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Entries in "Extra Terrestrial Intelligence"
January 31, 2008
Extra Terrestrial Intelligence-4: What if we get a signal?
One of the big problems with ETIs is that it is very unlikely that we can make actual physical contact with them. One reason is just statistics, as I said earlier. While the odds of life existing elsewhere in the universe need not be too small, the chances that any one ETI will cross signals or even paths with another is very small, due just to the immense size of the universe compared to the speed of our travel and communications.
But there is another problem working against an actual meeting between an alien life form and ours. Although we believe that the laws of physics and chemistry are universal in their application, the laws of biology are not believed to be so. All the life forms on the Earth have evolved in its peculiar mix of oxygen-nitrogen atmosphere, along with its abundance of water. Life on other planets would have evolved in completely different environments and are unlikely to resemble the forms we are familiar with except for the broad constraints laid down by the laws of physics and chemistry. It would be an absolutely stunning discovery if the life forms we encounter were also oxygen-breathing, water-drinking, cell-phone using beings like us. That would imply that the range of conditions under which life can occur is far more restrictive, and the laws of biology far more universal, than we had anticipated. It would also mean that the probability of life originating on other planets is even lower, since they would require environments similar to ours in many ways.
Even universal laws like gravity can cause problems. If an organism has evolved on a planet that has a gravity field much different from ours, that could pose problems for an actual meeting. Organisms that have evolved to survive in a field of a certain size would find it hard to move and maneuver in fields that are much greater.
In any event, even if the time-space-technology barriers are somehow overcome and an actual direct encounter takes place, any face-to-face encounter between an ETI and us will likely have to take place with either or both being encased in spacesuits that can simulate the required environment.
For an atheist, the discovery that ETIs exist, like any other scientific discovery, brings with it only wonder and curiosity. There is no dogma to be disturbed. But for religious people, questions about life and origins are inextricably bound up with religious doctrines and are bound to cause problems. Most religions, although making claims of universality, are really quite parochial, basing their entire theology on claims of what has happened here. There will have to be some scrambling to try and incorporate the new facts of the existence of other intelligences into an Earth-based theology.
Nowadays we tend to forget the fact that it was much easier during the pre-Copernican times to believe in a personal god with whom one was in direct contact. A finite and fairly small universe with the star-embedded heavens not too far away made it easy to think of god as a human-like entity keeping an eye on us from heaven. All such a god would need were heightened human powers, like extremely good eyesight to be able to see everything and some form of ESP to read our minds. Since the distance from heaven to Earth was not that great, it was possible for god to act quickly and easily everywhere.
The realization that the universe was vast and possibly infinite raised issues that were far trickier, and this has been dealt with by emphasizing more the notion that 'god is everywhere.' While this solves the problem of how god can know everything instantaneously, it also makes it harder to visualize a human-like personal god. The advance of science and the notion that everything must obey the laws of science has caused other problems for the idea of a personal, human-like god. For example, the restriction that no information can travel faster than the speed of light means that a god who is everywhere and knows everything 'at the same time' must be violating this law somehow, even if one overcomes the problem that simultaneity is no longer a universal quality under the laws of relativity. So we now have the conundrum of a god who violates his own laws. This is why religion needs to indoctrinate children into religious beliefs at an early age and surround them with communities where such questions are not raised, and where meaningless platitudes such as 'god is everywhere' are accepted as deep truths, beyond the reach of reason and logic.
It seems to me that if life were to be discovered on distant planets, and not just any old life but a society with vastly superior capabilities, surely the man-made nature of religion and god would be obvious to everyone?
But that may be just my prejudice. I suspect that the discovery of ETIs would cause theologians to put in overtime to come up with some rationale as to why this is consistent with whatever their respective religious texts say. Organized religion is too much of a profitable business for its beneficiaries to allow their cash cow to go under due to the emergence of inconvenient facts. They will dust off the writings of some previously obscure religious mystic whose words could be construed to mean that he had anticipated this discovery, and the mystic's words would be used to show how the religious texts are correct and even prophetic and scientific. Thus the discovery of ETIs will be portrayed as a triumph for religion. This is similar to the way that St. Augustine's words are now interpreted by some to suggest that he had anticipated the big-bang model of the universe.
I actually do hope that we receive a signal from outer space. To my mind, it will confirm what I have long held: that all the differences that we dwell on here such as ethnicity, religion, geography, nationality, are just tiny and superficial and largely artificial, not worth fighting and killing over. Furthermore, it should give us hope that societies can deal effectively with advanced technology and need not end up destroying themselves with it, either by blowing themselves up or by slowly strangling their own planet, the way we are currently risking things.
But while that is my hope, that may not happen. It is possible that while there may be a spurt of such forward thinking in the immediate aftermath of receipt of a signal, eventually that knowledge will become part of our background knowledge. When people realize that there is going to be no practical consequence to this discovery and that we will not be able to actually meet the aliens, they will go back to their usual ways, listening to their preachers explaining how all this fits in with god's mysterious plan, and why their own group of people is still very special in god's eyes, so special that killing people who are different is a virtuous act.
