Everyone has seen the famous Drake Equation on those educational astronomy shows—the equation that multiplies the nearly infinitely large number stars in the universe by several seemingly miniscule fractions—expressing the number of civilizations in the universe that have progressed to the point of radio communication. Despite this, it still always manages to produce some preposterously large number of intelligences from whom we should have already heard. So why isn’t the sky saturated with these radio signals from extraterrestrials?
Two hundred years ago, we had no interest in listening for other forms of life on the edge of our galaxy. The scientific knowledge of the time was not developed enough to allow us to be curious about extraterrestrials and radio transmissions from space. Now, our civilization is at the height of its curiosity. On the edge of comprehending quantum mechanics but still searching for a "theory of everything", we understand just enough science to pique our interest—to make us hungry for more. We can see the amazing things—things like nanotechnology—that are possible but just out of our reach. Will this curiosity dwindle as more of this becomes possible—and real?
In our Age of Curiosity, we know computers can simulate our environment and predict what will happen given certain initial conditions. The universe operates under specific physical laws and—given starting conditions, such as the conditions of an early earth on which life arose, a computer could theoretically track the position of every atom as amino acids formed, the first cells divided, and the first creature came out of the water. What stops us from doing this now? Time. Our current level of computational speed is too primitive to handle but the simplest of prediction-type tasks, such as deciding how wind will interact with an airplane or how heat will warp a metal container. Even these are too complex to be calculated on the atomic level; we must use equations that describe the motion and flow of gasses and liquids on a large scale to run such simulations.
Will we still be as interested in contacting other life when computers are fast enough to simulate a million years of evolution in a few days? Who would want to wait a thousand years to get one response from a distant and potentially hostile civilization when we can converse in real time with our own computer-generated population simulated in a consumer-level computer? The only question is of when computer technology will reach this speed. Obviously, such computational speed is far beyond any amount of copper wire and almost any number of cubic miles of nanotechnology. It is not beyond quantum computing, if such a thing is possible on a large scale. How long will this advance take? Ten years? A hundred years? Two hundred years at the absolute most?
What if such a level of quantum computing proves to be impossible? Even if we cannot completely simulate large environments and watch evolution progress on the atomic level, we will have soon unraveled the mysteries of life. The Human Genome Project is nearly complete. Not too many years afterwards, we will know the purpose of every nucleotide of the human genome. Creating entire organisms from nothing but a graphical interface and gene-sequencing machine (which already exists) is no more than a hundred years away. Whether specific advances are possible or not is irrelevant. What is relevant is the eventual decline in curiosity about alien civilizations and contact as ability and technology increase. The above two advances are just examples.
When did our civilization have the greatest capability for destruction? Our curiosity about other intelligences and making contact piqued in about the same period as our ability to make atomic weapons. For all civilizations, the discovery of the destructive power of subatomic energy likely follows the discovery of radio communication; the scientific understanding required for both is closely related. Who would want to communicate with a potentially violent race in the prime of their destructive ability and the maximum of their naivety to use this destructive power?
Why is it when we think of other intelligences, we always imagine they are peaceful? We certainly are not. It is time-tested knowledge that when a stronger population encounters a weaker population, the weaker population is enslaved or killed. When human society reached industrialization, the environment and lesser species paid the price. Over one hundred species a day are becoming extinct because of our actions. When the Europeans came to North America, they killed the Native Americans and enslaved the Africans. Why do we believe this would not hold true for interplanetary relations? Is it wishful thinking, since we will likely be the lesser race? Can you imagine us visiting a planet with Neanderthal-level inhabitants and not vastly exploiting them and their planet, even if just for natural resources? Other civilizations would likely have experienced similar problems in their past; it’s not much of an incentive to broadcast your presence.
How long will we even use the current methods of radio communication? We are a long way away from the slow, analog streams sent out fifty years ago. As communications are increasingly becoming more broadband, spread-spectrum, digitally encrypted, and compressed, our likelihood of being noticed decreases. Eventually the earth will be nothing more than a tiny, barely noticeable spec in the background radiation of the universe. Other civilizations would also make the transition from nominally modulated analog communications to spread-spectrum compressed digital. Perhaps some of this background noise isn’t noise at all.
One hundred, or for the sake of argument, five hundred years of nominal curiosity about other civilizations is an extremely small slice of the eight billion years or so the universe has been hospitable for the creation and proliferation of life. If every civilization only concerned itself with making contact for a millionth of their evolutionary development, what are the chances of one civilization hearing another other at exactly the right time? Rather than imagining solid spheres of radio transmissions emanating from innumerable sources—an image that makes us wonder why earth is not saturated with signals, picture thin shells at different radii from those sources. How often will one of these shells intersect a planet that is currently in its Age of Curiosity? That is, how often will a civilization in its Age of Curiosity receive a signal from a civilization sent during its Age of Curiosity? If by some remote chance one planet received radio communication from another civilization and attempted a reply, the broadcaster would have likely already lost interest and stopped listening.
It is time to update the Drake Equation to include another miniscule fraction—the ratio of a civilization’s Age of Curiosity to its lifetime. Will this addition keep the number of communicable civilizations optimistic enough for us earthlings, in our Age of Curiosity?