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Since the 1970s, physicists have described black holes using borrowed versions of the laws of thermodynamics. But are black holes really thermodynamic systems? Craig Callender worries that the analogy has been stretched too far.
Lurking behind Einstein’s theory of gravity and our modern understanding of particle physics is the deceptively simple idea of symmetry. But physicists are beginning to question whether focusing on symmetry is still as productive as it once was.
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.