exhausted our ability to accelerate particles to higher energies we might need to rely on cosmic rays again. There are proposals to develop ground based detectors to study the interactions of extremely high energy particles from outer space. Those particles have the potential to reach energy regimes we can only dream of at the moment. (Incidentally, this is one of the ways that we know for sure that the LHC cannot destroy the world. The universe creates much more energetic particles than we could ever hope to create in our accelerators, and since the universe seems to be in one piece we can conclude that the LHC is safe on Earth!)

An aurora from above (Expedition 28 on board the International Space Station)

An aurora from above (Expedition 28 on board the International Space Station)

If you’re fortunate enough to see an aurora then take a few moments to think about the huge forces at work, the vast distances involved, and how the colors tell us so much about how the Earth and solar wind behave. It really is one of the most beautiful phenomena in the universe.


Change of state

Friday, November 25th, 2011

A few weeks ago I bumped into one my group’s former students, Rozmin. She’s still jetlagged from her journey here and she had the look on her face that told me she’d been through the change of state. She’d transitioned from a grad student to a postdoc. The metamorphosis is not an easy one, and in fact no matter how much time you spend preparing for it, and how long it takes, there are always some surprises.

A while back she was still editing her thesis. Today she is finding her feet in a new role, one with more responsibilities, more challenges and fewer safety nets. From now on, students will look to her for help, and expect to get answers. I should point out that grad students do a great deal of the work here at ATLAS, and they answer a lot of the questions we have, and perform a lot of the studies that we need. But they’re here primarily to learn, the postdocs are primarily here to work, and at the back of our minds we have prejudices about our roles. As a postdoc I feel that I should be mentoring students and helping them, rather than having them help me, even though I spent most of my first year here playing catch up with students who knew the experiment inside out. As a student on BaBar, what mattered most was getting the thesis written, and I felt that it was okay to make mistakes, ask for help and tell people I didn’t really know what I was doing.

Becoming a postdoc

Becoming a postdoc

The difference between being a student and a postdoc is mostly cosmetic, and a lot of the time it’s hard to tell whether someone has graduated yet. The real difference is one of attitude. When Rozmin was a student she was impressed that I seemed to know a little bit about every part of particle physics, especially the history. She would ask me how I knew about the history of CP violation and the tau-theta puzzle, and I’d reply knowingly “It’s a postdoc thing.” “Like a special power?” “Yeah, postdoc power!” Of course at that point she knew it was a bit of an act. I knew little more than she did, but I said it with confidence, and that inspires confidence in others. I’ve had quite a few roles where I had to put on an act of confidence like that. One of my favorite examples was when I worked for a telephone helpline where there was a locked desk drawer full of secret help for the coordinators. When I finally saw what was inside I was surprised to find nothing but a bottle of gin, some chocolate, and an electric drill. I asked what the drill was for and they replied “To stop volunteers messing around with it.” Huh. It looks like sometimes we need to be told that the only source of reassurance is feigned confidence.

Sometimes this is all the help you get...

Sometimes this is all the help you get...

There’s no magic solution, no ancient wisdom and in research, everything is new. Once you realize that, and once you realize that everyone is out of their depth and everyone is working without a safety net, life becomes much easier. Then you can tell your grad students what they need to hear. “That’s an interesting question, let’s look it up online” means “I don’t know any more than you do”, “Let’s talk to Frank about this over coffee” means “I have no idea how to even get started on this problem, but I could use a break”, and “A similar study was tried at UA1″ means “I have a tiny amount of information about this from a long time ago, but at least that means it’s not completely new.” And so on. It’s takes a while to get used to. I even managed to get a taste of life as a Professor recently. When faced with a particularly challenging problem the head of our department told me simply “Welcome to the world of supervision!” In that world, the stakes are higher, the help is rarer and it takes even more courage to make decisions with so much uncertainty.

Naturally there are more changes than a slightly different day job. Rozmin has had to move house (to a different continent) again and settle down somewhere new. This is one of the most traumatizing experiences a person can go through, so doing it in French, when your husband is thousands of miles away and you’ve got a high pressure job (as well as your student’s high pressure job) taking up all your time, it can get even more tricky. The dynamic of our friendship has changed since she got back, as we spend more time together, going for a coffee or a drink, talking about our respective jobs and problems. The shift in our friendship has brought us closer and now we’re both free of our theses, and can focus on what we came here for, the physics.

It's all about the small achievements

It's all about the small achievements

It’s challenging, it’s scary, it’s all about the unknown and even the unknowable. But it’s like I always say: We don’t these things because they’re easy, we do them because they’re hard.

Happy Thanksgiving Weekend! Thanks to Jorg Cham for the comics. PHD Comics


In the shadow of Shiva

Thursday, November 10th, 2011

In front of one of CERN’s most imposing and industrious buildings stands a statue of Dancing Shiva. During the day it’s a beautiful reminder of the friendship between CERN and India, celebrating the cosmic ballet that surrounds us all. By night it casts an ominous shadow over building 40, where discoveries are made, decisions are taken, results are shared and gossip is spread. But what does Shiva represent to us?

