For centuries, men and women have pondered how the stars were called forth. The Roman poet Lucretius assumed the universe to be eternal: How could there ever have been a condition without existence? Theology spoke of a discrete beginning: the book of Genesis reflecting the ancient Hebrew view of six days of cosmic toil; the fourth-century Christian thinker Augustine supposing that time as well as space was created by God at the first moment; the 12th-century Islamic rationalist al-Ghazali asserting that since an infinite past seems incomprehensible, the universe must have begun at a specific point.
But while thinkers have often engaged the question of whether the cosmos is newly formed or unfathomably old, few have speculated on the head-spinning topic of what might have come before creation. Copernicus, Newton, Einstein, and others viewed the heavens as an immutable realm whose physical laws could be discovered but about whose origin all clues had long since vanished. Just as clergy may prefer to sidestep the issue of what caused God, the issue of what caused the universe has often been one the science world would rather skip.
Yet substance and light swirl around us: They must have arisen from some source. Recently, aided by a bonanza of information from the Hubble Space Telescope, prominent scientists have begun to explore what might have preceded the current universe. Alan Guth, a cosmologist at the Massachusetts Institute of Technology, says that "the enigmas of creatio...