Are Spider Pulsars Goal-Directed? Tests of the Stellivore Hypothesis with Gaia DR3
Creators: name: Vidal, Clément
name: Nilipour, Andy
name: Hoang, John
name: Johnson, Owen A.
Publisher: name: Zenodo
Year: 2023
Subjects: stellivore
SETI
technosignature
close encounters
pulsars
spider pulsars

description: The stellivore hypothesis (Vidal 2014, Chap 9; Vidal 2016) proposes to reinterpret some known accreting binary star systems as Type II civilizations. This hypothesis can be viewed as a variation on the Dyson sphere concept, where the civilization utilizes accretion power instead of solar collectors. Since its inception, no definitive test has been proposed to either 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 evaporated their companion star, which are known as spider pulsars, both “black widows” and “redbacks” (Vidal 2022). Using ATNF and GaiaDR3, we present our recent data collection and analysis aimed at determining whether spider pulsars exhibit goal-directed behavior towards a nearby star. Our analysis suggests a short time to reach a nearby star, as well as a short final distance. We also present correlations between (1) the time it takes to reach the closest approach and (2) 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 effectively do not occur” (Perets Kratter 2012). To control the hypothesis, we also compute closest approaches assuming that the proper motion vectors would have been random. We 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. <br> <strong>References:</strong><br> Perets, Hagai B., and Kaitlin M. Kratter. 2012. “The Triple Evolution Dynamical Instability: Stellar Collisions in the Field and the Formation of Exotic Binaries.” The Astrophysical Journal 760 (2). American Astronomical Society: 99. doi:10.1088/0004-637X/760/2/99. https://doi.org/10.1088%2F0004-637x%2F760%2F2%2F99.<br> Vidal, C. 2014. The Beginning and the End - The Meaning of Life in a Cosmological Perspective. Frontiers Collection. Springer. http://arxiv.org/abs/1301.1648.<br> ———. 2016. “Stellivore Extraterrestrials? Binary Stars as Living Systems.” Acta Astronautica 128: 251–56. doi:10.1016/j.actaastro.2016.06.038. https://zenodo.org/record/164853. ———. 2022. “The Stellivore Hypothesis: An Exploration with Gaia DR3.” Poster presented at the First Penn State SETI Symposium, June 26. doi:10.5281/zenodo.6757507. https://zenodo.org/record/6757507.