The only benefit we may get from receiving ETI signals might be if we could decipher the signals to get information that might provide some insights into new scientific and technological breakthroughs that might help us deal with some problems on Earth, such as global warming or the rapid depletion of energy and other natural resources.
That is not as exciting as being able to meet and chat with other intelligences, but it is not an insignificant benefit.
British comedians John Bird and John Fortune explain how everything is going according to George Bush's grand plan.
January 30, 2008
Extra Terrestrial Intelligence-3: The most likely contact scenario
What is likely to be our reaction if we did receive an unambiguous signal that there existed ETI somewhere else in the universe?
The reaction would be hard to predict because it is not a topic that is not publicly discussed much. This is a bit surprising because it is not such a stretch to think that we could wake up one morning to find out that we have received some signal from an alien civilization. I suspect that the reason why we don't speculate on this question is that any such occurrence might be extremely difficult for most people to absorb into their existing worldviews, so they avoid thinking about it.
Take religious believers. If there is life elsewhere, what does that do to the common idea that humans somehow have a special relationship to god? For Christians, if Jesus died on Earth as a redemptive act for all humankind, did a similar event take place with these other alien civilizations? Would Jews still be able to see themselves as some god's chosen people? Why did the angel Gabriel not reveal this information of ETI to Mohammed during one of their chats?
I suspect that religious apologists would quickly get to work to come up with new doctrines that would keep the faithful loyal. After all, very similar theological challenges have been encountered before although they are not remembered now. After Copernicus's ideas about a heliocentric solar system sank in and it became clear that the Earth was merely one of several planets, theologians worried that this meant that other planets could also have inhabitants and this would cause problems for religious doctrines.
As Thomas Kuhn pointed out in book The Copernican Revolution:
When it was taken seriously, Copernicus' proposal raised many gigantic problems for the believing Christian. If, for example, the earth were merely one of six planets, how were the stories of the Fall and of the Salvation, with their immense bearing on Christian life, to be preserved? If there were other bodies essentially like the earth, God's goodness would surely necessitate that they, too, be inhabited. But if there were men on other planets, how could they be descendents of Adam and Eve, and how could they have inherited the original sin, which explains man's otherwise incomprehensible travail on an earth made for him by a good and omnipotent deity? Again, how could men on other planets know of the Savior who opened to them the possibility of eternal life? … Worst of all, if the universe is infinite, as many of the later Copernicans thought, where can God's Throne be located? In an infinite universe, how is man to find God or God man? (p. 193)
The Copernican model, once its implications were fully appreciated by the theologians, thus raised some serious problems. Fortunately for the theologians, no life was found on the other planets so they did not have to deal with the implications of original sin, of Adam and Eve as being created in god's image, of the fall from grace, of Jesus as savior, and so on.
Similar problems were encountered with the early exploration of the world. Before the arrival of Europeans in the New World, for example, St. Augustine went so far as to argue that there could not be human beings already there because the Bible said that all humans were descended from Adam and Eve, and since there was no way that their descendants could have got to the other side of the Earth (what they called the Antipodes), that meant there could not be any humans there. Such was the typical approach of one of the Catholic Church's great thinkers: start with a doctrinal belief and then use that to predict what the data should reveal. In science, we may start with a paradigmatic model to make a prediction but we never depend upon any revelation or a special text.
Of course, Augustine was wrong. But as always, the theologians managed to absorb the discovery that the New World was indeed inhabited and devise ways to incorporate these new and awkward scientific facts in ways to keep the faithful loyal.
Next: The potential benefit of receiving signals an ETI.
POST SCRIPT: But seriously,…
Our wise pundits start to discuss the really important issues.
January 29, 2008
Extra Terrestrial Intelligence-2: The chances of ETI existing
I thought of ETIs because of recent sudden reports of their appearance. About 40 residents of the town of Stephenville in Texas reported seeing a UFO a few weeks ago. And then the website Machines Like Us highlighted the reception of a mystery signal by a radio telescope in Puerto Rico. Nothing definitive has been said about the source of either signal, leaving the field ripe for speculation by ETI believers.
Now I think it is likely that there is life somewhere out there in the universe. The huge number of stars in the universe seem to imply that as long as the probability of life emerging spontaneously is not zero (and we know this is true since we are here), then we should not be surprised at it occurring in other places, perhaps in many places. The catch is that given the size of the universe, the probability of any one of these forms of life encountering another is very small. The most likely way that we will detect their presence is by accident, if they happen to send out a signal strong enough in all directions so that is it detectable by us even at these huge distances. Even then, although we would know the direction from which the signals came, it would be hard to know how far away they are. The premise of Contact was that a planet fairly close to us (near the star Vega just 25.3 light years away) containing ETI had received our old TV signals, thus discovering our existence, and then decided to reach out to us.
But although I think that it is likely that ETIs exist, what I am really skeptical about are the usual reports of UFOs and other sightings, where alien spacecraft dart hither and thither at high speed, playing peek-a-boo with us. If intelligent life evolved near other stars long enough ago that they could travel the likely millions of years necessary to get to Earth, they must be possessed of a vastly superior science and technology than us simply in order to even find us.
