Ruminations

Blog dedicated primarily to randomly selected news items; comments reflecting personal perceptions

Friday, December 28, 2012

Higgs boson discovery may signal the world’s last physics experiment as scientists struggle to come up with next big question

Joseph Brean | Dec 28, 2012 9:11 PM ET  National Post
J.P. Moczulski for National Post
J.P. Moczulski for National Post Melissa Franklin, who chairs Harvard’s physics department despite not finishing high school, says it could be difficult to convince governments to fund searches for new forms of energy
 
What modern physics knows about the matter in the universe (better at the end of 2012 than the beginning) is that it is basically shrapnel, strange bits that endure from an ancient explosive nativity, known as the Big Bang.

What Melissa Franklin knows about modern physics (likewise better than ever, or pretty much anyone) is that it is finished. Done. Kaput.

This, says the Canadian rebel experimentalist who never finished high school and now chairs Harvard’s physics department, is the “nightmare” result of the discovery, announced this summer in Switzerland, of the Higgs boson, the God Particle.

As a key creator of ATLAS, the massive device that, with Canadian input, made the successful detection (beating the Compact Muon Solenoid, which she calls the “Romney” detector), Prof. Franklin knows the studied uncertainty with which particle physicists approach their work. They are skeptical by instinct, and deliberately open to surprises. Until she discovered the particle known as the top quark, for example, with others at Fermilab in Chicago in 1995, she could only guess what it looked like, or what it weighed.

But because the long-predicted discovery of the Higgs completes the Standard Model of particle physics by explaining why stuff has mass, it is unclear where the next big experiment should even look, or how, or for what.

Courtesy of Grimthorpe Film
Courtesy of Grimthorpe FilmCERN, Switzerland
 
Dark Matter? No one knows how to directly observe it, or if that is even possible. Dark Energy? Even weirder, a theorist’s leap of faith. String theory, the multiverse, supersymmetry: all very cool ideas that offer no falsifiable hypotheses, the basic currency of science.

And so the Large Hadron Collider, the great underground particle accelerator that straddles the French border near Geneva, and slams beams of protons into each other under the constant gaze of the two detectors, is starting to look like the world’s last physics experiment.

“If we don’t find anything other than this Higgs, and this Higgs is the Standard Model Higgs, and there’s nothing else in the data that we see, I don’t think anybody’s going to pay for us to build another accelerator,” Prof. Franklin said in an interview in Stephen Hawking’s office at the Perimeter Institute for Theoretical Physics in Waterloo, Ont. (He was not there.) “But we could. There’s lots of plans.”

Those include even bigger, interconnected circular tunnels under the Swiss mountains to gear up the proton beams even closer to the speed of light — a neat idea, but a hard sell in today’s Eurozone. Even with unlimited funds, she said, it would still be unclear what the next big experiment ought to be, and given that it takes a decade to build a collider, the hands-on expertise of a generation of experimentalists hangs in the balance.

Martial Trezzini / Keystone / The Associated Press Files
Martial Trezzini / Keystone / The Associated Press Files A view of the LHC (large hadron collider) 
in its tunnel at CERN (European particle physics laboratory) is photographed, near Geneva, Switzerland. 
 
“I think it would become clear, but I don’t think it’s clear now. I think that’s one of the problems. You can’t make a convincing argument right now about what kind of accelerator to make to study this kind of stuff. People thought that if you knew exactly where the Higgs was, you’d make an electron-positron collider just at that mass and then you’d just study it like crazy. But I’m not sure that there’s enough support for doing that if that’s the last thing we’re ever going to see, I mean, if that’s the end, the Standard Model is complete, there’s nothing else. So the thought of going ahead with doing that, but they were waiting to see where the Higgs was. Now, I don’t know whether that’s going to happen. It’s scary, actually.”

In particle physics, anything that is not forbidden is compulsory. If particles can interact in a certain way, eventually they will. The question is not when, but how often. So if a collider is powerful enough, its detectors are sensitive enough, and the theory is sound, then sooner or later physicists will find what they are looking for. In the case of the Higgs, they were looking at beams of protons moving so fast around the LHC’s 27km loop that they had decomposed into their constituent particles, quarks and gluons. With two beams in opposite directions, steered by magnets to collide inside the detectors, the Higgs finally emerged from collisions of gluons at a mass of 125 gigaelectronvolts, though only for a fleeting instant before decaying into a tangle of other more common particles.

