Dust to Dust: Prospects for Passive Technosignatures as Relics of ETI

Abstract

Technological societies are separated in time, not just space -- that is the lesson of the Drake equation. Might the best way to seek them be to find technosignatures that persist long after their creators? I present work I and my collaborators have done on the idea of passive technosignatures, requiring no upkeep from an active society. These range from microscopic to galactic in scale, including specular reflections from shiny artifacts in the Solar System, lens flares from X-ray binaries, and the survivability of Dyson swarms. I discuss prospects for detecting these technosignatures. In the end, what we may be left with are the end products of collisional cascades: dust.