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cosmology

astrophysics

The Particle That Broke a Cosmic Speed Limit

May 14, 2015

Physicists are beginning to unravel the mysteries of ultrahigh-energy cosmic rays, particles accelerated by the most powerful forces in the universe.

The Quantum Fabric of Space-Time

Interactive: What Is Space?

April 30, 2015

Imagine the fabric of space-time peeled back layer by layer.

The Quantum Fabric of Space-Time

How Quantum Pairs Stitch Space-Time

April 28, 2015

New tools may reveal how quantum information builds the structure of space.

The Quantum Fabric of Space-Time

Wormholes Untangle a Black Hole Paradox

April 24, 2015

A bold new idea aims to link two famously discordant descriptions of nature. In doing so, it may also reveal how space-time owes its existence to the spooky connections of quantum information.

Physics

Dark Energy Tested on a Tabletop

March 31, 2015

Is dark energy a cosmic chameleon that can fade into its surroundings? A recent test brings the mysterious anti-gravitational force down to earth.

cosmology

Joint Dust Analysis Deflates Big Bang Signal

January 30, 2015

No definitive evidence for cosmic inflation is found, but support remains strong for the theory even as critics highlight its shortcomings as an explanation for how and why the universe began.

Reaching for the Multiverse
Infinity and Beyond: The Ultimate Test

Multiverse Collisions May Dot the Sky

November 10, 2014

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?

November 3, 2014

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.

astrophysics

Dwarf Galaxies Dim Hopes of Dark Matter

October 25, 2014

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.