When physicists strip neutrons from atomic nuclei, put them in a bottle, then count how many remain there after some time, they infer that neutrons radioactively decay in 14 minutes and 39 seconds, on average. But when other physicists generate beams of neutrons and tally the emerging protons — the particles that free neutrons decay into — they peg the average neutron lifetime at around 14 minutes and 48 seconds.
The discrepancy between the “bottle” and “beam” measurements has persisted since both methods of gauging the neutron’s longevity began yielding results in the 1990s. At first, all the measurements were so imprecise that nobody worried. Gradually, though, both methods have improved, and still they disagree. Now, researchers at Los Alamos National Laboratory in New Mexico have … Read the rest
In the last three decades, condensed matter physicists have discovered a wonderland of exotic new phases of matter: emergent, collective states of interacting particles that are nothing like the solids, liquids and gases of common experience.
The phases, some realized in the lab and others identified as theoretical possibilities, arise when matter is chilled almost to absolute-zero temperature, hundreds of degrees below the point at which water freezes into ice. In these frigid conditions, particles can interact in ways that cause them to shed all traces of their original identities. Experiments in the 1980s revealed that in some situations electrons split en masse into fractions of particles that make braidable trails through space-time; in other cases, they collectively whip up massless versions of themselves. A lattice … Read the rest
After a surprise discovery, astrophysicists are racing to understand superenergetic flashes of radio waves that sometimes beep out from distant galaxies. The post Inside the Hunt for the Source of a Mysterious Cosmic Burst appeared first on WIRED.… Read the rest
A classic physics experiment features a moving cart firing a ball into the air. What happens if you place the cart on an incline? The post The Wacky Physics of Firing a Ball Out of a Moving Cart appeared first on WIRED.… Read the rest
Yo-yos, glass orbs, and underwater robots on a physicist’s budget. The post At the Bottom of the Sea, Glass Spheres Prepare to Hunt for Mysterious Neutrinos appeared first on WIRED.… Read the rest
You can use Legos, pennies, beans—whatever, really—and a six-sided die to model radioactivity. Why? Because physics is fun. The post Let’s Model Radioactive Decay to Show How Carbon Dating Works appeared first on WIRED.… Read the rest