When black holes collide, the collision creates ripples in the fabric of space-time – gravitational waves. These distortions propagate deep into the universe, but by the time they reach Earth, they have become faint, making them extremely difficult to detect. Thanks to a global network of observatories—the Laser Interferometer Gravitational-Wave Observatory (LIGO), Virgo, and the Kamiokande Gravitational-Wave Detector (KAGRA)—scientists have discovered dozens of these tiny wobbles in space-time. Now, the collaboration has released its latest dataset, more than doubling the number of tests.
The results suggest that our universe is undergoing a cosmic collision. Some of the waves originate from the collision of a pair of black holes, others appear to come from a colliding black hole and a neutron star (the dense, dead core of a massive star), and from two neutron stars colliding together.
The new catalog also reveals a wider variety of known black holes, including some that appear to be unbalanced and others that spin extremely fast. Overall, the observations are “remarkable,” said Zsuzsanna Márka, an associate research scientist at Columbia University who was involved in the LIGO-Virgo-KAGRA collaboration.
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Ryan Nowicki/Bill Smith/Karan Jani/LIGO-Virgo-KAGRA/Vanderbilt University/EMIT/NSF
“We’re really pushing the envelope and seeing objects that are more massive, rotating faster, more astrophysically interesting and unusual,” Daniel Williams, a researcher at the University of Glasgow and a member of the collaboration, told MIT News.
The expanded detection set allows astronomers to test Albert Einstein’s general theory of relativity, which states that gravity is a geometric property of space-time.
Szabolcs Márka, a physics professor at Columbia University who worked at LIGO and is married to Zsuzsanna Márka, said doing so could help achieve the field’s Holy Grail. “What lies beyond Einstein’s general theory of relativity? Large catalogs are paving the way for a deeper understanding of these mysteries,” he said.
According to the theory, mass distorts the shape of spacetime, causing objects to travel on curved paths near heavy masses. The gravitational waves produced by these cosmic collisions will reveal new details about this distortion that could confirm or challenge the predictions of Einstein’s theory.
Details will be given in the catalog Astrophysical Journal Letters, The journal recently published a paper about it online. The Markas say it will soon be possible to release real-time data from the collaboration.
“Each new detection of gravitational waves allows us to unlock another piece of the cosmic puzzle in a way that we couldn’t just a decade ago,” Lucy Thomas, a co-author of the paper and a postdoctoral researcher at Caltech’s LIGO laboratory, told MIT News. “It’s incredibly exciting to think about what astrophysical mysteries and surprises we might uncover with future observing runs.”