Anything that can happen will happen, so over time, as the LHC creates more and more Higgs bosons, the various ways they are observed to decay should precisely match the theoretical predictions of how the Higgs can decay. The probabilities should add up to one. If not, something else is going on. Perhaps there is another Higgs, waiting to be detected at a higher energy. Or perhaps it can (and therefore does) decay into undetectable Dark Matter. At the moment this is idle speculation, and the LHC is likely to run for another decade in pursuit of greater certainty on these questions. After that, there be monsters.

“If all we ever found new at the LHC was the Higgs, I’d still like to go to the next energy, but I’m not sure that we could convince anybody to do it, convince governments, because we’re not saying we’re looking for something in particular. We just want to look,” said Prof. Franklin.

Particle physics evokes this same basic curiosity. It is a realm in which things are at once particle and wave, here and there, potential and real. It has shattered our understanding of ordinary stuff, and shown it to be more ephemeral, magical, and interconnected than we knew. It summons entities, like the Higgs, that have not otherwise existed since the beginning of time. It is not just a new science, but a new ontology.

It tells us that the Big Bang was not a perfectly uniform explosion. Had it been, all that would be left over is light. Instead, slight ripples in the fabric of that explosion, plus an as yet unexplained surplus of matter over antimatter, meant that the growing universe was full of particles with mass that could be shaped by the gravity of Dark Matter first into a fibrous web of simple elements, then into stars that burned and exploded, and in their vast cauldrons created the heavier elements, the stardust of which everything we know is made.

Melissa Franklin, 56, came to particle physics at a good time for an experimentalist. The years ahead would see the discovery of the W and Z bosons, before she herself co-discovered the top quark. After that, all that remained in sight was the Higgs.

It was a less auspicious time to be a woman, or as she then was, a 15-year-old girl, who convinced her parents to let her go off to school in London.

Denis Balibouse / The Associated Press Files
Denis Balibouse / The Associated Press Files     Former CERN director general Christopher Llewelyn-Smith,
 standing left, attends the presentation of results during a scientific seminar to deliver an update on the 
search for the Higgs boson at the European Organization for Nuclear Research (CERN) in Meyrin near Geneva, 
Switzerland.
 
At Christmastime in the early 1970s, in the headmaster’s office of a French lycée near the Natural History Museum, the teenage Melissa Franklin decided to learn physics after enduring a lecture about the need for a goal in her life.

“At my age, which was 15, you had to be in school. I couldn’t just live there, but I wanted to go and live somewhere.”

She describes her parents (her mother Elsa was Pierre Berton’s television producer, and her father Stephen was a journalist with Weekend magazine) as “playful.”

High school at Jarvis Collegiate had not gone well, not the school part at least, though she was educating herself, and recalls James Joyce’s Finnegans Wake as a formative reading experience she shared with bohemian friends.

“I wasn’t really learning anything, I couldn’t concentrate,” she said. “I think in today’s terms you would just call me ADD.”

Anja Niedringhaus / The Associated Press  Files
Anja Niedringhaus / The Associated Press Files 
 A wall painting by artist Josef Kristofoletti is seen at the Atlas experiment site at the European Center 
for Nuclear Research, CERN, outside Geneva, Switzerland. The painting shows how a Higgs boson may look.
 
“Also, at that point, most of the people I knew were more interested in taking drugs and drinking five dollar sherry and hanging out in Itchycoo Park [a ravine behind the Rosedale subway station, so nicknamed for the psychedelic pop song by Small Faces, with its line: “What did you do there? I got high!”]

“I have an authority problem,” she said. “I like it when people question authority.”

Thus, when the headmaster proposed a two-year course of study, perhaps in philosophy or literature because that is what her teachers thought she liked, the student was brash.
“To piss him off, I said ‘Physics.’ ”

Back in Toronto, still lacking a high school diploma, she decided to continue with physics at the University of Toronto.

