Dysonian SETI
In a 1960 paper, Freeman Dyson proposed the idea of a Dyson sphere, a type of extraterrestrial artifact able to be searched for and studied at interstellar distances. Following that paper, several searches have been conducted.
In a 2005 paper, Luc Arnold proposed a means of detecting smaller, though still mega-scale, artifacts from their distinctive light curve signature. (see Astroengineering).
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