The most important physics discovery of 2014 later became the most highly-hyped measurement error in physics of 2014.
Of course, this is referring to the results collected by a highly sensitive telescope based in Antarctica, called BICEP2 that researchers claimed were the first detection of a cosmic phenomenon called gravitational waves. If the discovery had held true, it would have been a new way to study the farthest reaches of space and would have also added to the surmounting evidence supporting Einstein's theory of relativity. But it wasn't meant to be. To understand what went wrong, here's a little background first:
Whenever any object in space accelerates, it creates ripples in the universal fabric of space time, just like ripples in a pond. These ripples, called gravitational waves, propagate through space and are usually extremely small — far too small to detect on Earth. Only the most massive objects with the largest accelerations can produce anything we could hope to detect. The collision between two supermassive black holes is one example. Another is the most massive explosion in the history of our universe besides the Big Bang, known as inflation.
Less than a second after the Big Bang, the universe expanded by as much as 10 trillion trillion trillion times, and this expansion, referred to as inflation, generated a lot of gravitational waves. The BICEP2 team said they had observed, for the first time, a signature that they linked directly to gravitational waves from inflation.
The problem was that this signal could also be linked to cosmic dust. It sounds simple, but it's anything but. To boil it down, BICEP2 measured a kind of polarized light, which is light that has been separated into a specific energy group. You polarize sunlight every time you put on sunglasses because the sunglasses only letting the less energetic, a.k.a. darker, light to reach your eyeballs.
Inflation also polarized light. But so does dust. And it turns out that in September, a different team of researchers showed that the BICEP2 team’s results could, in large part, be explained by dust polarization. The BICEP2 team still published their results in the journal Physical Review Letters. But after an extensive peer review process, they reduced the certainty of their measurements and claims. Now teams from BICEP2 and Planck are working together to further analyze the data to determine, once and for all, if this is a discovery for the history books.