I think this is an interesting (but rather lengthy) commentary on the personal side of the research leading to the most recent Physics Nobel Prize. I am curious to know what others think, especially those who feel that there are scientific conspiracies to squash the truth about climate change or evolution. I can't imagine any of these people with their all too-human emotions pretending to do research on something they know is false.
Science 6 April 2012:
Vol. 336 no. 6077 pp. 26-31
DOI: 10.1126/science.336.6077.26
A Week in Stockholm
Yudhijit Bhattacharjee
For the rival teams whose discovery of dark energy had transformed scientists' picture of the universe, the 2011 Nobel festivities were a flurry of jubilation, disappointment, and one-upmanship.
Early morning on 4 October 2011, the day the physics Nobel was announced, astrophysicist Peter Garnavich was woken up by a phone call that came not from Stockholm but from his wife, Lara Arielle Phillips. Garnavich was asleep in a Chicago hotel room, preparing for a long day of travel. Arielle was calling from the couple's home in Indiana, where both are professors at the University of Notre Dame. “Is everything all right?” Garnavich asked groggily. “Yes, everything's fine,” Arielle said, mildly apologetic. “The Nobel in physics has been awarded for the accelerating universe. It's going to Brian, Adam, and Saul.”
Garnavich had known all along that this day would come. In the 13 years since two rival teams discovered the accelerating expansion of the universe—suggesting that three-quarters of the cosmos consists of a mysterious force termed dark energy—the consensus that the work would win a Nobel Prize had come to be matched by a growing certainty about who the individual winners might be. The Shaw Prize, awarded in 2006, had already singled them out: Brian Schmidt and Adam Riess from the High-z Supernova Search Team—which Garnavich was a part of—and Saul Perlmutter, leader of the competing Supernova Cosmology Project (SCP). Yet, when his wife named the winners, all he could say was, “$#!!.” The disappointment of being left out was far more intense than Garnavich had imagined.
“I had thought this was really going to happen a long time from now, and I didn't have to deal with it, but now I did have to deal with it,” says Garnavich, a genial 53-year-old with a perpetual smile. At the same time, he felt relieved that the Nobel committee had not given the prize to Perlmutter alone. “The jockeying for which team was first in making the discovery had gone on for a long time, and there was a worry that maybe the Nobel committee wouldn't have seen that.”
Garnavich wasn't the only one feeling this mix of pride and pain. Nicholas Suntzeff, a goateed, balding astronomer at Texas A&M University in College Station, who co-founded the High-z team in 1994 along with Brian Schmidt, took a deep breath when he heard the news on National Public Radio that morning. “I was disappointed, and I was disappointed that I was disappointed,” he would recall later. In Cambridge, Massachusetts, Harvard University astrophysicist Robert Kirshner—who had been the doctoral adviser to both Schmidt and Riess—comforted his daughter when she asked angrily, “Daddy, why didn't you win?” Explaining the rules of the Nobel, which prevent awarding the prize to more than three individuals, did not help mollify her. “She didn't care about any of that stuff, she wanted her father to win,” Kirshner says. Later, when colleagues e-mailed to offer congratulations tinged with condolence, Kirshner responded with the mellow sarcasm that he's known to direct at others and himself alike. “It's not every day that you don't win a Nobel Prize,” he wrote.
The winners knew what the others were feeling. At 7:56 a.m. EDT, Riess dug out from an avalanche of requests for media interviews to e-mail his gratitude to the High-z team. “Dear colleagues,” wrote Riess, a professor at Johns Hopkins University in Baltimore, Maryland, “We accept this in your names. It's all of ours to share. We are lucky ducks to get to work on this adventure.” Schmidt, a professor at the Australian National University in Canberra, followed with a message that read in part: “While the prize has been awarded to Adam and myself, we all know it is in recognition of the whole team's work.” Perlmutter, a physicist at Lawrence Berkeley National Laboratory (LBNL) in California and a professor at the University of California, Berkeley, conveyed similar sentiments to the members of the SCP. Later that day, a comment in the media from British astronomer Martin Rees acted as a salve for those who had been left out. “It would have been fairer, and would send a less distorted message about how this kind of science is actually done, if the award had been made collectively to all members of the two groups,” Rees told Reuters.
