Dyson brain: ``Uranos''

Uranos gradually emerged when the matter of a solar system was converted by intelligent life into a Dyson sphere surrounding its sun-like star at a distance of 1 AU. It consists of numerous independently orbiting structures, ranging from large (hundreds of kilometers) solar collectors to microscale devices moving between the structures for repair and adjustment.

The efficiency of converting solar energy to work is around 30%, giving $3\cdot10^{25}$ Watt of available energy. The working temperature for an unshielded object in an 1 AU orbit is 395K. The number of bit-erasures that can be achieved under these conditions is $7.9\cdot10^{45}$ bits/second.

The total amount of matter available in the solar system (disregarding hydrogen and helium) beside the sun is $\approx 1.7 \cdot 10^{26}$ kg [66]. If the energy collecting system is assumed to hold a fairly minor fraction (1%) of the total mass, and assuming molecular densities, then Uranos can contain up to 10⁵² bits. Assuming processing nodes of the same type as Zeus, we get 10³⁹ nodes and 10⁵¹ operations per second.

The internal delays between distant nodes are on average 660 seconds. Assuming the same picosecond switching as in Zeus gives $S\approx 6.7\cdot 10^{14}$, suggesting even less synchronization than Zeus.

Where Uranos really outperforms Zeus is information production/destruction; the high energy throughput makes it possible to dissipate 10²² times as many bits as Zeus. It might make sense to keep Zeus-like structures in orbit outside Uranos to act as information repositories and the Dyson shell itself for processing.

The main limitation of Uranos is the availability of matter, and the amount of energy that can be extracted from the sun.