After going to all that trouble, why would they then start playing the fool, scaring the daylights out of rural Americans? And why is it that it seems like it is mostly rural Americans who get these visits? Why don't they drop in on Central Park in New York City?
While it seems likely that the present kinds of UFO sightings are nothing more than misidentifications, the idea that we could receive a signal from ETIs is intriguing and worth mulling over. The most likely thing to happen is that we do get some sort of identifiable, non-noise, intelligently created electromagnetic signal from outer space, broadcast by the inhabitants of some distant planet without any specific intention of contacting anyone, just the way our own radio signals have been beamed out to the universe for the last 100 years or so and TV signals for about 70 years. Electromagnetic waves have some huge advantages as communication devices: they can carry detailed information, can travel through the vacuum of empty space, and travel at the fastest possible speed allowed by the laws of science, which is the speed of light. But that very fact shows how limited our reach is, since it would take about 100,000 years for these waves to just cross our own Milky Way galaxy.
Even if we did get such an unambiguous signal about the existence of an ETI from some source and could decipher it, there is little that we could do with it, just the way that a distant civilization would be baffled if, millions of years from now, they were to pick up the weak signal from a broadcast of American Idol. We would not be able to communicate back and the long times involved in sending and receiving messages would sap the enthusiasm of the most ardent believer in ETI. In science fiction, this limitation is overcome by invoking speculative scientific exotica like black holes and worm holes that enable space travelers to circumvent the speed-of-light limitation and somehow 'tunnel' to distant locations in very short times. But while that meets the plot needs of authors, there is no hard evidence that such things exist or, if they do, could be used for such kinds of travel.
But if we leave all these kinds of exotica aside, what intrigues me is what would happen if we simply experience the absolute minimum, which is the receipt of some signal that unambiguously indicates that somewhere out there, however far away and unreachable, there exists intelligent life. Would that change anything here? Would it influence the way we think and behave amongst ourselves, even if there was no possibility of actually communicating with that intelligent life? Or would the novelty soon wear off, and we go back to our usual practice of killing each other?
Next: How should we react to receiving a signal?
POST SCRIPT: Wisdom beyond any price
What would be do without our profoundly wise national commentariat?
January 28, 2008
Extra Terrestrial Intelligence-1: Getting a signal
In the years 2002 and 2003, during the peak of the intelligent design creationism (IDC) movement, I was invited to a few meetings of that movement to provide the opposing view. This was the time when the IDC side was promoting such debates as a means of increasing visibility for IDC ideas.
During those meetings I heard over and over again about the significance of the film Contact, based on the novel of the same name by astronomer Carl Sagan. This surprised me because I knew Sagan was a self-described agnostic. Why was the work of such a well-known skeptic being shown so much love at gatherings of religious believers? I was intrigued by this question but didn't get around to reading the book or seeing the film until I did both last month.
I now understand the IDC people's fascination with Contact. The book and film deal with extra-terrestrials making contact with people on Earth. The signal of their existence is that radio telescopes on Earth start receiving a series of pulsed signals from outer space that are the sequence of prime numbers, which are numbers that can only be divided by themselves or one. (i.e., the numbers, 1,2,3,5,7,11,13,17,19,23,…)
While prime numbers are a source of great fascination for mathematicians and are used by them in a wide variety of ways (cryptography being one), there is no naturally occurring physical process that generates those numbers. Hence the reception of prime numbers is an unambiguous signal of a real intelligence out there manufacturing these artifacts, unlike the earlier false alarms created by the detection of pulsars in 1967. Those earlier signals consisted of regular pulses of energy with very precise times between each pulse and initially were thought to be signals sent by an extra-terrestrial intelligence (ETI) but were later found to be caused by rotating neutron stars. But one would be hard pressed to find naturally occurring physical explanations for signals that had the pattern of the prime numbers
The IDC people used this idea from Contact to argue that the existence of certain biological systems could not occur naturally and hence were similarly unambiguous signals for the existence of an 'outside' intelligence. While this intelligence could also be extra-terrestrial (as postulated by the Raelians), the IDC people preferred to believe that it was caused by god. This was the Paley's Watch and Mount Rushmore metaphors modernized.
I found both book and film interesting but mildly dissatisfying. Sagan's weaknesses as a novelist show, though his knowledge and command of science help to make the book readable.
All books and films that deal with contact with ETIs suffer from the same problem, that the really exciting part is the thrill of discovering the existence of extra-terrestrial intelligence and the anticipation of what aliens look like, are like, and their attitudes towards us. But we just do not have any data at all on which to base our conceptions of these alien beings, so any choice the authors make is bound to be seen as deficient. Whatever the creators dream up about the actual encounter cannot help but be a bit of an anticlimax.
All the novels that I have read on this topic (admittedly not that many) suffer from the fact that the plot's dynamic requires a revelation of the ETI at the end but the actual realization of the concept is almost always disappointing. I don't see any way around it.
Next: More on ETIs.
POST SCRIPT: How to become a New York Times columnist
All you have to do is be consistently wrong.