“You may speculate from the day that days were created,
but you may not speculate on what was before that.”
—Talmud, Tractate Hagigah 11b, 450 A.D.
To go back to the beginning, if there was a beginning, means testing the dominant theory of cosmogenesis, the model known as inflation. Inflation, first proposed in the early 1980s, was a bandage applied to treat the seemingly grave wounds cosmologists had found in the Big Bang model as originally conceived. To call inflation bold is an understatement; it implied that our universe began by expanding at the incomprehensible speed of light ... or even faster! Luckily, the bandage of inflation was only needed for an astonishingly minuscule fraction of a second. In that most microscopic ash of time, the very die of the cosmos was cast. All that was and ever would be, on a cosmic scale at least—vast assemblies of galaxies, and the geometry of the space between them—was forged.
For more than 30 years, inflation remained frustratingly unproven. Some said it couldn’t be proven. But everyone agreed on one thing: If cosmologists could detect a unique pattern in the cosmos’s earliest light, light known as the cosmic microwave background (CMB), a ticket to Stockholm was inevitable.
Suddenly, in March 2014, humanity’s vision of the cosmos was shaken. The team of which I had been a founding member had answered the eternal question in the affirmative: Time did have a single beginning. We had proof. It was an amazing time indeed.
For weeks I had known it was coming. Our entire team was furiously working to finalize the results we would soon make public. We had relentlessly reviewed the data, diligently debating the strength of the findings, discussing what could be one of the greatest scientific discoveries in history. In the intensely competitive world of modern cosmology, the stakes couldn’t have been higher. If we were right, our detection would lift the veil on the birth of the universe. Careers would skyrocket, and we would be forever immortalized in the scientific canon. Detecting inflation equaled Nobel gold, plain and simple.
But what if we were wrong? It would be a disaster, not only for us as individual scientists but for science itself. Funding for our work would evaporate, tenure tracks would be derailed, professional reputations ruined. Once gleaming Nobel gold would be tarnished. Glory would be replaced by disappointment, embarrassment, perhaps even humiliation.
The juggernaut rolled on. The team’s leaders, confident in the quality of our results, held a press conference at Harvard University on March 17, 2014, and announced that our experiment, BICEP2, had detected the first direct evidence of inflation—evidence, albeit indirect, of the very birth pangs of the universe. (...)
For years BICEP2 looked for a swirling, twisting pattern (called a B-mode polarization pattern) in the CMB that cosmologists believed could only have been caused by gravitational waves squeezing and stretching space-time as they rippled through the infant universe. What could have caused these waves? Inflation and inflation alone. BICEP2’s detection of this pattern would be evidence of primordial gravitational waves generated during inflation, all but proving that inflation happened.
Then we saw it. There was no going back.
The broadcast from Harvard’s Center for Astrophysics captivated media around the world. Nearly 10 million people watched the press conference online that day. Every major news outlet, from The New York Times to the Economist to obscure gazettes deep within the Indian subcontinent, covered the announcement “above the fold.” My kids’ teachers had heard about it. My mother’s mahjong partners were kvelling about it.
Watching the live video, I could see MIT cosmologist Max Tegmark reporting the event. He wrote, “I’m writing this from the Harvard press conference announcing what I consider to be one of the most important scientific discoveries of all time. Within the hour, it will be all over the web, and before long, it will lead to at least one Nobel Prize.”
Finally, we’d seen what we, and the whole world apparently, had wanted to see. The BICEP2 team’s announcement was that we had read the very prologue of the universe—which, after all, is the only story that doesn’t begin in medias res.
Still, doubts plagued me. It sure seemed to be a discovery for the ages. But was it? No one is immune from confirmation bias. And scientists, despite what you may think, are rarely mere gatherers of facts, dispassionately following data wherever it may lead. Scientists are human, often all too human. When desire and data are in collision, evidence sometimes loses out to emotion. It was impossible to rule out every possible contaminant. Had we fretted enough?
