Discovery Files

Catching the Fever

Particle Fever discovers the human element to physics

March 14 is just a bit heady if you happen to like math or science. It's Einstein's birthday. It's Pi Day, and this year in Washington, D.C., it's just a week before the local premiere of Particle Fever.

This documentary film features the world's most powerful particle collider and follows seven scientists and engineers for five years. It focuses on the period from when they switched on the Large Hadron Collider to when they ultimately discovered the Higgs boson and presented those findings at CERN, the European Organization for Nuclear Research.

So today we honor Albert Einstein, who won the Nobel Prize in Physics in 1921, who interpreted Planck's quantum hypothesis realistically to explain the photoelectric effect in 1905, and who helped spawn debating, theorizing and testing that influenced the field of quantum physics. This advanced science and paved the way for the discovery detailed in Particle Fever.

By the end of March, Particle Fever will have opened in most major markets, and while the story delineates scientific processes, many too will take away messages about the excitement of discovery, the immense challenge to proving or disproving physics theory and the very human side of physics.

The National Science Foundation (NSF) partially funded Particle Fever producer and physicist David Kaplan of Johns Hopkins University as he began making this movie. Particle Fever director Mark Levinson has been noted as being a physicist-turned-director, but few realize the inverse of that equation in Kaplan, who started college as a film student before discovering his clear love for physics.

'Could be nothing or everything...'

Kaplan has said he had to ignore how irrational it was to think about making a documentary about science when he had no idea of how it ended. However, his hunch was that whatever the outcome, the impacts would be historic. His attitude was to plunge ahead and believe that at some point he'd have a compelling story. But between the significant personal financial and emotional investment, mechanical setbacks at CERN and the uncertainty of the experiment itself, pressure was inevitable.

His approach was to find scientists to follow with camera crews periodically and provide video cameras to others for "selfies," hoping for the good fortune of targeting people who would create the inevitable excitement of being involved in such a significant event in the field of physics.

Kaplan has said it wasn't so much about verifying and discovering the Higgs boson, it felt more like a story about the scientific journey to discovery. And ultimately, Particle Fever provides us with highs, lows, uncertainty and professional exhilaration. We laugh. We cry. And most of all, we move through the movie with all the compelling characters, sharing in their trepidation and thrill in this scientific adventure. Kaplan hoped this would convey an enthralling story.

Turns out he was right.

NSF: Why do you need such a big contraption as the five-story-tall Large Hadron Collider to see something as small as a boson?

DK: Quantum mechanics says that particles and waves are two aspects of the same thing. The fundamental particles, like the electron, somehow behave like a wave. The electron interferes; it doesn't just scatter. It interferes with other particles. It interferes with itself. It's weird. To see something very tiny, you need tiny waves. And a tiny wavelength is a high frequency, which is high energy, and so to see tiny, tiny, tiny things, you need a very high energy beam. So the Large Hadron Collider is that large, so you can accelerate protons to a high enough energy to create the waves--the proton waves--so tiny that you can start to see tiny things.

NSF: What is your favorite scene in Particle Fever?

DK: My favorite scene is with Savas (Dimopoulos) and an older physicist, Riccardo Barbieri who in a sort of, not-typical way was really ready to retire. [NOTE: In this scene, the two men discuss the challenge for theoretical physicists who often don't get to see their theories proven within their lifetime and how it can leave a feeling of wondering whether they made a difference.] Working very hard, Barbieri chose a time when he was going to retire and really not do physics any more. And physicists--including Riccardo--don't speak emotionally or personally about their experience being a physicist and hopes and disappointments. We don't think like that. We're sort of active all the time. You're supposed to fail most all the time, so it's okay. I didn't know [that scene] was going to be that poignant, but it summarized the unspoken feeling of all of us. That's my favorite scene for many, many reasons.

NSF: What were the worst and best parts of making Particle Fever?

DK: The worst part of making Particle Fever was the emotional and intellectual commitment that it required and took away from my family...and physics. And the best part was the support of the community. It was scary to go and do something that was not physics because the social capital in physics is "what are you working on?" It doesn't have to be a big breakthrough; it just has to be contribution to what we're all trying to figure out. And so, "You're going off and making a movie?" How are people going to respond to that? Almost universal approval and support for the project was very fulfilling. That, and "OK, David, when are you going to come back?" reminding me that there's a home to come back to when this is all done.

