The accelerating expansion of the universe is usually explained by an invisible force known as dark energy. But a new study suggests this mysterious ingredient may not be necessary after all. Using an ...

Scientists are on the trail of a mysterious five-particle structure that could challenge one of the biggest theories in physics: string theory. This rare particle—never seen before and predicted not ...

In 1980, Stephen Hawking gave his first lecture as Lucasian Professor at the University of Cambridge. The lecture was called “Is the end in sight for theoretical physics?” Hawking, who later became my ...