The most worrisome aspect of BICEP2’s signal was how huge it was. It was shockingly big, more like finding a crowbar in a haystack than a needle, as one team member phrased it. At the time of our announcement, we were worried about being beaten by our chief competitor, a $1 billion space telescope called the Planck satellite with the perfect heavenly perch from which to scoop us. Prior to BICEP2’s press conference, Planck had already ruled out a B-mode signal half as big as the one we claimed to have observed. Cosmologists were expecting a whisper. We claimed BICEP2 had heard a roar. (...)
A few days later, I got wind of a colloquium that Princeton University’s David Spergel had given just after the Harvard press conference. David said he had spotted a blunder in our results, that our data were contaminated by dust within the Milky Way galaxy. Soon, I found out there were others at Princeton laser-focused on the way we modeled dust. The BICEP2 leadership had anticipated an onslaught, perhaps even a backlash, from the Princeton folks, who were working on several competing B-mode experiments. Maybe they were just frustrated after being scooped on another major CMB discovery.
I asked Matias if it was David Spergel alone causing his concerns. Ominously, Matias said, “I think there is nothing else people here talk about.” My heart stopped. Princeton’s cosmology program is the top-ranked in the country—cosmology’s own Holy See, comprised of the world’s best experimentalists and theorists, among them multiple members of the National Academies of Sciences. It felt like an inflationary Inquisition, one that could put the BICEP2 results on a modern-day Index of banned pre-prints.
Imagine finding out the entire IRS is obsessed with your tax return. Not just one rogue auditor, but everyone, from the Secretary of the Treasury on down, fixated on your Form 1040! It was petrifying.
but you may not speculate on what was before that.”
—Talmud, Tractate Hagigah 11b, 450 A.D.
For more than 30 years, inflation remained frustratingly unproven. Some said it couldn’t be proven. But everyone agreed on one thing: If cosmologists could detect a unique pattern in the cosmos’s earliest light, light known as the cosmic microwave background (CMB), a ticket to Stockholm was inevitable.
Suddenly, in March 2014, humanity’s vision of the cosmos was shaken. The team of which I had been a founding member had answered the eternal question in the affirmative: Time did have a single beginning. We had proof. It was an amazing time indeed.For weeks I had known it was coming. Our entire team was furiously working to finalize the results we would soon make public. We had relentlessly reviewed the data, diligently debating the strength of the findings, discussing what could be one of the greatest scientific discoveries in history. In the intensely competitive world of modern cosmology, the stakes couldn’t have been higher. If we were right, our detection would lift the veil on the birth of the universe. Careers would skyrocket, and we would be forever immortalized in the scientific canon. Detecting inflation equaled Nobel gold, plain and simple.
But what if we were wrong? It would be a disaster, not only for us as individual scientists but for science itself. Funding for our work would evaporate, tenure tracks would be derailed, professional reputations ruined. Once gleaming Nobel gold would be tarnished. Glory would be replaced by disappointment, embarrassment, perhaps even humiliation.
The juggernaut rolled on. The team’s leaders, confident in the quality of our results, held a press conference at Harvard University on March 17, 2014, and announced that our experiment, BICEP2, had detected the first direct evidence of inflation—evidence, albeit indirect, of the very birth pangs of the universe. (...)
For years BICEP2 looked for a swirling, twisting pattern (called a B-mode polarization pattern) in the CMB that cosmologists believed could only have been caused by gravitational waves squeezing and stretching space-time as they rippled through the infant universe. What could have caused these waves? Inflation and inflation alone. BICEP2’s detection of this pattern would be evidence of primordial gravitational waves generated during inflation, all but proving that inflation happened.
Then we saw it. There was no going back.
The broadcast from Harvard’s Center for Astrophysics captivated media around the world. Nearly 10 million people watched the press conference online that day. Every major news outlet, from The New York Times to the Economist to obscure gazettes deep within the Indian subcontinent, covered the announcement “above the fold.” My kids’ teachers had heard about it. My mother’s mahjong partners were kvelling about it.
