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String theorists elide a paradox about black holes by extinguishing the walls of fire feared to surround them.

Black holes occasionally reveal themselves when passing stars get ripped apart by their gravity. These tidal disruption events have created a new way for astronomers to map the hidden cosmos.

Computer simulations have become so accurate that cosmologists can now use them to study dark matter, supermassive black holes and other mysteries of the real evolving cosmos.

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.

A roundup of some of the most important discoveries gleaned so far from the Gaia space observatory’s new map of the galaxy.

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

The renowned British physicist, who died at 76, left behind a riddle that could eventually lead his successors to the theory of quantum gravity.

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.

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.