
Neutron Stars: Nature’s Weirdest Form of Matter
The insides of neutron stars—the densest form of matter in the universe—have long been a mystery, but it is one that scientists are starting to crack

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Neutron Stars: Nature’s Weirdest Form of Matter
The insides of neutron stars—the densest form of matter in the universe—have long been a mystery, but it is one that scientists are starting to crack

The Puzzle of the First Black Holes
Astronomers are puzzled about how the oldest supermassive black holes could have grown so big so early in cosmic history

Can Quantum Mechanics Save the Cosmic Multiverse?
A surprising connection between cosmology and quantum mechanics could unveil the secrets of space and time

How Does the Quantum World Cross Over?
The universe according to quantum mechanics is strange and probabilistic, but our everyday reality seems nailed down. New experiments aim to probe where—and why—one realm passes into the other

Loopy Particle Math
Scientists are creating mathematical tools to identify novel particles and phenomena at the world's largest particle accelerator

The Neutrino Puzzle
The largest experiment ever to probe these mysterious particles could point the way to new physics

Is Dark Matter Real?
Astrophysicists have piled up observations that are difficult to explain with dark matter. It is time to consider that there may be more to gravity than Einstein taught us

Is Dark Matter Made of Black Holes?
A hidden population of black holes born less than one second after the big bang could solve the mystery of dark matter

Lost in Thought—How Important to Physics Were Einstein’s Imaginings?
Einstein’s thought experiments left a long and somewhat mixed legacy of their own

Searching for the Dark: The Hunt for Axions
The Axion Dark Matter Experiment just entered the most sensitive phase yet in its search for invisible particles to explain the universe's hidden mass

Beautiful Physics: The Search for New Particles at LHCb
The Large Hadron Collider beauty experiment has seen hints of new particles that may point the way toward a higher theory of physics

Spooky Quantum Action Passes Test
Recent experiments quash the hope that the unsettling phenomenon of quantum entanglement can be explained away

World’s Fastest Movies Capture Molecules in Motion
New movies of drug proteins or photosynthesis in action, shot in millionths of a billionth of a second, show how the molecules work—or fail

Does Einstein’s Theory of Gravity Hold Near Black Holes?
General relativity has never been tested in places where the effects of gravity become truly extreme—for example, at the edge of a black hole. That will soon change

String Theory May Create Far Fewer Universes Than Thought
Some physicists claim that the popular landscape of universes in string theory may not exist

Here Come the Waves
After a clutch of historic detections, gravitational-wave researchers have set their sights on some ambitious scientific quarry