The largest-ever 3D map of the cosmos hints that the dark energy that’s fueling the universe’s expansion may be weakening. One community of theoretical physicists expected as much. On the morning of ...

“Dark energy” is a term scientists use to refer to whatever is causing the universe to expand faster over time. We don’t know exactly what dark energy is—no one has ever directly seen or measured ...

Researchers have compiled all of the available evidence on the mysterious nature of dark energy. Their conclusion? While there are hints that it may be "phantom," its true nature remains frustratingly ...

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