Within hours of the announcement, Schmidt and Riess decided to invite the remaining 17 members of the High-z team to Stockholm for the Nobel ceremony. Each laureate would be allowed 14 tickets to the various events organized by the Swedish Academy, and between the two of them, Schmidt and Riess had enough tickets to accommodate everybody and their spouses. The spare tickets they gave to Perlmutter, who had a bigger challenge with the 30 collaborators that he wanted to invite. By December, all arrangements had been made to bring both teams to the world's grandest scientific celebration, with the three laureates spending roughly $100,000 from the $1.5 million prize to pay for their guests' airfares, hotel rooms, tuxedo rentals, and other expenses. After years of a deep and sometimes hostile rivalry, the two groups would have a chance to revel in their shared glory, sip champagne side by side, and possibly reconcile their warring narratives of the discovery in a scientific colloquium at the end of the celebrations.
Monday, 5 December Arrival
December is bleak in Stockholm. On most days, the sun sets at 2:00 p.m., enveloping the city in a darkness that seems merciful at the end of what has usually been a gray, overcast morning. The joke among guests attending the Nobel festivities is that the Swedes invented the Nobel Prize to bring cheer to Stockholm in its darkest month and boost the local economy with an influx of tourists.
The two teams began arriving in the city on 5 December. All of the High-z members had rooms reserved at the magnificent Grand Hotel, where laureates stay. The Grand was already full by the time the SCP team made reservations, so its members had to find rooms elsewhere. “We were a bit late off the gate,” says Andrew Fruchter, a member of Perlmutter's group.
In the race that led up to the discovery of the accelerating universe, however, Perlmutter's group had been the first to start. Founded in the early 1980s by Carl Pennypacker and Richard Muller, both physicists at LBNL, the SCP began as an effort to find nearby supernovae using an automated search technique. The technique involved taking telescopic images of the same swaths of sky at different times and using an algorithm to contrast those images to spot supernovae that might have exploded in the time between two shots. In 1988, the group proposed applying the technique to find distant supernovae. As outsiders to astronomy, Pennypacker and Muller faced a constant challenge in getting funded. For this, they would later blame a prominent member of the yet-to-be-formed High-z team: Kirshner, who by virtue of his supernova expertise was on proposal review committees appointed by the Department of Energy and the National Science Foundation.
By 1991, Pennypacker's interests had turned to science education, and Muller had shifted to studying weather patterns. The two handed the reins of the SCP to Perlmutter—a hawk-nosed, tenacious, young physicist who had been Muller's graduate student. Perlmutter's impressive organizational skills helped seal his position as the undisputed leader of the project, even though the group included a senior, and at the time, more distinguished, physicist named Gerson Goldhaber.
Perlmutter systematized the search technique. He demonstrated that one could more or less guarantee finding supernovae by taking a reference image of a patch of the sky just after a new moon and subtracting it from another image of the same sky taken right before the next new moon. Through the early 1990s, Perlmutter expanded the group by recruiting collaborators in Europe and Australia. What had begun as a team of physicists grew to include several astronomers. But the group still had a tough time persuading review committees of telescope facilities to grant them observing time.
While the SCP was led by physicists interested in astronomy as a tool to understand the universe, the High-z collaboration grew out of a team of astronomers who realized that Type 1a supernova explosions could help them answer a fundamental physics question: the fate of the cosmos. These astronomers—including Mario Hamuy, Nicholas Suntzeff, Mark Phillips, and others—had been studying nearby Type 1a supernovae for years before they began the search for distant Type 1a supernovae. Because the universe is expanding, far-off supernovae recede from Earth at such great velocities that their light reaches us stretched in wavelengths toward the red end of the electromagnetic spectrum—a “redshift” represented by the letter z. That's why these objects are known as high-redshift or high-z supernovae. Unlike Perlmutter's group, the High-z team was a flat organization. Even though Schmidt was technically the leader, the team was a collaboration among equals, with different members getting primary authorship on papers that they individually led about different aspects of the work.
