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Opinions differ about what recent measurements of a sound-trapping fluid reveal about light-trapping black holes.

Physicists have devised a holographic model of “de Sitter space,” the term for a universe like ours, that could give us new clues about the origin of space and time.

Perfect black holes are versatile mathematical tools. Just don’t mistake them for the real thing.

The same codes needed to thwart errors in quantum computers may also give the fabric of space-time its intrinsic robustness.

In the latest campaign to reconcile Einstein’s theory of gravity with quantum mechanics, many physicists are studying how a higher dimensional space that includes gravity arises like a hologram from a lower dimensional particle theory.

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

A controversial new paper argues that universes with dark energy profiles like ours do not exist in the “landscape” of universes allowed by string theory.

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.