Astronomers are a step closer to cracking one of the secrets of dark energy—the mysterious force believed to be causing the universe's accelerated expansion.

This investigation examines the multiverse theory, exploring whether parallel universes could truly exist. Scientists weigh the evidence, from quantum mechanics to cosmic ...

For much of the twentieth century, scientists expected the expanding universe to slow over time. The opposite turned out to be true. Space is stretching faster today than in the past, and the precise ...