Paul Davies is a well-known physicist, lately of Arizona State University, and also chair of the SETI Post-Detection Taskgroup. (SETI = Search for Extraterrestrial Intelligence). In this nonfiction text, he explains to a general audience what SETI is and attempts to answer the famous question of Enrique Fermi about ETs: “Where is everybody?”
Despite decades of listening for signals from the stars, we have heard nothing but silence. Why?
Several equally plausible answers come to mind. Maybe nobody is out there, and humans are the only intelligent life form in the universe. That would certainly explain the silence.
Another possibility is that ET is out there but has not signaled, or, has sent signals that we have missed so far, so keep listening.
The most likely explanation, it seems to me, and the one which Davies seems to favor, is that we are looking for the wrong thing. We assume that ET will send a straightforward radio signal of a type we can easily detect and understand. This book claims to question our assumptions about SETI, throw out the unjustified ones, then on a more solid grounding, renew our efforts at listening and searching.
Unfortunately, despite much lip service against “anthropocentricism,” the author seems reluctant to squarely address the self-serving assumptions that SETI researchers, himself included, still make, such as that ET would be using radio technology, broadcasting at the spectral frequency of hydrogen.
Instead of dealing with such arbitrary assumptions, Davies spends chapters discussing whether a second “tree of life” could have arisen on Earth, which would prove that life has originated more than once. That would greatly increase our confidence in the search for ET. But he does not consider whether “the tree of life” is a uniquely human construct, and he unthinkingly assumes the universality of Darwinian evolution, because, apparently, that is a sacred cow.
In an equally frustrating section, Davies evaluates the terms of the famous Drake Equation, a set parameters whose combined probabilities give the likelihood of finding intelligent life in the stars. Unfortunately, and inexplicably, neither of the critical parameters, “life” or “intelligence” is defined, rendering the whole exercise meaningless.
Glossing right over that deal-breaker, Davies goes on to speculate without inhibition about different strategies for detecting ET, from searching for beacons rather than messages in the radio spectrum, to looking in undersea hydrothermal vents instead of the stars, to scouring the solar system and the planet for mini-robots, in case “they” have already arrived.
Despite my frustration, I was still hopeful to learn about the Post-detection Taskgroup, which Davies chairs, because a serious question concerns how people would react if ET were positively detected. Would it be a replay of “War of the Worlds?”
The answer is what amounts to a calling list. First, the SETI researchers would notify the International Astronomical Union, then the UN, other governments, and end with a press conference. If that is the most imagination a SETI task force can muster, I despair.
This book is helpful on the short history of the SETI enterprise. There isn’t much science, and what’s there is swamped by speculation. As psi-fi, the text fails utterly, as Davies, like most scientists, is blind to his own subjectivity.
The popular question, “Are we alone?” which seems to haunt even SETI scientists, is not such a mystery. I can answer it right now. No, we are not.
Three hundred thousand species of beetles roam the earth, and we have communicated with not one of them. Beetles are alive and intelligent enough to be survivors in their niches. Until we figure out how to understand beetles, we might as well give the SETI telescopes a rest.
Davies, Paul (2010). The Eerie Silence: Renewing our Search for Alien Intelligence. New York: Houghton Mifflin Harcourt, 241 pp., indexed.