How is the total mass of the universe calculated? Bob GiddingsGreen Bay, Wisconsin Calculating the total mass of the universe ...

That cosmologists cannot agree on one of the most elementary facts about the universe is striking enough. But that uncertainty produces others, too: it makes it impossible to calculate an exact age ...

“There’s a lot of meanings for ‘small,’” says Janet Conrad, a particle physicist at the Massachusetts Institute of Technology ...

An artistic illustration of the mechanism proposed by Professor Stefano Profumo where quantum effects near the rapidly expanding cosmic horizon after the Big Bang gravitationally generate dark matter ...

Nearly half of the universe’s ordinary matter has been hiding — until now. Bursts of radio waves have illuminated the whereabouts of all ordinary matter, revealing its distribution between, around and ...