Life Helps Make Almost Half of All Minerals on Earth

A new origins-based system for classifying minerals reveals the huge geochemical imprint that life has left on Earth. It could help us identify other worlds with life too.

The New Neutron Star in Andromeda

Mass and Angular Momentum, Left Ambiguous by Einstein, Get Defined

Surprising as it may sound, 107 years after the introduction of general relativity, the meanings of basic concepts are still being worked out.

Controversy Continues Over Whether Hot Water Freezes Faster Than Cold

Decades after a Tanzanian teenager initiated study of the “Mpemba effect,” the effort to confirm or refute it is leading physicists toward new theories about how substances relax to equilibrium.

How to Make the Universe Think for Us

Physicists are building neural networks out of vibrations, voltages and lasers, arguing that the future of computing lies in exploiting the universe’s complex physical behaviors.