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EINSTEIN'S BIGGEST BLUNDER: Even at an optimum age of 12 billion years, the universe is too young to accommodate 14 billion-year-old stars, so even the radical step of abandoning the inflation theory might not be enough to resolve the age crisis. But there could be a solution that allows inflation to remain. All the theorists have to do is throw out another of their cherished beliefs: that Einstein was right when he repudiated his concept of a cosmological constant. Says Princeton physicist Jim Peebles: "People hate the cosmological constant. I used to hate it too. But it's something we might grow to love."
They might have to. The constant can be thought of as a kind of universe-wide repulsive force, a sort of antigravity. Einstein thought that he needed it in his general relativity theory to balance the pernicious influence of gravity. Without a cosmological constant, said the equations, the universe would have to be either contracting or expanding-which it didn't seem to be. It was only when Edwin Hubble discovered, a decade later, that it was indeed expanding that Einstein dropped the constant like a hot potato.
But particle physicists later found that a cosmological constant arose naturally from their own theories. And now cosmologists may need it to get out of the age crisis. If the constant has the right value, then cosmologists can keep inflation. The cosmos would have started out in a long period described by scientists as "loitering" or "coasting," providing stars and galaxies with ample time to form. "Then," says Sandra Faber, Primack's Santa Cruz colleague, "suddenly the cosmological constant would kick in, gunning the expansion, making it faster." Measuring a large Hubble Constant and an apparently low age today, in other words, wouldn't be a reliable indicator of what was going on earlier in the universe's lifetime. Theorists might hate Einstein's abandoned child, but, says John Huchra, an astronomer at the Harvard-Smithsonian Center for Astrophysics, "to an experimentalist it seems no more ad hoc than inflation."
THE STRUCTURE PROBLEM: At least there are some models of the cosmos-unpopular though they may be-that accommodate Freedman's age estimates. The same cannot be said for Lauer and Postman's detection of large-scale motions across the universe. Most scientists are betting that their observation is just plain wrong, but they haven't yet been able to pinpoint why. And both Lauer and Postman admit that the effect may wash out as they collect more data from deeper in space.
If it holds up, though, the theorists will have to rethink their position in a hurry. One explanation for the observation would be that galaxies are being pulled toward a concentration of mass so huge that it would make the Great Attractor look like a joke. Another might be that the Big Bang may have been lopsided, so that the universe has more energy and mass in some sectors than in others. In that case, the anomalous motion is an illusion.
But both ideas are almost impossible to reconcile with any known model of the universe. Admits Postman: "If I'd been at the receiving end of this news, I'd be skeptical too. But the modus operandi of an observer is to report what Nature is telling us." And that's true whether or not the news conforms to the conventional wisdom.