What a misleading title. First of all the title suggests that all supercivilizations build Dyson spheres, so that the absence of Dyson spheres implies the abse

What a misleading title. First of all the title suggests that all supercivilizations build Dyson spheres, so that the absence of Dyson spheres implies the absence of any supercivilization. But in the article itself we can already find scenario's for other kinds of supercivilizations. Second, the fact that we didn't find any sign of a Dyson sphere, doesn't prove that they are not there. We definitely can not see every (Dyson) star in those 100,000 galaxies, so even if supercivilizations require Dyson spheres, they still might be there and we could just have missed them.