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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.
Newly discovered “standard sirens” provide an independent, clean way to measure how fast the universe is expanding.
Physicists theorize that a new “traversable” kind of wormhole could resolve a baffling paradox and rescue information that falls into black holes.
Astronomers have for the first time matched a gravitational-wave signal to a kilonova’s burst of light, observations that will “go down in the history of astronomy.”
Repeating radio bursts are among the most mysterious phenomena in the universe. A new theory explores how some of their puzzling properties can be explained by galactic lenses made of plasma.
The universe has not cooperated with physicists’ hopes. In desperation, many are looking for new ways to search for surprises at the Large Hadron Collider.
Reductionism breaks the world into elementary building blocks. Emergence finds the simple laws that arise out of complexity. These two complementary ways of viewing the universe come together in modern theories of quantum gravity.
Physicists are trying to rewrite the axioms of quantum theory from scratch in an effort to understand what it all means. The problem? They’ve been almost too successful.