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It weighs as much as 780 million suns and helped to cast off the cosmic Dark Ages. But now that astronomers have found the earliest known black hole, they wonder: How could this giant have grown so big, so fast?
An eminent mathematician reveals that his advances in the study of millennia-old mathematical questions owe to concepts derived from physics.
Edward Witten reflects on the meaning of dualities in physics and math, emergent space-time, and the pursuit of a complete description of nature.
A number of high-energy anomalies raised hopes that astrophysicists had seen their first direct glimpses of dark matter. New studies suggest a different source may be responsible.
Astronomers are mystified by a strange star explosion in a distant galaxy that might be a relic from an earlier cosmological era.