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Black Hole Echoes Would Reveal Break With Einstein’s Theory
Gravitational waves have opened up new ways to test the properties of black holes — and Einstein’s theory of gravity along with them.
Why Stephen Hawking’s Black Hole Puzzle Keeps Puzzling
The renowned British physicist, who died at 76, left behind a riddle that could eventually lead his successors to the theory of quantum gravity.
How Einstein Lost His Bearings, and With Them, General Relativity
By 1913, Albert Einstein had nearly completed general relativity. But a simple mistake set him on a tortured, two-year reconsideration of his theory. Today, mathematicians still grapple with the issues he confronted.
To Test Einstein’s Equations, Poke a Black Hole
Two teams of researchers have made significant progress toward proving the black hole stability conjecture, a critical mathematical test of Einstein’s theory of general relativity.
Physicists Find a Way to See the ‘Grin’ of Quantum Gravity
A recently proposed experiment would confirm that gravity is a quantum force.
Physicists Mourn Joe Polchinski, Developer of Deep Ideas and Paradoxes
The theoretical physicist Joe Polchinski, who died February 2, left a tremendous professional and personal legacy, says a friend and collaborator.
Astronomers Trace Radio Burst to Extreme Cosmic Neighborhood
A mysterious object that repeatedly bursts with ultra-powerful radio waves must live in an extreme environment — something like the one around a supermassive black hole.
Earliest Black Hole Gives Rare Glimpse of Ancient Universe
It weighs as much as 780 million suns and helped to cast off the cosmic Dark Ages. But now that astronomers have found the earliest known black hole, they wonder: How could this giant have grown so big, so fast?
Plunge Into a (Virtual Reality) Black Hole
Join a fleet of robotic probes on a one-way virtual-reality trip into the abyss of a massive black hole.