This Also Blows Me Away

A Matrioshka Brain is a hypothetical megastructure, based on the Dyson sphere, of immense computational capacity. It is an example of a Class B stellar engine, employing the entire energy output of a star to drive computer systems.

Such a structure would be composed of a collection of one or more (typically more) Dyson spheres built around a star, and nested one inside another. A significant percentage of the shells would be composed of nanoscale computers (see molecular-scale computronium). These computers would be at least partly powered by the energy exchange between the star and interstellar space. A shell (or component, should a Dyson swarm be the design model used) would absorb energy radiated onto its inner surface, utilize that energy to power its computer systems, and re-radiate the energy outwards. The nanoscale computers of each shell would be designed to run at different temperatures; shells or components at the core could be nearly as hot as the central star, while the outer layer of the Matrioshka Brain could be almost as cool as interstellar space.