Spheres

Dyson spheres also exist in the Culture universe but are only mentioned in passing and are simply called "Spheres". Three spheres are recorded as having been destroyed in the Idiran-Culture war.

In Matter, the Morthanveld Nestworld of Syaung-un is a "Sphere World" consisting of a complex, recursive arrangement of transparent tubes within tubes, all revolving around a small central star. The Nestworld is alleged to contain forty trillion Morthanveld, more intelligent beings than on all the Culture and associated worlds put together. There are also noted to be other Nestworlds, but none as big as Syaung-un.^{[citation needed]}