What's up in
gravity
Abstractions blog
Researchers Check Space-Time to See if It’s Made of Quantum Bits
The newly developed theory of emergent gravity, proposed as an alternative to dark matter, struggles in one of its first trials.
quantum gravity
Where Gravity Is Weak and Naked Singularities Are Verboten
Recent calculations tie together two conjectures about gravity, potentially revealing new truths about its elusive quantum nature.
Thinking Places
Rainer Weiss, Remembering the Little Room in the Plywood Palace
The physicist who designed the LIGO experiment that detected gravitational waves still holes up in a small basement lab surrounded by electronics and optical instruments.
dark matter
Dark Matter Recipe Calls for One Part Superfluid
A different kind of dark matter could help to resolve an old celestial conundrum.
gravity
The Case Against Dark Matter
A proposed theory of gravity does away with dark matter, even as new astrophysical findings challenge the need for galaxies full of the invisible mystery particles.
astrophysics
Colliding Black Holes Tell New Story of Stars
Just months after their discovery, gravitational waves coming from the mergers of black holes are shaking up astrophysics.
astrophysics
After Black Holes Collide, a Puzzling Flash
A satellite spotted a burst of light just as gravitational waves rolled in from the collision of two black holes. Was the flash a cosmic coincidence, or do astrophysicists need to rethink what black holes can do?
Q&A
From Einstein’s Theory to Gravity’s Chirp
The path from a revolutionary set of equations to the detection of gravitational waves was strewn with obstacles and controversy, explains the physicist Daniel Kennefick — and the struggle continues.
astrophysics
Gravitational Waves Discovered at Long Last
Ripples in space-time have been detected a century after Einstein predicted them, launching a new era in astronomy.