When matter was new in the universe, it was an exotic gas whose components later congealed into the more-ordinary matter made of atoms. At least, that was the story. Now, physicists trying to re-create that gas in an accelerator say that the universe's original stuff appears to have been a liquid.
Like the gas that had been expected, the ur-liquid the physicists made is ultrahot and ultradense—up to 150,000 times as hot as the sun's core and 100 times as dense as ordinary atomic nuclei.
It's essentially a sample of primordial matter from the explosive birth of the universe, Samuel Aronson of Brookhaven National Laboratory in Upton, N.Y., said at a press conference Monday in Tampa, Fla., at a meeting of the American Physical Society. "We think we're looking at a phenomenon last seen in the universe more than 13 billion years ago," he says.