January 1, 2021
UChicago scientist lays out how LIGO gravitational waves could be scrambled, yielding information
There’s something a little off about our theory of the universe. Almost everything fits, but there’s a fly in the cosmic ointment, a particle of sand in the infinite sandwich. Some scientists think the culprit might be gravity—and that subtle ripples in the fabric of space-time could help us find the missing piece.
A new paper co-authored by a University of Chicago scientist lays out how this might work. Published Dec. 21 in Physical Review D, the method depends on finding such ripples that have been bent by traveling through supermassive black holes or large galaxies on their way to Earth.
The trouble is that something is making the universe not only expand, but expand faster and faster over time—and no one knows what it is. (The search for the exact rate is an ongoing debate in cosmology).
Scientists have proposed all kinds of theories for what the missing piece might be. “Many of these rely on changing the way gravity works over large scales,” said paper co-author Jose María Ezquiaga, a NASA Einstein postdoctoral fellow in the Kavli Institute for Cosmological Physics at the UChicago. “So gravitational waves are the perfect messenger to see these possible modifications of gravity, if they exist.”