Working in the shadow of Shiva

Working in the shadow of Shiva

The Dancing Shiva represents the changes in the universe around us, as matter and energy constantly bump into each other, create and destroy systems and keep renewing the world. I suppose we can attach any meaning we like to this, the constant chatter of culture, the renewal of our population as people die and children and born, the violent cosmological events that keep reorganizing the universe. Any and all of these interpretations are beautiful, powerful and majestic, but for me there is one interpretation which excites me more than any other and holds a very deep truth in it. This cosmic dance is the interaction of matter and antimatter.

Whenever we create new particles we create them in matter-antimatter pairs. They are literally equal and opposite components that make up everything we see. When they meet, they destroy each other in a burst of energy. If that was all there was to matter and antimatter, it would make a rather beautiful cosmic ballet, but not an interesting one. The fascinating part of the story is when we remember that we have more matter than antimatter, which means that this particular cosmic ballet is unbalanced, and the statue is a constant reminder of this fact.

The universe knows something we don't.  And it acts on cosmic scales.

The universe knows something we don't. And it acts on cosmic scales.

We don’t know why nature prefers to matter to antimatter, and until we know why we can’t really claim to understand how the universe works. We know how one mechanism has a preference (the weak force interacting with quarks) but this is much too small to explain the whole story. Whenever collide protons together at the LHC we have to live with the fact that we’re colliding matter with more matter in a detector made of matter. The particles that escape are not quite half matter half antimatter, as we might like. After a while, all the particles (except the neutrinos) slow down, decay and hit some rock. They join the rest of the stuff around them and either annihilate or get comfortable and settle in with their surroundings. All we’re really doing is moving matter around in a very complicated way; nature balances the books and every piece of antimatter we created (except the antineutrinos) gets removed from this small part of the universe. The cosmic dance continues, and if we’re lucky we get a small glimpse into how it really works. On the tiny, insignificant scales we work on we don’t see much of an imbalance at all. When we look up to the stars we see matter everywhere we look, across vast distances and far back in time.

Nature’s balance sheet has a few implications for our physics. For example, every time we produce a Higgs boson, we also produce a lot of noise in the detectors as well. In a matter-antimatter collider (such as LEP or Tevatron) this is less of a problem, since the Higgs boson is neither matter nor antimatter, it’s equal amounts of both. To create a Higgs boson we would need to create at least one antiparticle, and that takes a lot of energy. With this extra particle we get a lot more particles “for free”, leading to all kinds of noise!

So in the light of day, when CERN is teeming with life Shiva seems playful, reminding us that the universe is constantly shaking things up, remaking itself and is never static. But by night, when we have more time to contemplate the deeper questions Shiva literally casts a long shadow over our work, a bit like the shadows on Plato’s cave. Shiva reminds me that we still don’t know the answer to one of the biggest questions presented by the universe, and that every time we collide the beams we must take the cosmic balance sheet into account.

It’s rare that we get a symbol that inspires both clarity and beauty. It’s almost poetic. Why does Shiva prefer to destroy antimatter more than matter? The more data we gather the better chance we have of finding the answer to that question. I don’t think we’ll ever stop wondering about this question. It’s the reason there’s something instead of something and antisomething. It’s the reason atoms exist and stars can form. And yet the answer is still out of our grasp.


To start, let me say that there are extremely strong reasons to believe that the OPERA experiment’s measurement of neutrinos travelling faster than light is flawed. We knew that from the moment it came out, because it contradicts General Relativity (GR), which is an extraordinarily well-tested theory. Not only that, but the most obvious ways to modify GR to allow the result to be true give you immediate problems that contradict other measurements. To my knowledge, there’s no complete theoretical framework that makes predictions consistent with existing tests of GR and allows the OPERA result to be right.

But in my view of how experimental physics is done, history has shown us that once in a great while, something is discovered that nobody thought of and nobody can fit into the existing theoretical mold. The measurements that led to the discovery of GR in the first place provide a good example of this. Such shifts are extremely rare, but I don’t like the idea of ignoring a result because it doesn’t fit with the theories we have.

No, we have to address the measurement itself, and satisfy ourselves that there really was a mistake. There are many ideas for what might have gone wrong, and as far as I know, the discussion is ongoing. I’m not an expert on it, but I know enough to disagree with some of the blogosphere discussion lately that has pronounced that the case is closed. There seem to be two categories of claims going around:

  1. Articles that point out that the OPERA result is inconsistent with other measurements, as in this piece by Tommaso Dorigo (who is, incidentally, my colleague now that I’ve joined CMS). These are of course correct within the context of GR or any straightforward modifications thereof, as I said right at the start of this post. The question is whether there’s some modification that can accomodate the results consistently, and that’s a very hard thing to exclude. (There is some good discussion in the comments of Tommaso’s post about this, in fact.)
  2. Articles that the OPERA result has been refuted because someone posted an idea on the arXiv server. A current example is this preprint, which asserts that a 60 nanosecond delay might be explained by OPERA having made a relatively trivial mistake in their GPS calculations. Of course, it’s possible that a trivial mistake has been made. But I’m not inclined to consider it definitive, especially because the author has already partially backpedaled upon learning more about how GPS works.