In 1993, the year before the team began taking those high-redshift observations from the Cerro Tololo Inter-American Observatory in Chile, the observatory's Mark Phillips made a discovery that would prove to be fundamental to using Type 1a supernovae for cosmological measurements. Although in theory these supernovae were supposed to have uniform luminosity, astronomers had learned that Type 1a supernovae could in fact differ somewhat in brightness. Phillips found that the time a Type 1a supernova took to fade away was related to its peak brightness: The faster it faded, the fainter it was at the height of its luminosity. This so-called Phillips relationship enabled both teams to calibrate Type 1a supernovae based on the number of days it took for the explosion to grow dim, allowing astronomers in essence to determine the precise wattage of a distant cosmic light bulb.
By 1996, the two teams were locked in a dead heat to find as many distant Type 1a supernovae as possible and determine their distance and velocity in order to measure what everybody expected to be a deceleration of the universe's expansion. Each group considered itself the front-runner: Perlmutter's because it had started earlier, and the High-z collaboration because it understood Type 1a supernovae much better. In 1998, after the teams submitted their final results for publication, much of the astronomical community declared the race a tie. A new contest began: a prolonged battle for credit through rival campaigns to narrate the history of the discovery. Kirshner wrote a popular book, The Extravagant Universe, chronicling the details from the High-z team's perspective. LBNL put out its own narrative of the discovery through press releases, weighted in favor of the SCP, and Perlmutter wrote reviews crediting his team with having led the way.
Wednesday, 7 December Reception
As Nobel Week began, with a reception hosted by the Royal Swedish Academy of Sciences, any tensions were drowned in sparkling wine. It was dark and rainy outside the academy's 96-year-old building as members of the two teams filed in through its pillared entrance, joining hundreds of guests inside. Some went to hang their overcoats in a large cloakroom where a giant portrait of the 16th century astronomer Tycho Brahe hangs on the wall, evoking an era when science was a far more individualistic enterprise.
Wandering through the crowd, Fruchter of the SCP met members of his group whom he had never seen in person. He bumped into researchers from the High-z team and exchanged pleasantries. The High-z team's Suntzeff, still jet-lagged, had a small golden pin on his lapel that resembled the pin that all the laureates were wearing. “I had quite a few students coming up to me, and then realizing, ‘Uh-oh, this guy is not a Nobel laureate,’” Suntzeff says. After a while, he took the pin off and put it in his pocket.
Thursday, 8 December Nobel Lectures
When Kirshner stepped out of the Grand Hotel the next morning, it was surprisingly sunny and bright. Like the other members of the High-z team, he was going to board a bus to Stockholm University for the Nobel lectures. But while Kirshner was waiting, a shiny, black BMW drove up to take Riess to the lecture hall. Riess climbed into the back seat of the limo, which the Nobel Foundation provides to every laureate, along with a personal attendant and a chauffeur. Riess offered his former adviser a ride to the venue, and Kirshner got in the passenger seat.
The limo sped through the city streets. For a few moments, the two men rode in silence: Riess in the back, a frizzy-haired 40-year-old with a reddish-blond goatee, youthful enough to pass as a grad student, with a down-to-earth manner unburdened by gravitas; Kirshner in the front, the smooth-talking, flamboyant Harvard don who had taught Riess and Schmidt all the supernova astrophysics they needed to do their work. In an alternate universe, Kirshner could have been riding in the back seat; to have two students get the Nobel was at once both more and less than winning it himself.
After a while, Kirshner reached over to turn down the seat warmer. The driver glared. “She gave me the look that meant, ‘You don't do that, I do that,” Kirshner says. “So I said, ‘Well, I have a Ph.D. from Caltech.’” The driver was unmoved. “We don't even let the laureates do that,” she replied. “I thought, ‘Okay, I've been put in my place,’” Kirshner says.
At the lecture hall, Kirshner went off to take his seat in the audience while Riess joined Schmidt and Perlmutter to get ready for the talks. Weeks before the event, the three winners had conducted a long negotiation among themselves by teleconference to decide who would speak first. Perlmutter wanted to go first, but Riess and Schmidt did not agree: The two of them were still smarting from having gotten insufficient time to speak at the Shaw Prize ceremony 5 years before, where Perlmutter spoke first. “He covered a lot of ground there,” Riess says. “He went soup to nuts.” In the end, they struck a deal: Perlmutter would deliver the Nobel banquet speech on behalf of all three, whereas Schmidt and Riess—in that order—would precede him at the Nobel lecture.
