The Fermi Paradox is a name given to a problem first proposed by the Italian physicist Enrico Fermi over lunch one day. Fermi had observed that any basic assessment of the number of stars and assumed planets with chemistry and organisms for life, and their associated timescales, suggested that if intelligent extra-terrestrials did exist in the galaxy, then statistically they are either here now or have been here in the past.
The Drake equation is a name given to a formula expression of multiplicative terms, to describe the probability of life evolving on another planetary biosphere independently. It is named after the American astronomer Frank Drake. The terms include things like the rate of star creation in the galaxy, the average number of planets around stars that might support life, the fraction of those planets that develop life, the fraction that develop intelligent life and the lifetime of any such civilisations that may develop communications technology to eventually transmit into deep space. However, the final term, designated ‘L’ makes a rather grand claim that is worth exploring a little further.
Project Cyclops
A key study that underpinned this equation was Project Cyclops in 1971, written by B M Oliver, J Billingham and others with the title ‘Project Cyclops, A Design Study of a System for Detecting Extraterrestrial Intelligent Life”, (NASA-CR-114445). Some of the conclusions of this seminal work included “It is vastly less expensive to look for and to send signals than to attempt contact by spaceship or by probes”, and “The cost of a system capable of making an effective search, using the techniques we have considered, is on the order of 6 to 10 billion dollars, and this sum would be spent over a period of 10 to 15 years”, and “The search will almost certainly take years, perhaps decades and possibly centuries”. When reading this report, and other papers that came later, it did seem to converge on a conclusion by the SETI community that starship travel was not likely possible and this does indeed seem to be the view of Frank Drake.
It is interesting that the term in the Drake equation ‘L’ does seem to imply that any advanced extraterrestrial civilisation would only attempt to reach out to other civilisations in the Cosmos by transmitting radio (or optical) beacons. No consideration is given to the idea that instead they may choose to build a starship and travel across that distance and interact on a physical level. This brings up an interesting examination on the consistency of the thinking of both Drake and Fermi and it would appear there are two interpretations possible.
Interpretation (1); Fermi’s observation that they should be here (or have been here) yet we don’t see any, is suggestive of the conclusion that any advanced ET would make contact by long-distance transmissions, and so therefore is completely consistent with the Drake equation.
Interpretation (2); Fermi’s observations that they should be here appears to be predicated on the idea that interstellar travel must be possible, and so on this basis it is not consistent with the Drake equation and in fact is in competition with it. This is because it implies that there is a further term that needs to be added to the Drake equation that takes account of interstellar diffusion by starships.
Well, it is up to each individual to come to their own conclusion. But it is worth noting that the physics basis for interstellar travel was first demonstrated theoretically by L Shepherd in a Journal of the British Interplanetary Society publication titled ‘Interstellar Flight’ (JBIS, 11, pp.149-167, 1952). Then in the 1970s the Project Daedalus team, went on to design over five years an actual starship concept that was credible in principle, as a proof of existence theorem. Their conclusion was that if they could conceive of such a machine at the outset of the space age, then in the future centuries it is likely that we could do much better and so interstellar travel was possible. Alan Bond and Anthony Martin, members of the same Daedalus team also went on to design full world ships in the 1980s, with papers titled “World Ships - Concept, Cause, Cost, Construction and Colonisation” (JBIS, 37, pp.243-253, June 1984) and “World Ships - An Assessment of the Engineering Feasibility” (JBIS, 37, pp.254-266, June 1984). This work demonstrated that not only was reconnaissance by interstellar probes likely possible, but so too was colonisation.
Many other studies have also been conducted to support this conclusion and it is curious that many in the SETI community seem to hold onto the ‘starships are impossible’ mantra, almost as a form of dogma. Only time will tell who was right.
Daedalus Starship (Don Dixon)