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gravitational waves

An illustration of an extra-large black hole.
Abstractions blog

Possible Detection of a Black Hole So Big It ‘Should Not Exist’

August 28, 2019

At stake are fundamental ideas about how black holes form — and a six-way bet.

Illustration of three black holes on a starry background
Abstractions blog

To Make Two Black Holes Collide, Try Three

August 15, 2019

How do black holes merge and make gravitational waves? Maybe with a little help from their friends.

Art for "New Studies Rescue Gravitational-Wave Signal From the Noise"
gravitational waves

New Studies Rescue Gravitational-Wave Signal From the Noise

December 13, 2018

Two independent papers vanquish lingering doubts about LIGO’s historic discovery of gravitational waves.

Abstractions blog

A New Test for the Leading Big Bang Theory

September 11, 2018

Cosmologists have predicted the existence of an oscillating signal that could distinguish between cosmic inflation and alternative theories of the universe’s birth.

Illustration of a black hole with a Cauchy horizon
general relativity

Mathematicians Disprove Conjecture Made to Save Black Holes

May 17, 2018

Mathematicians have disproved the strong cosmic censorship conjecture. Their work answers one of the most important questions in the study of general relativity and changes the way we think about space-time.

Lede art for "Troubled Times for Alternatives to Einstein’s Theory of Gravity"
astrophysics

Troubled Times for Alternatives to Einstein’s Theory of Gravity

April 30, 2018

New observations of extreme astrophysical systems have “brutally and pitilessly murdered” attempts to replace Einstein’s general theory of relativity.

520px illustration for black hole echoes
Quantized Columns

Black Hole Echoes Would Reveal Break With Einstein’s Theory

March 22, 2018

Gravitational waves have opened up new ways to test the properties of black holes — and Einstein’s theory of gravity along with them.

astrophysics

Squishy or Solid? A Neutron Star’s Insides Open to Debate

October 30, 2017

The core of a neutron star is such an extreme environment that physicists can’t agree on what happens inside. But a new space-based experiment — and a few more colliding neutron stars — should reveal whether neutrons themselves break down.

Artist’s rendering of merging neutron stars.
cosmology

Colliding Neutron Stars Could Settle the Biggest Debate in Cosmology

October 25, 2017

Newly discovered “standard sirens” provide an independent, clean way to measure how fast the universe is expanding.