How Advanced Alien Civilizations Would Conquer the Galaxy
Makoto Inoue, Hiromitsu Yokoo
We describe a new system for a society of highly advanced civilizations around a super massive black hole (SMBH), as an advanced Type III “Dyson Sphere“, pointing out an efficient usage of energy for the advanced civilizations. SMBH also works as a sink for waste materials. Here we assume that Type III civilisations of Kardashev classification  form a galactic club  in a galaxy, and the energy from the SMBH will be delivered to the club members, forming an energy control system similar to power grids in our present society. The energy is probably transmitted by a sharp beam with coherent electro-magnetic waves, which provide a new concept for the search for extraterrestrial intelligence (SETI) via detection of such energy transmission signals. This expands the search window for other intelligences within the Universe….
Figure 1 shows a schematic picture of the power plants and others around SMBH. The condition around SMBH is very promising for an advanced intelligence to manage energy issues in terms of both energy generation and disposition.This idea comes from a combination of Type III and Dyson Sphere. The strong radiation from the accretion disk rotating around SMBH is mainly used, and the waste energy is returned toward the SMBH. The available energy is huge compared to Dyson Sphere of stellar scale, and this type ofcivilization could be called Type III Dyson Sphere. The search for this type of civilization, however, would not likely be revealed from “unintended” communication signal, but detection by coherent radiation from power stations may be more promising….
Read more: http://arxiv.org/pdf