Einstein’s claim that the speed of light is constant has survived more than a century of scrutiny—but scientists are still ...

But there are several important anomalies, including a widely debated one called the Hubble tension. It is named after Edwin ...

Nearly a century after Albert Einstein and Niels Bohr turned a technical disagreement into a philosophical duel, a new ...

Albert Einstein was intrigued by a simple puzzle: an old car must travel 2 miles at an average of 30 mph. The twist? Its structure makes the solution impossible. Can you solve it?

For a generation, cosmologists have treated dark energy as a fixed backdrop, a steady pressure stretching space faster and ...

Since Einstein, physicists have found that certain entities can reach superluminal (that means "faster-than-light") speeds and still follow the cosmic rules laid down by special relativity.

KEY OBSERVATIONS Light from a dead star exploded ten billion years ago, yet it reached Earth not once, but several times, ...

China builds a record-breaking hypergravity machine to compress space and time, accelerating science, engineering, and ...

Scientists are a step closer to solving one of the universe's biggest mysteries as new research finds evidence that two of ...

For centuries, the principle of symmetry has guided physicists towards more fundamental truths, but now a slew of shocking findings suggest a far stranger idea from quantum theory could be a deeper dr ...

Physicists in China have brought one of Einstein’s thought experiments into reality—but not quite with the outcome he hoped ...