Astronomers are now looking for signs of life in the “habitable zones” of nearby stars, defined as the band around a star where liquid water could potentially exist. But a recent article argues that we should take a more nuanced and cautious approach based on the potential of computing, not the potential of life.

One way of describing life itself is a series of calculations operating on information. Information is stored in DNA and calculations are done by various proteins. The ability to store information and influence the environment allows life to be subjected to natural selection, which finds increasingly complex mechanisms.

Traditional pursuits of life look at how we understand it from a worldly context. That is, creatures that live on the surface of an earth at the right distance from their parent star and use liquid water as a solvent for chemical reactions. But it is easy to imagine much more complex and diverse life forms in the universe.

Life can use other solvents. Life may be buried underground during the icy outer months. Life may not even need a star. And biological systems can give rise to technological systems that don’t fit our current definition of life, but could be alive in their own way.

And so a few researchers want to reframe the concept of habitat using a more fundamental concept of computing. They argue that the best chance of finding vital signs is where there is easiest access to the computer. These so-called computational regions require three properties, the researchers say.

First, there must be computational ability which means a rich set of chemistry is available. Second, it must be a raw form of energy, such as sunlight or hydrothermal vents. And finally, computation requires a substrate where computation can take place.

The traditional view of residential districts can now be seen as a subset of the much broader concept of computing districts. Where there is life, as we understand it here on Earth now, calculation takes place. But this framework allows us to develop strategies for finding life concepts that go beyond that.

For example, if we examine individual systems through the lens of computational capabilities, we can discover which systems might be suitable for artificial energy harvesting structures such as Dyson spheres. Or we can discover how gas clouds around substellar structures can meet all the conditions necessary for computation and therefore for an expanded description of life. The scientific search for life in our universe has just begun. As the authors emphasize, it’s important to keep an open mind.