Thursday, 8 December Lunch
After the lectures, the two teams went their separate ways to attend celebratory lunches: one hosted by Perlmutter on an island 45 minutes from Stockholm, the other hosted by Schmidt and Riess at a restaurant in the Royal Art Academy building on the city's waterfront. As the High-z team gathered at their venue, Schmidt looked over the restaurant's wine selection to order for the group. He was the right man for the job. An affable, chubby-cheeked 44-year-old who grew up in Montana and Alaska, Schmidt owns a winery in Canberra whose last few cases of Pinot Noir sold out within hours of the Nobel announcement in October.
A Riesling wine arrived, and toasts were raised. Riess, with a gleam in his eye, kept telling the others, “We have a really nice gift for you.” Kirshner was amused. “Adam, he's funny. He can't keep a secret,” Kirshner says. “Adam needs a lot of attention and a lot of response. He was like that as a graduate student. He's still like that.”
Without Riess's youthful impatience, however, the High-z team might never have been here. Although Schmidt was the leader of the High-z team, it was Riess's marathon data analysis in the fall of 1997 that helped the team catch up to Perlmutter's group and ultimately cross the finish line a little bit sooner. Riess had already made a key contribution with his dissertation on how to cancel out the dimming effect of dust clouds obscuring a supernova, thereby getting a more precise measurement of its brightness. It was this work that enabled the High-z team to perform the calculations necessary for the breakthrough, despite having a smaller clutch of Type 1a supernovae to go on than their rivals did. When Riess's analysis showed that the universe was accelerating—not decelerating as everyone had expected—he didn't back down in the face of skepticism from his colleagues and worked with urgency to write what became the discovery paper.
But Riess was also lucky. Garnavich, who was then a postdoc at Harvard University, had already completed the analysis of a subset of those Type 1a supernovae, which provided a hint of the final result. Garnavich's analysis had shown that the universe would continue to expand forever, rather than slow down and recollapse in what theorists had previously predicted to be a big crunch. The finding, which Garnavich announced at a meeting of the American Astronomical Society in January 1998, alongside a similar announcement by Perlmutter's group, made the front page of The New York Times. “But it was a limited number of supernovas,” Garnavich says. “It turned out we needed smaller error bars to see that the universe was not just going to expand forever, but that it was also accelerating.” In Stockholm, celebrating Schmidt and Riess's honor with the rest of the team, Garnavich was reminded once again that his paper had been a few supernovae short of the Nobel.
The main courses came and went: salt-poached perch, beef wagyu, and other fancy dishes, each paired with its own wine. In the middle of it all, the conversation was interrupted by a loud banging on the window. A pedestrian walking by the restaurant had glimpsed flames erupting behind a curtain, unbeknownst to everybody inside. A set of T-shirts that one of the team members, Peter Challis, had brought along for his colleagues, each printed with the slogan “Dark energy is the new black,” had caught fire. Challis had put them behind a curtain, too close to a candle. It fell to Harvard astronomer Christopher Stubbs to douse the flames with his drink.
After the dishes were cleared away, Riess and Schmidt unveiled the surprise gift: cuff links engraved with “q0 < 0”—the inequality representing the discovery. (q0 is the cosmological deceleration parameter, which the High-z team's calculations determined to be negative, indicating that the universe was undergoing the opposite of deceleration.) Riess had ordered them from a Baltimore gift store, after showing store attendants the equation in the discovery paper. “I said, ‘It really has to be the same italic font. It has to be the subscript zero that's lower and smaller, it's not Q Zero,’” he says. “I knew my colleagues have very sharp eyes.”
Meanwhile, Perlmutter and his colleagues were partaking of a Swedish Christmas smorgasbord with 16 kinds of smoked fish and other delicacies on the Fjäderholmarna, a luxurious group of islands on Stockholm's east coast. Muller gave a toast extolling Perlmutter for a richly deserved honor. It was a view that everybody in the group shared—including Pennypacker, who had come up with the original idea for the project. “I don't know if I would have been capable of steering the project like Saul did,” Pennypacker says. “The founders are not the ones who take it to the next level of success.”
But Perlmutter's group, too, had its share of controversy over credit. One member who felt slighted was Gerson Goldhaber, who had hoped to win the Nobel along with Perlmutter. In the years before he died in 2010, Goldhaber gave several talks in which he described himself as the first in his group to discern what the data were showing.
