A new scientific paper published by a researcher with a Ph.D in computational neuroscience, a nanotechnology researcher, and a moral philosopher theorizes that there is a “substantial probability” that outside of Planet Earth, there is no other intelligent life in the observable universe.

World Series of Poker champion and physicist Liv Boeree enthused:

The abstract for the paper states that the conflict between the apparently lifeless universe that we observe and the Drake equation, which suggests the sheer multitude of possible sites for intelligent life should yield a large number of potentially observable civilizations, arises from the use of Drake-like equations, which are not necessarily reliable. The paper notes, “But while the equation is often invoked as a way of reasoning about uncertainties and ignorance, the actual practice is often considered to be somewhat suspect. Many papers state that some of their parameter choices are just their best guesses, though this fails to provide an appropriate framework for interpreting the result.”

The abstract notes that “extant scientific knowledge corresponds to uncertainties that span multiple orders of magnitude … When the model is recast to represent realistic distributions of uncertainty, we find a substantial probability of there being no other intelligent life in our observable universe, and thus that there should be little surprise when we fail to detect any signs of it.”

The authors conclude:

When we take account of realistic uncertainty, replacing point estimates by probability distributions that reflect current scientific understanding, we find no reason to be highly confident that the galaxy (or observable universe) contains other civilizations, and thus no longer find our observations in conflict with our prior probabilities. We found qualitatively similar results through two different methods: using the authors’ assessments of current scientific knowledge bearing on key parameters, and using the divergent estimates of these parameters in the astrobiology literature as a proxy for current scientific uncertainty.

When we update this prior in light of the Fermi observation, we find a substantial probability that we are alone in our galaxy, and perhaps even in our observable universe (53%–99.6% and 39%–85% respectively).