It’s great that people are sending ideas for what might have gone wrong with the result, or how it might be explained. But let’s wait for the discussion to settle down — and, indeed, for OPERA to finalize their paper — before we conclude that the case is closed. I do expect the result to be disproven, but what I want to see is one of these things:

  1. OPERA finds that there really was a problem with their measurement, revises it, and the “superluminal” effect goes away.
  2. Another experiment makes the same measurement, and gets a result consistent with GR.

Either way, I’ll consider the case closed, but there’s no reason to get ahead of ourselves. Doing science usually doesn’t mean knowing the answer in time for tomorrow’s news.


– By Byron Jennings, Theorist and Project Coordinator

Pierre-Simon, marquis de Laplace (1749 – 1827) was one of the great French mathematical physicists. In math, his fame is shown by the number of mathematical objects named after him: Laplace’s equation, Laplace transforms, the Laplacian, etc.  In physics, he was the first to show that planetary orbits are stable and he developed a model—the nebular model—to account for how the solar system formed.  In modified form, the nebular model is still accepted. In spite of these important contributions, he was also very much a lackey, being very careful to keep on the right side of all the right people. During the French revolution, that might have been just good survival strategy. After all, he served successive French governments and, unlike Lavoisier, kept his head.

Laplace presented his definitive work on the properties of the solar system to Napoleon.  Napoleon, liking to embarrass people, asked Laplace if it was true that there was no mention of the solar system’s Creator (ie God) in his opus magus. Laplace, on this occasion at least, was not obsequious and replied, “I had no need of that hypothesis.” This is essentially the simplicity argument discussed in a previous blog, but stated very crisply and succinctly.

Laplace was not just a whistlin’ Dixie. Newton had needed that hypothesis, ie God, to make the solar system work. Newton believed that the planetary orbits were unstable and unless God intervened periodically, the planets would wander off into space. Newton had not done the mathematical analysis sufficiently completely. Laplace rectified the problem. Newton also had no model for the origin of the solar system. Laplace eliminated these two gaps that Newton had God fill.

Back to Napoleon—he told Joseph Lagrange (1736 – 1813), another of the great French mathematicians/physicists, Laplace’s comment about no need for the God hypothesis. Lagrange’s reply was, “Ah, it is a fine hypothesis; it explains many things.” Laplace’s apocryphal reply was, “This hypothesis, Sir, explains in fact everything, but does not permit to predict anything. As a scholar, I must provide you with works permitting predictions.” This is the ultimate insult in science: it explains everything but predicts nothing. Explanations are a dime a dozen; if you want explanations, read Kipling’s Just so Stories. Now, there are some fine explanations. I particularly like The Cat That Walked by Himself.

Lapalce’s argument, I had no need of that hypothesis, is still being used today. Hawking and Mlodinow in their book, The Grand Design, created a stir by claiming God did not exist. But their argument was just Laplace’s pushed back from the beginning of the solar system to the beginning of universe:  they had no need of that hypothesis.  Whether their physics is correct or not is still an open question. It is not clear that string theory has gotten past the “it explains everything but predicts nothing” stage.

An alternate approach to understanding God’s absence in scientific models is methodological naturalism. The term seems to have been coined by the philosopher Paul de Vries, then at Wheaton College, who introduced it at a conference in 1983 and published it in the Christian Scholar’s Review.  It has since then become a standard definition of science, even playing a significant role in court cases, most notably the case [1 in Dover Pennsylvania on teaching creationism in public schools. The judge mentioned methodological naturalism prominently in his ruling.

Methodological naturalism, as a definition of the scientific method, is rather ill defined except for its main idea, namely that science, explicitly, by fiat, and with malice a-fore-thought, rejects God, gods, and the supernatural from all its considerations. There is frequently an implicit secondary idea that science is about finding explanations but only natural ones, of course. Both ideas are inconsistent with what science actually is: building models constrained only by observation and parsimony. (See above and the previous blog for my opinion of the role of explanations in science.)

However, methodological naturalism is a very convenient hypothesis. It avoids awkward questions about the relation between science and religion. By inserting naturalism into the very definition of science, methodological naturalism, if valid, would create a firewall between science and religion. This would both protect religion from science and scientists from the religious. Considering the violence done in the name of religion, the latter may be more important, but the former was probably part of the original intent.  However, I suspect the main motivation was to explain why God and the supernatural are absent from science.  But Laplace gave the real reason for God’s absence: parsimony—there is no need of that hypothesis. There are probably also very good theological reasons for that absence but that is outside the scope of science and this blog.

Methodological naturalism confuses the input with the output. To the extent science is naturalistic, it is an output of the scientific method, not part of the definition. Excluding anything by fiat is poor methodology. But once one realizes that historically God and the supernatural have been eliminated from science, not by fiat, but by Laplace’s criteria, methodological naturalism becomes redundant; an ad hoc solution to an already solved problem.


[1] United States District Court for the Middle District Of Pennsylvania, TAMMY KITZMILLER, et al. v. Dover Area School District; et al,