Discovery of mysterious doors suggests possibility of hidden treasuresFor years scholars have believed that the pyramid of King Khufu, largest of the three "great" pyramids at Giza, had been plundered in antiquity and everything of value, including the body of Khufu himself, had been removed. Now, Zahi Hawass, the secretary general of Egypt's Supreme Council of Antiquities and director of the Giza Plateau, suspects that might not be the case. "I really personally believe," he recently told a sold-out lecture hall in the University of Pennsylvania's Museum of Archaeology and Anthropology in Philadelphia, "that the secret chamber of Khufu is...