LIVINGSTON — More than a billion years ago, two black holes collided and merged, creating gravitational waves that until now scientists could only theorize about.
On Thursday, a team of scientists working in Livingston Parish and Washington state announced the first-ever recorded detection of those waves, confirming a major prediction of Albert Einstein’s general theory of relativity and opening a new window into the universe.
It was the first direct detection of gravitational waves and also the first observation of a binary black hole merger, officials with the Laser Interferometer Gravitational-wave Observatory said.
The announcement also confirmed the accuracy of rumors that started swirling almost as soon as the work to detect the waves began in September.
The gravitational waves — which Einstein predicted in 1916 but believed would never be detected — were recorded by the Advanced LIGO detector in Livingston at 4:51 a.m. on Sept. 14, 2015. Seven milliseconds later, LIGO’s twin detector in Hanford, Washington, recorded the same signal.
The detectors had been nearing the end of a five-year period of upgrades and fine-tuning and were not scheduled to officially begin work for another four days, on Sept. 18.
William Parker, a Southern University graduate with an advanced degree in mathematics/physics, was at the helm in the Livingston control room and first noted the anomaly.
“At first I was just calm, but as the calls piled up and we began the process of verification, I was excited and very contemplative,” Parker said.
Many of the staff members feared it was only a blind injection, a process where an authorized LIGO official secretly inserts a signal into the system to test the scientists’ response and analysis, said Senior Staff Specialist Brian O’Reilly, of the California Institute of Technology.
They had reason to be suspicious: the scientists thought they had detected gravitational waves in 2010, just before they stopped work with the old detector system to install the upgraded equipment, but that turned out to be a blind injection.
An 11 a.m. teleconference with the Hanford observatory eliminated that possibility this time, O’Reilly said. There had been no blind injection.
“That’s when I had my eureka moment,” O’Reilly said. “There was a noticeable change in the room. Everybody was already taking it seriously, but that was when we realized this was no test. This was a reality.”
Joseph Giaime, head of the Livingston observatory and a professor of physics and astronomy at LSU, was more skeptical. He called LIGO spokeswoman and LSU colleague Gabriela Gonzalez for confirmation.
“I wanted to make sure no one had authorized some kind of double-blind injection or something,” Giaime said.
Scientists with the LIGO Scientific Collaboration and colleagues from the VIRGO Collaboration in Europe worked together to analyze the data, Gonzalez said.
The signal’s changes in frequency and amplitude carried valuable information about the cataclysmic event that had created the waves.
The scientists determined the waves had come from the merger of two black holes — 29 and 36 times the mass of the sun — roughly 1.3 billion years ago, Gonzalez said.
The collision gave off about 3 solar masses worth of energy in the form of gravitational waves.
The frequencies of these waveforms are within human hearing range, Gonzalez said.
“We can hear gravitational waves. We can hear the universe,” she said. “That’s one of the beautiful things about this. We are not only going to be seeing the universe. We are going to be listening to it.”
Thursday’s announcement was hailed by scientists as a major breakthrough. Renowned physicist Stephen Hawking called the news “thrilling,” posting his congratulations to the LIGO team on Facebook.
The discovery will offer scientists a new way of exploring the universe, pairing gravitational wave astronomy with other means of observation.
“This is big because what’s going to come now is we’re going to be able to hear more of these things,” said David Reitze, executive director of the LIGO Laboratory at Caltech. “And no doubt, we’ll hear things that we expected, like black holes or binary neutron stars, but we will also hear things that we never expected.”
Rainer Weiss, one of the cofounders of LIGO and an emeritus professor of physics at the Massachusetts Institute of Technology, said Einstein had theorized that space-time was distorted but was despondent that gravitational waves could ever be detected.
“If all this technology had been available to Einstein in 1915, I bet he would have invented LIGO,” Weiss said. “He was smart enough, and he knew physics. He wasn’t just a theorist.”
Kip Thorne, another LIGO cofounder and emeritus professor of theoretical physics at Caltech, said LIGO was a project that had been more than half a century in the making.
Weiss and others developed the key ideas for the interferometer detectors about 45 years ago, and the National Science Foundation began funding pre-LIGO research and development about 35 years ago. Construction of the two detectors did not begin until about 20 years ago.
“We begin with a high-risk dream, but with a very high potential payoff,” Weiss said. “And we are here today with a great triumph, a whole new way to observe the universe.”
France Cordova, director of the National Science Foundation, congratulated the team on their hard work and accomplishments.
“Einstein would be beaming, wouldn’t he?”
Follow Heidi R. Kinchen on Twitter, @HeidiRKinchen, and call her at (225) 336-6981.