|Source: Quanta Magazine|
On March 17, a panel of four astrophysicists held a press conference at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., to announce that they had discovered features in the cosmic microwave background (CMB) that are consistent with gravitational waves from the universe’s first moments. The results agreed with predictions from the decades-old theory of inflation, said panelist Chao-Lin Kuo of Stanford University, providing the first direct evidence that for an infinitesimal instant after the Big Bang, our universe expanded faster than the speed of light.
Kuo had designed the sensitive photon detectors in the telescope responsible for the breakthrough. For three years in the cold, dry atmosphere of the South Pole, the Background Imaging of Cosmic Extragalactic Polarization (BICEP2) telescope collected photons from the CMB, the 13.8-billion-year-old residue of the Big Bang. Information describing the intensity and polarization of the captured photons was transmitted by satellite to an international collaboration of 47 researchers working at various institutes. Gradually, a pattern of polarized light emerged. The researchers were initially reluctant to interpret the data as evidence for primordial gravitational waves. They labored to rule out alternative explanations for the signal, including the possibility that the pattern had been generated not by gravitational waves but by dust in the Milky Way.
In mid-March, a panel of four astrophysicists working on an experiment to probe the first moments of time held an extraordinary press conference at the Harvard-Smithsonian Center for Astrophysics (CfA) in Cambridge, Mass. The scientists announced that a radio telescope located at the South Pole had discovered gravitational waves generated by the Big Bang. They posted a non-peer-reviewed paper on the Internet that proclaimed the beginning of a “new era” in cosmology.
Sharing the spotlight at the press conference were Andrei Linde and Alan Guth, two theoretical physicists who have developed seminal theories of how our universe rapidly inflated at its birth. The new results validated those theories — or so it seemed.
Stanford University and the CfA both distributed press releases calling the discovery a “smoking gun” showing that the theory of inflation is true, a phrase that appeared in international headlines about the findings. A short video of Stanford researcher Chao-Lin Kuo walking up Linde’s driveway to share the news of the discovery was viewed by millions. Smiling physicists and cosmologists nearly danced with excitement in media interviews.
Early-Universe Explorer Looks for Answers, (pro)
A Bold Critic of the Big Bang’s ‘Smoking Gun’, (con)
both by Peter Bryne