Presentation #220.02 in the session SETI, Technosignatures, and the Search for Life.
The stellivore hypothesis proposes to reinterpret some known accreting binaries as civilizations that use stellar energy actively. The hypothesis is similar to the Dyson sphere concept, except the civilization utilizes accretion power instead of solar collectors.
This research aims to refute or confirm the hypothesis. Since all intelligent living systems not only need energy, but actively seek it, we predict that a stellivore would head toward another nearby star once it has almost finished consuming its companion star. This simple idea is testable on accreting binaries that have almost completely consumed their companion star: spider pulsars, both “black widows” and “redbacks”.
Using ATNF and GaiaDR3, we present our recent data collection and analysis. The results suggest a short time to reach a nearby star, as well as a short final distance. We test the hypothesis that the companion star is used as propellant by examining the correlation between (i) the time it takes to reach the closest approach and (ii) the mass of the companion star. We also examine the final angle of approach to the target star, hypothesizing that it should be a suitable angle for gravitational capture. To make all our tests more stringent, we select only spider pulsars in the galactic field, where random collisions rarely occur. To control the hypothesis, we also compute closest approaches using Monte Carlo simulations assuming that the proper motion vectors would have had a random direction. We also conduct other control tests with normal pulsars and non-spider millisecond pulsars.
While distance uncertainties make the analysis delicate, we suggest methods to reduce and mitigate the situation. Goal-directedness is a hallmark of intentionality and intelligence, and if demonstrated with sufficient statistical significance it could serve as a clear life signature.