Are We Alone In The Universe / Renewing Our Search For Alien Intelligence
Illustrated. 242 pages. Allen Lane. $15.82 – $17.82 [Buy from Amazon.com].
There are two subtitles for different editions of this fine book by Paul Davies. Subtle promotional reasons most likely dictated the variance for different markets, but ‘Renewing Our Search for Alien Intelligence’ is truer to the theme of the book. Published for the 50th anniversary of SETI, Davies, one of the best cosmological science writers of our day, uses this work to challenge the assumptions of the search for extraterrestrial intelligence.
‘How could something as bold and visionary as SETI become conservative?’ Davies asks in the first chapter. His answer: anthropocentrism (and later, what you might call ‘radiocentrism’). There’s a great sequence in the first chapter of examples of scientists basing their work on assumptions that stem from their own preoccupations, although I suppose that potential xenoarchaeologists aren’t immune to this.
As you’d expect from someone with such experience in translating profound concepts for a general audience, the book offers an accessible introduction to SETI, the history of the extraterrestrial life debate, an overview of astrobiology (including an interesting chapter on the search for a second ‘shadow biosphere’ on Earth) and the Drake Equation. Towards the end there’s an overview of how we might response to first contact (Davies is chair of the SETI Post-Detection taskgroup in the International Academy of Astronautics).
But it’s the middle of the book, from chapter 5 onward that Davies sets himself up as a SETI iconoclast:
‘The traditional approach to SETI is based on the belief that alien civilizations are targeting Earth with narrow-band radio messages. But in my opinion, this ‘central dogma’ simply isn’t credible.’
This doesn’t seem too iconoclastic to me – Davies gives an overview a number of alternate SETI programs: neutrino messaging, beacons, probes, nanoprobes, Allen Tough’s IETI program and even genetically-tailored microbe probes, all ideas which have been around for a while I think, but which are perhaps gaining some acceptance because of the ‘eerie silence’ which ‘prompts us to re-evaluate […] and consider other ways an alien intelligence might leave identifiable traces.’
Davies sees this new paradigm as akin to forensics, but it seems archaeological to me (of course):
‘The universe is a rich and complex arena in which signs of alien intelligence might be buried amid a welter of data from natural processes, and unearthed only after some ingenious sifting.’
The Solar System appears primordial, but Davies asks us to consider what anomalies, what remains or what absences, we might find that could point in the direction of palaeocontact. Further: what signs of alien super technology or astroengineering might we be able to detect at great distances? These are signs that a carefully constructed SETI experiment can search for that don’t rely on a signal being deliberately targeted – they are simply the result of an alien civilization going about its routine activities.
Again, these ideas aren’t particularly new, they’ve been floating around for a while in the alternative SETI community. But it’s good to see it receiving serious and mainstream attention.
In summary, The Eerie Silence is a good introduction to SETI with a slant towards non-traditional methodology, which includes some of the main space archaeology fields.
A lot of it I’d seen elsewhere, but the book is aimed at a general audience. Still, if you have a deeper interest in SETI it’s worth reading, although you might find yourself wishing for some more detail in places. There’s a chapter on postbiological intelligence, for example, which I was disappointed to see made no mention of Steven J. Dick except in a footnote. Dick is synonymous with that paradigm (in my mind anyway).