Cosmologists are becoming increasingly confident of their ability to fathom the secrets of the universe. Indeed there are scientists who believe that the cosmologists are too cocky. Last week in Nature, the University of London's William Hunter McCrea examined cosmology with a mathematician's skeptical eye. His conclusion: a built-in mystery to the universe will forever keep cosmologists from knowing what it is really like.
The root of the problem, says McCrea. is that light does not travel at infinite speed, and other influences such as gravitation are presumably just as slow. So when...