Quantum Entanglement

Quantum entanglement allows two objects to affect each other’s behaviour instantly across vast distances — what Albert Einstein called “spooky action at a distance”. But by how much? The answer could be incalculable, says a team of 5 researchers in a 165-page preprint. In one fell swoop, their proof solves a number of related problems in pure mathematics, quantum mechanics and a branch of computer science known as complexity theory. If it holds up, “it’s a super-beautiful result” says theoretical quantum physicist Stephanie Wehner.

Mysterious radio signal tracked to its source

A second example of a repeating fast radio burst (FRB) has been traced to its origin — a nearby, “fairly ordinary” spiral galaxy. FRBs last for only milliseconds, making them incredibly difficult to trace — only four have been localised, including one other repeating one. The newly measured FRB’s home galaxy is quite different from those of the other four, deepening the mystery of what causes the extragalactic signals.

Earth-sized planet found in its star system's habitable zone

Astronomers have discovered a world only a little bit bigger than Earth that orbits in a nearby star’s habitable zone — the region in which liquid water could exist. Astronomers have identified only a handful of such exoplanets. The world orbits a star about 31 parsecs from our planet, and is the first such body to be discovered by NASA’s Transiting Exoplanet Survey Satellite, which launched in 2018. Although the world is similar in size to Earth — and could be rocky — astronomers say it is likely to be very different from our planet because the light in which it is bathed is fainter.