NSF: How have people responded to the movie?

DK: Non-physicists and scientists alike have responded positively. I think scientists respond positively because they think, "Yeah, that's how it is. Nobody ever shows how it really is." Science documentaries, which are to teach science, are not about the experience. [I found that] what's important is the experience of the physics for the physicist. And so all the graphics we put into the movie--the goal was that they look like what is in the head of the physicist and not perfectly all laid out gorgeous so you really see what this dimension looks like. That wasn't the goal. How do physicists think? And it's in very simple lines and very simple representations. So I think the scientists enjoyed that "yes, this is my world-people understand me." And the non-scientists felt something even if they didn't understand the physics: "Wow I can feel something about this, not just, "oh, that's cool." I think that's why it works.

NSF: What work will you do next as a physics researcher?

DK: There are a variety of things that I think are is dark matter, which I have done work on. One is black hole information, which I've done no work on, but I'd love to learn about it. It's hot right now. I'm usually very late to these games, but maybe I find something that people miss. But whatever it is [I pursue], it's going to be something I find truly interesting. This is my rule: Always do something you think is really cool, not because you think someone else will like it or because you think it will get you a job. Because whatever you think is cool and you work hard at it, you'll get good at that. And eventually people will ask you to do more of that. And that's what you want to have happen.

Some additional physics facts

One of the most interesting aspects to Particle Fever is that it starts a discussion about the science behind the Higgs boson. Physicist Greg Mack addresses two of these issues. He is also a NSF Science & Technology Policy Fellow sponsored by the American Association for the Advancement of Science.

How do protons create a Higgs boson?

In the Large Hadron Collider (LHC), protons, which are the positive particles in an atom's nucleus, smash together to create new particles. We can again thank Einstein for the idea behind how this is possible: energy and mass are intimately related. His famous equation E = mc2 says that mass m and energy E are two forms of the same thing and can be converted into each other, related by the speed of light c. This also says that it takes a lot of energy to make a little matter, since the speed of light is such a large number.

As Particle Fever documents, the experiments at the LHC found that the Higgs boson has 125 times more mass than a proton. How can two small protons colliding together make something bigger? One has to boost the protons, giving them a lot more energy to add into the mix. This goes along with David Kaplan's explanation of why the LHC has to be so big--the bigger the contraption, the more energy that can be added! The very strong magnets and huge circular structure of the LHC can accelerate the protons to extremely high speeds, giving each one an energy of about 7,000 times the mass of an ordinary proton.

When two protons collide at such high speeds and energies, they don't just bounce off each other. Protons actually are made up of particles called quarks, which are held together by gluons. In these collisions, it's the quarks and gluons that hit. This is where the extra energy is key--the whole process takes the quarks, gluons and energy, smashes them all together and spits out new particles. When that happens, some of that energy can be converted into mass, making particles such as the Higgs that are bigger than the original particles. The colliding proton beams make a bunch of new particles--bigger and smaller--and it is up to scientists to interpret what the detectors record.

What's a 'Gee-ee-Vee?'

In Particle Fever, the high energy physicists Kaplan, Dimopoulos and Barbieri don't talk about mass in kilograms. To them, it makes more sense to talk about mass in terms of energy. They are interchangeable after all, as Einstein said. It all hinges on what's most useful for discussion and calculations.

Instead, mass is talked about in units of the electronVolt: the energy an electron gains or loses when it's exposed to one volt of electricity. That unit is abbreviated as "eV" and pronounced as "ee-Vee." This is actually a small number for the measurement of mass, and in Particle Fever the scientists talk about "Gee-ee-Vee" or "GeV": a gigaelectronVolt. Adding the prefix "giga-" to the unit multiplies it by a billion, so this translates as a billion electronVolts.

Why is this useful? A proton has a mass of about 1.7 x 10-27 kilograms. That's a very small and messy number. In electronVolts, the proton has a mass of about 1 GeV. Yes, 1 GeV-a number much more easily managed. It's then easy to compare how big other particles are, such as when the LHC made the Higgs discovery at a mass of 125 GeV.

Watch the trailer and find out more about Particle Fever.