A prolific popularizer of science, Davies (Physics/Univ. of Adelaide, Australia; The Matter Myth, 1992, etc.) gives a broad survey of concepts of time, a subject he has become intimately acquainted with in his research. In a long ramble interspersed with biographical digressions, personal reflections, and questions from a hypothetical ``skeptic'' baffled by the quantum world, Davies discourses on concepts of time embodied in ancient cultural and religious beliefs; the Newtonian clockwork universe, in which time flows according to unbending mathematical laws; Einstein's theory that time is relative and flexible; and nonintuitive ideas from quantum mechanics. In this light, he interprets the history of human intellectual development. There have been revolutionary changes, he notes, but the story is far from over. Davies is energized by the notion that nature is permissive--that just about anything can happen if it is not forbidden by a physical law. This leads into speculations about exotic phenomena as possible consequences of relativity and quantum mechanics: black holes, strings, time warps, wormholes, time travel, alternative consciousness, and time reversal. This list of current hot topics in theoretical and experimental physics gives a realistic picture of contemporary science. A pleasant surprise is how many examples of these investigations are given from the scientific community working ``down under,'' in Australia and New Zealand. Equally enjoyable are the personal stories, including Davies's recollections of his discussions with Stephen Hawking and others. In an amusing passage, the ``chattering classes'' of British literati are savaged for their ill-considered criticism of Hawking's A Brief History of Time. But the copious epigraphs, while sometimes salient, are often irrelevant or bewildering. For readers new to the subject, Davies offers many ``believe- it-or-not'' tidbits for cocktail-party conversation; the better- informed can glean insights, cultural commentary, and late-breaking reportage on the cosmologically bizarre. (Line drawings)