“He came home late one night in September 1997 and said, ‘Guess what? There won't be any big crunch,’” says his widow, Judith Goldhaber, who joined Perlmutter's group for the celebrations in Stockholm. “He was not happy that others didn't jump up and say, ‘Hooray, hooray,’ and announce it.” Perlmutter, ever cautious, wanted to check and double-check everything, a process that took a long time. “Gerson thought if the group had put more people on that job in a more aggressive way, they would have clearly beaten the other team,” Judith says. An optimist, Goldhaber believed he had a good chance of winning the prize as “a third man,” along with the leaders of the two teams. “So in a way, it was good that he died before the Nobel was announced,” Judith says.
Saturday, 10 December Nobel Ceremony
On Saturday, the day of the ceremony, the laureates were chauffeured to the Stockholm Concert Hall, where they took their seats on an enormous stage decorated with yellow and white flowers. Members of the two teams arrived by bus; some would later joke about feeling a sense of accomplishment merely at having successfully donned a Swedish tuxedo. Everyone rose as the king and queen of Sweden took their chairs on stage, marking the beginning of one of the world's most elegant annual ceremonies.
For the physics prize, Perlmutter's name was called first. He walked up to the king to accept the gold medal and the diploma that all laureates get. As he shook the king's hand, trumpets blared in the background, somewhat sooner than he'd expected from rehearsals earlier in the week. Momentarily rattled, Perlmutter stepped back and froze for a few seconds instead of bowing to the king right away. Watching from their seats, Schmidt and Riess worried that Perlmutter had forgotten to bow.
“Adam and I are sitting next to each other going, ‘Bow, bow,’ under our breaths,” Schmidt says. “Finally, Saul came to his senses and bowed.” As Perlmutter walked back, Schmidt and Riess greeted him with a relieved smile. “I'm so glad you went first,” Schmidt whispered.
The Nobel banquet followed, an extravagant affair with an army of waiters serving more than 1300 guests. On the tables were bowls filled with chocolate discs wrapped in golden foil, embossed to look like the Nobel. “Coming back from the Nobel ceremonies,” Suntzeff wrote in a Facebook update after the banquet. “As I expected, it was bittersweet, as was the Nobel Gold medal chocolate dollar I got.” He later added: “Chocolate doesn't fix things, but it really helps!”
Monday, 12 December Colloquium
On the afternoon of 12 December, members of the two teams gathered at the Albanova University Center in Stockholm for a colloquium on the discovery. The event had been organized by Swedish scientists led by Ariel Goobar, a physicist at Stockholm University and a member of Perlmutter's group. “The idea was to get both sides of the story, and in good harmony,” Goobar says. “It was quite an experiment.”
After a week of lecturing and media interviews, the Nobelists were grateful to be able to moderate instead of having to give a speech. One by one, the other members came up to deliver brief talks.
Kirshner, who had a plane to catch, was among the early speakers. His first slide showed a picture of astronomer Charles Kowal, who had died just a few weeks earlier. In a 1968 paper that would prove to be prescient, Kowal wrote that distant supernovae would one day be used as standard candles to measure the deceleration of the universe. In another slide, Kirshner paid tribute to Fritz Zwicky, who had found several supernovae beginning in the 1930s by searching during the darkest phase of the moon. The implied point, one that Kirshner had made at length in his book and elsewhere, was that—at least in Kirshner's view—Perlmutter had not pioneered the search for supernovae in the way that his group claimed.
“Since the length from one dark of the moon to the next is about 29 days, and the rise time of a Type 1a supernova [the time the explosion takes to reach peak brightness] is 21 days, this makes the search in each dark of the moon very effective for finding supernovae,” Kirshner told Science. “[Perlmutter's group] seems to believe they invented this. That may be true in some sense, but they didn't invent it first. Zwicky did, and that's how we were doing the observing at the Palomar Observatory when I was responsible for a month of the supernova search in 1971.” Because Perlmutter and his core team of collaborators weren't astronomers, Kirshner says, “they were not very conscious that some of the problems they needed to solve had already been solved by others.”
