Recent reports that the universe may be significantly younger than previously thought have sent scientists back to the drawing boards and challenged some of their most settled notions about the size and structure of the cosmos.
Last month a team of researchers working with the Hubble Space Telescope reported that calculations derived from a new measurement of the distance to the spiral galaxy M100 -- some 56 million light years from the Sun -- suggests the universe may be no more than 8 billion to 12 billion years old, rather than previous estimates of 15 billion to 20 billion years.
The finding implies a startling paradox, because the oldest stars are thought to be at least 16 billion years old. That would make them older than the universe of which they are a component part -- an apparent logical impossibility.
It may be that the yardstick scientists use to determine stellar distances is flawed, or that stars evolve more rapidly than present theories allow. These are the first questions scientists are likely to ask in trying to explain the seemingly contradictory results. Yet the history of scientific progress strongly suggests that when new knowledge uncovers an apparent paradox of this magnitude, an entirely new theory of reality often is required to resolve matters. The latest findings may point to just such a scientific crossroads.
One promising approach, for example, is described in an article by Stanford University physicist Andrei Linde in the November issue of Scientific American. Mr. Linde presents his theory of an "inflationary universe" -- a cosmos that for a brief instant expands at a rate faster than the speed of light -- as one scenario in which all creation can be described as a self-generating "fractal," or fractionally dimensional space. Such a universe would continually reproduce itself throughout eternity, rather than originate in a single "big bang."
Among the more bizarre predictions of Mr. Linde's theory are that the heavens we observe are only a tiny fraction of all creation and that the laws of physics in distant regions of the cosmos may be completely different from the ones that operate in our corner of the universe. Such speculations amount to a radically new conception of physical reality that goes far beyond the wildest imaginings of science fiction writers. If history is any guide, we may be on the verge of a revolution in scientific thought comparable to the changes wrought by Newton and Einstein that made the unthinkable commonplace and the fantastic part of our everyday concept of the way things are.