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What Is the Geometry of the Universe?
In our mind’s eye, the universe seems to go on forever. But using geometry we can explore a variety of three-dimensional shapes that offer alternatives to “ordinary” infinite space.
How the Cosmic Dark Ages Snuffed Out All Light
The recent discovery of some of the first galaxies in the universe illuminates the darkest era in cosmic history.
New Wrinkle Added to Cosmology’s Hubble Crisis
A problem confronts cosmology: Two independent measurements of the universe’s expansion give incompatible answers. Now a third method, advanced by an astronomy pioneer, appears to bridge the divide.
How Ancient Light Reveals the Universe’s Contents
A photograph of the infant cosmos reveals the precise amounts of dark matter and dark energy in the universe, leaving precious little room for argument.
The Year in Physics
Physicists saw a black hole for the first time, debated the expansion rate of the universe, pondered the origin of time and modeled the end of clouds.
No Dark Energy? No Chance, Cosmologists Contend
A study challenged the evidence for the mysterious antigravitational force known as dark energy. Then cosmologists shot back.
Top Dark Matter Candidate Loses Ground to Tiniest Competitor
Physicists have long searched for hypothesized dark matter particles called WIMPs. Now, focus may be shifting to the axion — an ultra-lightweight particle whose existence would solve two mysteries at once.
What Shape Is the Universe? A New Study Suggests We’ve Got It All Wrong
Most every cosmologist believes the universe is flat. A new analysis argues that it’s closed.
Cosmic Triangles Open a Window to the Origin of Time
A close look at fundamental symmetries has exposed hidden patterns in the universe. Physicists think that those same symmetries may also reveal time’s original secret.