Kirshner ended his talk magnanimously, noting that “it was the hard work of the people in this room that made [the discovery] happen sooner rather than later.” Then, Kirshner turned to Perlmutter and handed him a copy of his book that he had inscribed with a note: “Everybody deserves a lot of credit.” Perlmutter accepted it, smiling.
It wasn't long before Kirshner received a return jab from the SCP's Richard Ellis, an astronomer at the California Institute of Technology in Pasadena. Ellis showed a comment that Kirshner had written as a referee of a 1989 Nature paper by Ellis and a group of Danish astronomers, reporting the discovery of the first distant Type 1a supernova. Although Kirshner had endorsed the paper, he had also been skeptical of the authors' enthusiasm for expanding the search to ultimately measure the cosmic expansion rate. Because Kirshner had waived his confidentiality as a referee, Ellis had no qualms putting up the report as a slide. He read out the relevant portion in a mocking tone. “[The authors] are embarked on a difficult path which we all hope will succeed,” Kirshner had written, “but we should all think carefully before deciding how much time should be spent with HST [Hubble Space Telescope] or on the ground in this exceptionally difficult work.” The audience laughed, and Kirshner smiled through it all sportingly.
Midway through the colloquium, a warmer reminiscence from the SCP's Peter Nugent, an LBNL astronomer, dispelled whatever tensions were hanging in the air. It was a story from March 1997, when both teams were taking turns looking for distant Type 1a supernovae using the 4-meter Blanco telescope at the Cerro Tololo observatory. After a long night of observing, Nugent was driving down the mountain in one of the observatory's old Volkswagen Beetles when the brakes failed. Schmidt, walking to the laundry room near the observatory's dormitory, saw the Beetle hurtling down the mountain road. As Nugent—eyes bloodshot from a sleepless night—rounded the last bend, the car headed straight toward Schmidt.
Nugent steered the car onto a ridge right in front of the dorm, forcing it to roll over on its side. He emerged dazed but unhurt. Later, Schmidt told Nugent his first thought as he jumped out of the way was, “First they bring their damn computers that are going to beat us to the punch, and now he tries to kill me.” Nugent was pleased to learn that Schmidt had been the first person to pull him out of the car.
At the end of the talks, Matt Mountain, director of the Space Telescope Science Institute in Baltimore, asked if the two teams would work with each other to probe dark energy, the mysterious force that appears to be causing the universe to accelerate.
Perlmutter answered that they would, noting that he had collaborated with Riess on at least one occasion in the years since the discovery. The teams got together outside the auditorium for their first combined group photo, although Kirshner and a few others were not there. Within the next couple of days, nearly all of the researchers had returned home.
Epilogue
Perlmutter forgot Kirshner's book at the auditorium that afternoon. “It did get shipped to me later,” he says. Perlmutter says he disagrees with several of Kirshner's interpretations of events but is tired of debating them. “Anytime there's any discussion on this, you get a nine-page letter from Bob,” Perlmutter says. “You could spend your life arguing with Bob, or you could go off and do other things.”
In the end, the competition between the teams benefited science, Schmidt says. “We both had to work more quickly and better and smarter,” he says. And everybody agrees that having two teams arrive at the same result strengthened the world's confidence in the discovery. That's what led to the Nobel's being awarded a mere 13 years after the discovery, rather than the typical 30 to 40 years.
Riess says it was inevitable that many co-discoverers would feel left out, and he acknowledges that including them in the Nobel ceremonies is likely to have offered only partial consolation. “This is just the way it went down,” he says. “There was a lot of precursor work required for this discovery. There is precursor work to the precursor work. Science is a never-ending chain of progress. We all stand on the shoulders of what came before.”
On 14 December, the day after Suntzeff returned to Texas A&M, he got an e-mail informing him that his parking spot had been moved to a location he calls the “worst parking spot” on campus. Suntzeff thought ruefully about Perlmutter at UC Berkeley, where the university grants Nobel laureates free parking for life. But he says he also realized how trivial the indignity was in the face of the discovery that he had helped to make. Two days after the Nobel announcement, he had written to the High-z team: “I hope that our friendship will withstand the Nobel, and the contradictory feelings of elation, jealousy, pride in accomplishment and the sting of lack of recognition outside our community.” He ended the note by reminding everybody that “no one else in history save our two groups, will ever be able to say, ‘we discovered most of the Universe in 1998.’”