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Reaching for the Multiverse
Infinity and Beyond: The Ultimate Test

Multiverse Collisions May Dot the Sky

Early in cosmic history, our universe may have bumped into another — a primordial clash that could have left traces in the Big Bang’s afterglow.

Infinity and Beyond: The Ultimate Test

In a Multiverse, What Are the Odds?

Testing the multiverse hypothesis requires measuring whether our universe is statistically typical among the infinite variety of universes. But infinity does a number on statistics.


Dwarf Galaxies Dim Hopes of Dark Matter

For five years physicists have been tantalized by possible evidence of dark matter in the Milky Way’s center. But new results from small satellite galaxies have complicated the story.

statistical physics

At the Far Ends of a New Universal Law

A potent theory has emerged explaining a mysterious statistical law that arises throughout physics and mathematics.

BICEP2 graphic.

‘Big Bang Signal’ Could All Be Dust

Cosmic dust in the high latitudes of the Milky Way could account for the entire swirl pattern that had been presented as proof of a leading Big Bang theory, according to a new data analysis from the Planck satellite.

Blanco telescope.

Finding Dark Energy in the Details

The astrophysicist Joshua Frieman seeks to pinpoint the mysterious substance driving the accelerating expansion of the universe.

particle physics

Quark Quartet Fuels Quantum Feud

Newly discovered particles are forcing physicists to extend their simple picture of subatomic interactions or replace it with a more nuanced understanding.

theoretical physics

At Multiverse Impasse, a New Theory of Scale

Physicists have begun to explore the idea that mass and length may not be fundamental properties of nature. The hypothesis could help to avoid the conclusion that our world is just a weird bubble in an endlessly foaming multiverse.

Katherine Freese

In Search of Dark Stars

Katherine Freese, a physicist who will soon lead the Nordic Institute for Theoretical Physics, reflects on the hunt for dark matter and how dark matter heating may have produced the first stars.