Several years ago the Ontario chapter of Canada’s Centre for Inquiry and the University of Toronto Secular Alliance hosted “The Great Extraterrestrial Debate” between SETI senior astronomer Seth Shostak, astrophysics professor Ray Jayawardhana, and award-winning Canadian science fiction author Robert J. Sawyer. Bob McDonald, the host of CBC’s Quirks & Quarks, moderated the event at the Macleod Auditorium in the University of Toronto’s Medical Sciences building.
The Centre for Inquiry, which promotes “reason, science, secularism, and freedom of inquiry,” held this debate in the spirit of the motto “extraordinary claims require extraordinary evidence”.
According to this motto, the existence of ET is an extraordinary claim, and all three presenters agreed that to date, in spite of decades of search and research, there is not a shred of peer-reviewed, scientifically accepted evidence that ET exists.
Why we haven’t yet found extraterrestrial life
All three presenters conceded that the sheer size of the universe makes it highly unlikely that we would be the only intelligent life in it.
Ray Jayawardhana pointed out that there were more galaxies in the universe than there are grains of sand on all the beaches and in all the deserts in the world and invited audience members to lie down on a beach somewhere and hold a grain of sand on the tip of a finger, and know that in cosmic terms we, the Earth, are smaller than a microbe on that one little grain.
What are the odds that no other intelligent civilization exists in all the vastness beyond us?
The problem with finding ET is not ET’s non-existence but our limited means of searching for him. In terms of the age of the universe, our technological civilization has been in existence for a little more than an instant.
While the universe is 13.5 billion years old, Marconi invented the radio a mere 126 years ago. SETI, the program to find extraterrestrial intelligence, has been sending out radio waves to a small segment of the sky for only half a century.
Seth Shostak, senior astronomer at SETI, pointed out that to conclude, based on the evidence to date, that there is no intelligent life out there would be the same as concluding after confining one’s search to a single square block that there are no elephants in Africa.
Another part of the difficulty in finding ET is our limited definition of what ET might look like. If we assume that ET is like us (to quote Robert J. Sawyer, “bipedal, carbon-based, eats food, excretes, does respiration”), we are limited to looking for planets that support such life.
But the program that searches for earth-like planets in which Ray Jayawhardana is involved has found a much vaster variety of worlds than we ever imagined, including a planet the size of Jupiter that whizzes around its sun in four days. Life could take on many forms that are not carbon-based, or bi-pedal, or oxygen and water dependent.
Robert J. Sawyer pointed out that we don’t even know what an adequate definition of life is and that we only assume that we will recognize it when we see it. Life on Earth for most of its existence did not take a human form.
In fact, all the presenters agreed that there might be a greater chance of extraterrestrial life looking like pond-scum than anything like us, and that intelligence is not a pre-requisite for life existing on a planet. It is only our human arrogance that makes us presume that life everywhere tends towards intelligence as its highest expression.
How do we communicate with ET?
Even if we recognize life on other planets, how will we communicate with it? The presenters quipped that as we know from Star Trek, all extraterrestrials speak idiomatic English and are members of the Hollywood actors’ guild. But joking aside, there could be a multitude of means of communication not involving radio waves.
Seth Shostak pointed out that it took us 50 years from the discovery of radio to the discovery of computers, and that in 200 years computers would far outstrip the human brain in capacity and this will raise the possibility of a machine-based, rather than carbon-based, civilization.
Civilizations hundreds of thousand of years more advanced than ours may have already reached that point, and, as Robert J. Sawyer commented, may have long ago adopted more advanced means of communication, as for instance quantum entanglement.
Not a single radio wave would emanate from such a civilization for us to discover. An audience member added the observation that we have not even been able to establish communication with other advanced species on our own planet, such as whales and dolphins.
The future of the search for ET
Both Seth Shostak and Ray Jayawardhana were optimistic about our chances of finding ET in “the next couple of decades”, in fact they were each willing to bet a cup of coffee on it.
Dr. Jayawardhana pointed out that our ability to discover earth-like planets has increased many-fold in the last fifteen years due to the deployment of the Kepler telescope, and will increase further.
He advocates finding and looking at thousands of planets, plotting them, and identifying which ones stand out, and not limiting ourselves to focusing on requirements like water and oxygen.
Both Dr. Shostak and Dr. Jayawardhana believe that we should increase the scope of the material we send out, because greater diversity increases the possibility that someone would be able to interpret at least some of it.
Dr. Shostak even suggested that we should send up the internet as being representative of the intelligence of our species, which led to some joking about internet porn, which Robert J. Sawyer felt would not present a problem because it would be “species specific” and not likely to make much sense to aliens.
Are we ready for contact?
The presenters touched on Stephen Hawking’s concern that we are revealing too much of ourselves already and perhaps making ourselves a target and dismissed it.
Dr. Shostak thought that the biggest danger we faced from an alien civilization was “too much knowledge” that we were not ready to comprehend and use to our benefit.
So for instance if aliens were to teach us the technology to create cheap, unlimited energy in our garages from dark matter, an Osama Bin Laden might just use it for havoc and destruction.
The possibility exists that other, more advanced civilizations already know about us, but are waiting for us to resolve our planetary problems before initiating communication.
Dr. Shostak said that the discovery of ET might hardly cause a blip in our social consciousness, given that one-third to one-half us believe that the extra-terrestrials are already among us.
Our reaction would be dependent on the nature of the discovery (i.e, bi-pedal life-forms that waved and smiled at us would enerate more popular excitement than alien pond-scum, even if it is intelligent). Radio host Bob McDonald thought that the media would only be interested if ET came waving guns or wanting to eat us.
Not wanting to indulge in disaster scenarios, Robert J. Sawyer commented that it is human conceit to imagine that we would be interesting to them. Seth Shostak added that while we have achieved much with our 3-pound brain, it does have its limitations, particularly when it comes to dealing with advanced civilizations that have been around hundreds of thousands of years.
But Ray Jayawhardana optimistically thought that in the search for ET we would only be limited by our imagination (and of course lack of funding).