Physicists have created a new computer code that could speed up the design of the complicated magnets that shape the plasma in stellarators, making the systems simpler and more affordable to build.

Valued at $1.6 billion, a tiny start-up called Axiom is building A.I. systems that can check for mistakes. Valued at $1.6 billion, a tiny start-up called Axiom is building A.I. systems that can check ...