Physics

The surprising discovery of a massive, Milky Way–size galaxy that is made of 99.99 percent dark matter has astronomers dreaming up new ideas about how galaxies form.

String theory has so far failed to live up to its promise as a way to unite gravity and quantum mechanics. At the same time, it has blossomed into one of the most useful sets of tools in science.

The first star map from the ESA’s Gaia space telescope is poised to revolutionize our understanding of the Milky Way galaxy.

What insights can an LCD display give us about time's arrow?

How do scientists react to major breaking science news? For astrophysicists after the big gravitational waves announcement, it was meeting for two weeks in Santa Barbara, California.

Just months after their discovery, gravitational waves coming from the mergers of black holes are shaking up astrophysics.

The astrophysicist Tracy Slatyer is searching for faint wisps of dark matter annihilating in the early universe — and perhaps in hiding places closer to home.

A discrepancy in the measured size of the “deuteron” increases the chance that something is amiss in our understanding of atoms.

Physicists are confronting their “nightmare scenario.” What does the absence of new particles suggest about how nature works?