杏吧原创

AS Shelley declaims in Hellas: 鈥淭he World鈥檚 great age begins anew,/The golden years return,/The Earth doth like a snake renew/Her winter weeds outworn.鈥�

The oldest mythologies dwell on cosmic and theistic issues, and Paul Halpern shows in The Cyclical Serpent that modern cosmology has much in common with the endless dance of Siva and the cult of Ouroboros, the self-eating serpent. The birth and death of the Universe parallel the birth and death of individual life, and many of the riddles of modern cosmology seem to repeat the riddles of mythology. The question of whether the Universe will end in fire or ice becomes the question: is omega greater or less than unity?

The answer depends on solving the missing mass problem. Halpern writes: 鈥淗umankind will scarcely be content until it has conquered the mysteries of space and time, and has learned from where it has come and to where it is going. This book ponders one possible answer to these riddles.鈥� His answer is that the Universe constantly renews itself and has no beginning or end.

Almost certainly, however we interpret the known facts, our answers to the cosmic riddles will turn out to be wrong. History teaches us this, if nothing else. Yet Halpern鈥檚 story, nonetheless, is entertaining and informative. The Cyclical Serpent opens with a foreword by the Russian physicist Andrei Linde that presents a brief summary 鈥� full of insight 鈥� of recent developments in cosmology. Then Halpern lays forth his theme of endless return in the form of a recurrent Universe. He unfolds this theme to show how modern developments support the notion of cosmic recurrence. It is an engrossing idea and you do not have to agree with every point to enjoy the tale he tells.

The history of the idea of eternal return is discussed briefly in 鈥淭he Tradition of Cycles鈥�. The bases of modern cosmology 鈥� expansion, homogeneity, inflation 鈥� receive attention in 鈥淭he Modern View of the Cosmos鈥�. Halpern鈥檚 terminology is lucid and often colourful. The big bang is a 鈥渟izzling broth of particles鈥� and the microwave background radiation is the 鈥渉iss of the great serpent鈥�. Part three, 鈥淭he Quest for Our Universal Destiny鈥�, delves into interesting but often speculative subjects, and ends with discussions on topics such as everlasting life, bubble universes and the meaning of it all. To judge by Halpern鈥檚 book, modern cosmology shirks nothing.

Cosmology is always exciting. The excitement, however, is in the ideas, not in the cosmologists. Many authors of popular accounts of cosmology have sensationalised cosmology, portraying it as a scene of frenetic action, with charismatic actors, skilled in the arts of verbal combat, rushing here, there and everywhere. The melodrama of action upstages the quiet drama of thought.

The Cyclical Serpent, however, as much as is possible in a popular work, keeps the excitement in the ideas and not the cosmologists. I recommend this book to all who ponder the ancient riddles.