Word: loebs
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...however, even the mightiest telescopes haven't been able to penetrate into that murky era. "We have a photo album of the universe," says Avi Loeb, a theoretical astrophysicist at Harvard University, "but it's missing pages--as though you had pictures of a child as an infant and then as a teenager, with nothing in between...
...crude, but a series of increasingly sophisticated instruments, culminating in the Wilkinson Microwave Anisotropy Probe (WMAP) satellite in 2003, have laid bare the structure of the 400,000-year-old cosmos--only a few hundred-thousandths of its present age--in surprising detail. This was the baby picture Loeb referred to. At that point, the universe was still a very simple place. "You can summarize the initial conditions," says Loeb, "on a single sheet of paper." Some regions were a tiny bit denser than average and some a little more sparse. Most of the stuff in it--then and still...
...That's because hydrogen-gas clouds are nearly opaque to visible light; no ordinary telescope will ever be able to see what happened afterward. Yet somehow the matter that started as a sea of individual atoms managed to transform itself into something more. So back in the early 1990s, Loeb began lobbying theorists to make a major push to deduce through computer simulations how the first stars formed. The plan was to re-create the young universe digitally, plug in equations for the relevant physics and see what must have happened...
...different periods in the Dark Ages. When you map cosmic hydrogen at, say, 50 million years after the Big Bangbefore the first stars had a chance to formthen at 100 million, 200 million or half a billion years later, you get a series of snapshots. Combine them, says Loeb, and "you'll be able to make a 3-D picture of hydrogen gas as the universe evolves. At some point, you'll start to see holes, like Swiss cheese," as the gas clouds become ionized and transparent. Precisely how the holes grow and merge over time will help determine whether...
...DARK AGES The death of the mega-stars triggered the formation of normal stars, creating the first recognizable dwarf galaxies. Their radiation in turn burned through the remaining shrouds of hydrogen, bringing the dark ages to a close TIME Graphic by Joe Lertola Sources: Professor Avi Loeb, Harvard University; Professor Richard Ellis, Caltech...