which has been designed with a little hole at the top to let the tip of the umbrella through and a slit at the bottom to reveal the opener button. And, most crucial of all, she stays ...

But a more radical solution has also been floated: a European “nuclear umbrella.” If the United States has always been Europe’s big brother, France and the United Kingdom are longstanding ...

What Are Black Hole Supermazes? Supermazes come from M-theory, an umbrella idea that includes multiple versions of string theory, in which our universe contains 11 dimensions—not just the four ...