Simply put, gravitational waves are distortions in the fabric of space-time due to a massive cosmological event. The gravitational waves first detected in 2015 were caused by two giant black holes spiraling inward toward each other and then eventually colliding.
When black holes spiral, gravitational waves periodically radiate from their center of motion, leading to a final burst of gravitational waves when they merge.
In the waves detected in 2015, four sets of gravitational waves have been detected from black hole collisions and one from what could be a neutron star collision. Different versions of the Laser Interferometer Gravitational-Wave Observatory (LIGO) are being built and operated all over the world.
As it turns out, Albert Einstein had predicted gravitational waves as a consequence of general relativity in the 1920s. Nevertheless, after 20-odd years of arguing with himself and with other prominent scientists, he concluded that gravitational waves couldn’t exist because they couldn’t carry energy.
A few decades later, in 1957, Richard Feynman argued that they could exist, setting the stage for the discovery of energy-carrying gravitational waves almost 60 years later.
Then, in 1968 at the University of Maryland, Joseph Weber created the Weber bar, which evolved over the following years into the complex series of mirrors and perpendicular arms that is LIGO.
I remember when the discovery of gravitational waves was announced. I had physics section, which the students and the TAs collectively decided to skip in order to go downstairs, where some professors had put the broadcast up on a big screen. We watched the mesmerizing animation of the black holes spiraling toward each other.
There was a lot of thanking: of Einstein’s genius, of Weber’s resourcefulness, of the people who believed in the idea enough to fund the creation of LIGO. But the names that stood out the most were Barry Barish, Kip Thorne and Rainer Weiss, the physicists who would win the Nobel Prize a little over a year later.
The first inspiration for LIGO occurred 45 years ago. Unable to figure out how to explain gravitational waves to his students, Weiss thought up the idea for LIGO.
He constructed an experiment, which he later realized could eventually become a very real way of detecting gravitational waves.
After Weiss interacted with Thorne, Thorne also started to believe in the idea. Thorne proved to be instrumental in convincing Caltech to create the gravitational wave research group led by Ron Drever.
Later in 1994, Barish joined as the LIGO principal investigator, and the depth of his knowledge and practicality helped LIGO turn into something that could detect the tiny space-time fluctuations that gravitational waves are by the time they reach us.
By the time of the 2016 press conference, Drever was already very sick, and he passed away before the Nobel Prize was awarded. It was a struggle, and these four scientists were in it for the long haul.
If they had given up on their idea or if they hadn’t followed it through, none of this would have been possible.
But, then again, there was a lot of people involved in the discovery: hundreds, maybe even more. It’s possible that the discovery may never have happened if you take any of these people out of the equation.
What if that confused student in Weiss’ physics class, whose name we don’t know, hadn’t spoken up about how they were confused about gravitational waves?
What about the people who helped develop the machinery for LIGO? What about the physicists Felix Pirani and Hermann Bondi? You probably haven’t heard their names, but they were instrumental in convincing the world that gravitational waves could in fact carry energy.
What about the people whose names and whose contributions we aren’t even aware of that we don’t know about?
On the morning the Nobel Prize was announced, one of my physics professors told us he was involved in gravitational-wave research as an undergrad. Looking back on it now, he had no idea what the research would come to.
And that’s something I think a lot of us can relate to.
I work in a research lab at Hopkins, and it’s doing some really big things. But, sometimes, it’s hard for me to fully comprehend the bigger picture. I just have my little project and my little task. I zero in on my little goal, and I achieve it.
Scientific milestones are filled with hundreds, even thousands, of people like that — people who are a small piece of the puzzle but a piece nonetheless, people whose names will never show up in the headlines but were still there, still part of it.
That’s one of the things I love about the scientific community today. Everything is a collaboration : from our freshman year problem sets to the meetings in my lab where we conference call NASA and a university in Chile.
You only see three names in the headlines, but just remember that it’s only because those headlines couldn’t fit the hundreds of people who contributed, who matter.