We are not alone

The Drake equation was developed by Frank Drake in 1961 to estimate the number of communicating civilizations in our galaxy. That's right - ET's. Drake thought that once an alien civilization learns to communicate in ways we can detect across space they would continue to do so over an average of 10,000 years until they went the way of ancient Rome. Using this number he estimated there were currently 10,000 communicating civilizations in our galaxy. 10,000 civilizations amongst 200 billion stars in our galaxy - the proverbial needle in the haystack. It could take a very ,very long time before we detect anything, if ever.

But Drake may have grossly underestimated. Technological growth is not linear - as it intuitively appears to be, and as Drake thought of it - it is exponential. Once civilizations reach the capability to communicate using electromagnetic radiation - light, radio, television, etc - ways we recognize today - their technological growth would be about to experience massive expansion. Shortly after radio would come computers. Shortly after that artificial intelligence. Shortly after that - massive growth of intelligence and capability. We ourselves are on the verge of this massive expansion. We will experience intelligence millions, if not billions of times our current level within the next 100 years. We wouldn't be able to recognize our future selves or detect the ways we will communicate using today's technologies. From the onset of radio to unrecognizable communication in less than 200 years.

Civilizations then more likely communicate in a way we can recognize today not over 10,000 years but more like 100-200 years. The solution to the Drake equation would then be 100-200 civilizations not the 10,000 he solved for. 200 alien civilizations in a 200 billion star galaxy would make for a very lonely universe indeed.

But does this mean there really are only 200 advanced civilizations in all of the galaxy? We started this line of reasoning saying Drake grossly underestimated. Again, if we consider the exponential growth of intelligence and technology things change dramatically. Drake believed that intelligent life could only evolve on planets. Part of his equation then depends on an estimate of the number of life sustaining planets in the galaxy. But exponential technological and intellectual growth would guarantee massive expansion of intelligent life beyond planets. Consider this and his equation then solves in the millions - perhaps billions.

Billions? We've been looking for intelligent signals from space for fifty years and found nothing. But we've been looking for civilizations close to our own level of intellectual and technological development - the 200 in 200 billion after all. The silence we are experiencing in our search for alien intelligence then more likely a reflection of our crude intellectual and technological beginnings than an indication of lack of intelligent life in our universe. Devise ways of communicating with a billion fold greater intelligence - and the sky should light up.
www.pbs.org/wgbh/nova/origins/drak-flash.html