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Nobody can say what the turmoil means-whether the intellectual edifice of modern cosmology is tottering on the edge of collapse or merely feeling growing pains as it works out a few kinks. "If you ask me," says astrophysicist Michael Turner of the Fermi National Accelerator Laboratory, near Chicago, "either we're close to a breakthrough, or we're at our wits' end."
WEIRD DATA, WEIRD THEORIES: The bewildering discoveries by Lauer, Postman, Freedman and company are only the latest in a barrage of bafflements that stargazers have had to absorb lately. Over the past few years, astronomers have uncovered the existence of the Great Wall, a huge conglomeration of galaxies stretching across 500 million light-years of space; the Great Attractor, a mysterious concentration of mass hauling much of the local universe off in the direction of the constellations Hydra and Centaurus; Great Voids, where few galaxies can be found; and galaxies caught in the throes of formation a mere billion years after the Big Bang, when they should not yet exist. "If we really trust the data," exclaims Stanford astrophysicist Andrei Linde, "then we are in disaster, and we must do something absolutely crazy."
That's a big "if." Observes David Schramm, a theoretical astrophysicist at the University of Chicago: "Whenever you're at the forefront of science, one-third of the observational results always turn out to be wrong." But this hasn't stopped the theorists from doing crazy things anyway; they've proposed one mind-stretching idea after another to explain what's going on.
One of these was inflation theory, which says the universe expanded like a balloon on amphetamines before the cosmos was one second old. Then there was cold dark matter, hypothetical subatomic particles that may account for 99% of the mass of the universe and may relegate ordinary atoms-and the stars, planets and people they make up-to the status of a cosmic afterthought. Another notion described distortions in the very fabric of space and time, going by the name cosmic strings and cosmic textures. And lately theorists have revived an old idea known as hot dark matter, and an even older one called the cosmological constant. The latter is a kind of cosmic antigravity that gives the expanding universe an extra outward push; it was first conceived by Albert Einstein himself, who then rejected it as "the greatest blunder of my life." Each of these ideas is still floating around, championed by its own corps of diehards.
In fairness, it must be acknowledged that cosmologists have had very little information to go on, at least until very recently. The distant galaxies that bear witness to the universe's origin, evolution and structure are excruciatingly faint, and it takes every bit of skill observers have to tease out their secrets. It hasn't been until the past decade, in fact, that astronomers have had powerful telescopes like the Hubble out in space and the Keck atop Hawaii's Mauna Kea, ultrafast supercomputers and super-sensitive electronic light detectors to give them the data they hunger for. In a very real sense, cosmology has only lately crossed the dividing line from theology into true science.