A nested shell computation architecture: each layer absorbs the inner shell's waste heat, computes, and radiates outward. Plan the number of layers, temperature cascade, ops/joule efficiency, and total computation budget.
| Shell | Temp (K) | Carnot η | Ops/J (Landauer) | Ops/s | Cum. Ops/s |
|---|
Outer shells operate at lower temperature — slower per operation but more efficient (Landauer). Inner shells dominate raw throughput; outer shells dominate efficiency.
Architecture: A Matrioshka Brain (MB) wraps a power source (star or black hole) in N concentric shells. The innermost shell at temperature T₁ receives power P. It operates at Carnot efficiency η₁ = 1 − T₂/T₁ (where T₂ is the next shell), and radiates the remainder outward. This tool models a geometric temperature cascade: T_k = T₁ × r^(k−1) where r is the temperature ratio between shells, chosen so the outermost shell operates at 3 K (near the CMB floor — colder would require active cooling at a net energy cost).
Ops/J (Landauer limit): Each irreversible bit erasure costs at minimum k_B T ln 2 joules of heat (Landauer 1961). The maximum reversible operations per joule is therefore 1/(k_B T ln 2). At T = 3 K (outer shell), this is ~3.5 × 10²² ops/J. At T = 5,000 K (inner shell, solar surface temperature), it drops to ~2 × 10¹⁹ ops/J. The outer shells are ~1,000× more computationally efficient per joule, but have lower power throughput if the architecture progressively extracts work at each layer.
Ops/s per shell: Each shell extracts work η_k × P_k (where P_k is the power incident on shell k) and uses that to compute. Ops/s = (η_k × P_k) / (k_B T_k ln 2). The total ops/s sums over all shells — though in practice the power available to each outer shell is diminished by inner shell extraction.
ωCen IMBH context: A BZ-powered IMBH at ωCen in quiescent mode radiates ~10³⁶ W (see the BZ/Kardashev Power Calculator). Wrapping this in a 5-shell MB structure at 1,000 K inner temperature yields total ops/s far exceeding any stellar MB. The outermost shell operating at 3 K would be undetectable in mid-infrared but could produce a distinctive cascade signature.
References: Landauer 1961 IBM J. Res. Dev. 5:183 · Lloyd 2000 Nature 406:1047 · Sandberg, Armstrong & Ćirković 2017 (arXiv:1705.03394) · Dyson 1960 Science 131:1667