CERN / AFP / GettyImages
CERN / AFP / GettyImagesA representation of traces of a proton-proton collision measured in the 
Compact Muon Solenoid (CMS) experience in the search for the Higgs boson. 
 
“I didn’t actually do the high school math, which made it really, really hard in college. Really hard. Hard my whole life. I’m not very smart. I’m not. I’m not really. But now I’m learning it [with her teenage son], and I realize now as I’m learning it through him, I realize how easy my life could have been.”

The university was reluctant to admit her, and not for the last time, to its lasting embarrassment.
“I begged. I begged for like 32 days in a row. To everyone, physics department, Innis College, anybody,” she said. “Eventually they just got sick of it.”

In response to protest that surely you cannot badger your way into UofT physics, she said, “You can. You can. Well, you could then. I just kept saying, ‘Look, I know what I want to do and most of the people here don’t.’ And I just lied about stuff, said I was brilliant. See, what SEED [an alternative summer school she attended] taught you was how to just convince people…. I loved being a student there [at UofT].”

AP Photo/Keystone/Martial Trezzini, File - In this March 22, 2007 file picture, the magnet core of the 
world's largest superconducting solenoid magnet (CMS, Compact Muon Solenoid), one of the 
experiments preparing to take data at European Organization for Nuclear Research (CERN)'s Large 
Hadron Collider (LHC) particle accelerator is seen, near Genva, Switzerland.
 
Years later, as a top researcher from California in need of a faculty position and keen to move home, she found herself in “an abusive relationship” with the UofT, variously courted and rejected by the school’s grandees — “snubbed,” as the late, great Mr. Berton once put it in a newspaper column.
“One professor, she heard, threatened to quit if she was selected. Others feared she’d organize a feminist movement on the campus — as if that were a taboo,” he wrote.

“It was pretty horrible,” Prof. Franklin said. “A person isn’t just a woman, and they have a personality. I think the University of Toronto had a lot of people who probably didn’t like my personality either. But the kind of things they said made me think they were kind of worried about having a woman who was also… a slightly more wild woman.”

Instead she went to Harvard, and became the first woman ever tenured there in physics, now department head.

“This is how physics works. [She clears her throat.] I have an idea. I tell you. You say ‘It’s wrong,’ and then it’s your job to show that it’s wrong. You say it’s wrong before you’ve even thought about it,” she said.

Intelligence aside, this brazen confidence can be a hard pose for a young woman among older men.

J.P. Moczulski for National Post
J.P. Moczulski for National Post   Melissa Franklin, chair of physics at Harvard , poses at the Stephen 
Hawking Centre at the Perimeter Institute for Theoretical Physics in Waterloo.
 
“I always wanted to develop a patch [she slaps her arm] that women could just put on, like at the beginning of college, just put it on and then you’re just confident. You could take it off in the summer, if you want,” she said. “But here’s the thing. Now we have women who are confident, but they’re confident enough to say, ‘I’m really good at this,’ or ‘I really like it, but I don’t want to be with these people for the rest of my life.’ ”

Theorists study, as Prof. Franklin puts it, “exact symmetries of an approximate world.”

Experimentalists “measure the world through a fog.” She thinks women in physics skew, like herself, toward experimentalism over theory. Each needs the other, of course, but they rarely see eye to eye. There has traditionally been an arrogance in the theorist’s outlook, epitomized for physicists by the “truffle pig” analogy, in which the theorist is a truffle farmer who knows approximately where to find his quarry, and only needs the pig to make the final detection.

That the Higgs was found more or less where it was expected has bolstered this view, and even now, Prof. Franklin has heard talk among theorists that the Geneva experiment did not discover the Higgs, but rather just checked to make sure it was there.

“I really love building things. I would hate to be a theorist,” Prof. Franklin said. “I don’t want them to show me where to snuffle.”

It is a cute line, but the truth is she does. She needs theorists to have ideas she can smack down, or prove. But she will have retired by the time the next big experiment is built, so now it is her students whose careers are on the line. What they need is a big question, and instead they have a big problem. No question.

“In the end what you need is to have your hands on things, fiddling and figuring stuff out,” she said.

National Post
• Email: jbrean@nationalpost.com

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