Evolutionary and Observational Consequences of Dyson Sphere Feedback

Abstract

The search for signs of extraterrestrial technology, or technosignatures, includes the search for objects which collect starlight for some technological use, such as those composing a Dyson sphere. These searches typically account for a star's light and some blackbody temperature for the surrounding structure. However, such a structure inevitably returns some light back to the surface of its star, either from direct reflection or thermal re-emission. In this work, we explore how this feedback may affect the structure and evolution of stars, and when such feedback may affect observations. We find that in general this returned light can cause stars to expand and cool. Our MESA models show that this energy is only transported toward a star's core effectively by convection, so low mass stars are strongly affected, while higher mass stars with radiative exteriors are not. Ultimately, the effect only has significant observational consequences for spheres with very high temperatures (much higher than the often assumed ∼300 K) and/or high specular reflectivity. Lastly, we produce color-magnitude diagrams of combined star-Dyson sphere systems for a wide array of possible configurations.

UAP Research in Germany: Single Case Studies, Data Management, Understanding of “Strangeness”

“…Außerdem müssen selbst für weit fortgeschrittene ETs die Hauptsätze der Thermodynamik gelten (Energieerhaltung, Entropiezunahme). Daher besteht durchaus eine Chance, die Abwärme ihres Energieverbrauchs zu entdecken, wenn er stellare, interstellare oder gar galaktische Ausmaße angenommen hat (Balbi & Ćirković, 2021;Ćirković, 2006Dyson, 1960;Huston & Wright, 2022;Lingam & Loeb, 2020;Matloff, 2017;Osmanov 2018;Osmanov & Berezhiani, 2018;Wright, 2020aWright, , 2023Zackrisson et al, 2018;Zuckerman, 2022a). Dahingehend durchforstet wurden bereits Infrarotquellen-Himmelskataloge von Weltraumteleskopen wie IRAS (Infrared Astronomical Satellite), WISE (Wide-field Infrared Survey Explorer) und Spitzer, die über 100.000 Sterne und Galaxien verzeichnen (Timofeev et al, 2000;Carrigan, 2009;Wright et al, 2014;Griffith et al, 2015).…”