Watching the live video, I could see MIT cosmologist Max Tegmark reporting the event. He wrote, “I’m writing this from the Harvard press conference announcing what I consider to be one of the most important scientific discoveries of all time. Within the hour, it will be all over the web, and before long, it will lead to at least one Nobel Prize.”
Finally, we’d seen what we, and the whole world apparently, had wanted to see. The BICEP2 team’s announcement was that we had read the very prologue of the universe—which, after all, is the only story that doesn’t begin in medias res.
Still, doubts plagued me. It sure seemed to be a discovery for the ages. But was it? No one is immune from confirmation bias. And scientists, despite what you may think, are rarely mere gatherers of facts, dispassionately following data wherever it may lead. Scientists are human, often all too human. When desire and data are in collision, evidence sometimes loses out to emotion. It was impossible to rule out every possible contaminant. Had we fretted enough?
The most worrisome aspect of BICEP2’s signal was how huge it was. It was shockingly big, more like finding a crowbar in a haystack than a needle, as one team member phrased it. At the time of our announcement, we were worried about being beaten by our chief competitor, a $1 billion space telescope called the Planck satellite with the perfect heavenly perch from which to scoop us. Prior to BICEP2’s press conference, Planck had already ruled out a B-mode signal half as big as the one we claimed to have observed. Cosmologists were expecting a whisper. We claimed BICEP2 had heard a roar. (...)
***
Within three weeks of the press conference, 250 scientific papers had been written about our results. That was astonishing; a paper is considered “famous” if it has 250 citations over the course of decades! Then, in early April, I got an email from the physicist Matias Zaldarriaga. How many times can he be congratulating me, I wondered?“When the dust is low, but spread over a wide area, it betokens the approach of infantry.” —Sun Tzu, The Art of WarMatias’s April email was no “attaboy.” He was disturbed. He wanted to talk details. What did I know and when did I know it? It was the beginning of a trial I had long feared. Rumors were swirling at Princeton about the way we had used the infamous Planck slide. “People here in Princeton are very concerned about dust,” he said, ominously adding, “In fact they have managed to convince me that there is not a very good reason for me to believe it is not just dust. Have you looked into the foregrounds yourself?” Of course I had looked at the foregrounds—potential sources of contamination such as polarized emission from the Milky Way’s dust. The whole team had been worried about our galaxy producing spurious B-mode polarization that would masquerade as primordial gravitational wave B-modes. But data at low frequencies from BICEP1 and at high frequencies from Planck’s scrubbed PowerPoint slide convinced us we were okay.
A few days later, I got wind of a colloquium that Princeton University’s David Spergel had given just after the Harvard press conference. David said he had spotted a blunder in our results, that our data were contaminated by dust within the Milky Way galaxy. Soon, I found out there were others at Princeton laser-focused on the way we modeled dust. The BICEP2 leadership had anticipated an onslaught, perhaps even a backlash, from the Princeton folks, who were working on several competing B-mode experiments. Maybe they were just frustrated after being scooped on another major CMB discovery.
I asked Matias if it was David Spergel alone causing his concerns. Ominously, Matias said, “I think there is nothing else people here talk about.” My heart stopped. Princeton’s cosmology program is the top-ranked in the country—cosmology’s own Holy See, comprised of the world’s best experimentalists and theorists, among them multiple members of the National Academies of Sciences. It felt like an inflationary Inquisition, one that could put the BICEP2 results on a modern-day Index of banned pre-prints.
Imagine finding out the entire IRS is obsessed with your tax return. Not just one rogue auditor, but everyone, from the Secretary of the Treasury on down, fixated on your Form 1040! It was petrifying.
by Brian Keating, Nautilus | Read more:
Image: Amble / Wikipedia
[ed. How science works.]
