Is Entropy the Key to Finding Alien Civilizations?
When attempting to find alien civilizations, the employed methods can be viewed as too human-centric, or coming from a place that anthropomorphizes the unknown aliens without any proof that they're anything like us. For example, some astrobiologists have been searching for radio waves in order to find technologically advanced civilizations, but there's no guarantee that other civilizations would use radio waves, as there is no reason to believe that they would follow a similar trajectory as us. But a new study from the University of Rochester proposes a virtually universal solution for finding extraterrestrial intelligence: entropy.
Entropy is essentially a measure of a system's disorder; according to the second law of thermodynamics, physical work cannot be done without the transfer of heat from a warmer body from a cooler one, and an increase in heat also increases entropy. Therefore, harvesting energy in order to do work, which is essentially the basis of our usage of technology, involves increasing the entropy of our environment. In their paper, astrophysicists Adam Frank and Woodruff Sullivan assert that producing entropy is a defining feature of a technologically advanced civilization, and as a result is the key to finding ones other than our own.
"If they use energy to produce work, they're generating entropy. There's no way around that, whether their human-looking Star Trek creatures with antenna on their foreheads, or they're nothing more than single-cell organisms with collective mega-intelligence. And that entropy will almost certainly have strong feedback effects on their planet's habitability, as we are already beginning to see here on Earth."
The study also focuses on this research's applicability to studying whether humans' trajectory is part of a universal pattern, the analysis of which could yield projections about our sustainability and overall future (It fittingly appears in the journal Anthropocene, which refers to the proposed name for the current epoch as defined by the human toll on the environment.) "We have no idea how long a technological civilization like our own can last," said Frank. "Is it 200 years, 500 years or 50,000 years? Answering this question is at the root of all our concerns about the sustainability of human society."
From the paper: "The point is to see that our current situation may, in some sense, be natural or at least a natural and generic consequence of certain evolutionary pathways."
The authors contend that we should learn from other species' successes and failures in order to make decisions, about our interaction with the environment in particular, in order to avoid extinction. "Maybe everybody runs into this bottleneck," says Frank. "If that's true, the question becomes whether we can learn anything by modeling the range of evolutionary pathways. Some paths will lead to collapse and others will lead to sustainability. Can we, perhaps, gain some insight into which decisions lead to which kind of path?"