SWSN SCIENTIFIC REVIEW SERIES SWSN-SCI/ORP-2035-04-R3
Figure 3: Mean restoration fidelity in the conditional phase-noise stress test. This is an illustrative
control model, not a reproduction of Ref. [1] and not evidence for macroscopic time reversal.
6 Why a quantum computer is requested
Exact classical state-vector storage scales as2N . At complex128 precision, a state vector alone
requires approximately16 × 2N bytes: about 18 PB forN = 50 and 18 EB forN = 60 , before
operators, trajectories, optimization states and error-correction overhead. Tensor-network
and reduced-order methods can drastically reduce cost when structure permits; therefore
exponential storage is not, by itself, proof that a quantum computer will provide advantage.
The resource request is narrower. We request controlled access to the national quantum sys-
tem to test whether the ORPHEUS inverse-control subproblem can be encoded as a tractable
quantum simulation or hybrid optimization task on a restricted model class. The success cri-
terion is a measurable reduction in wall-clock or sample complexity against the best avail-
able classical baseline. If no advantage appears, the quantum-compute branch of the pro-
gram is to be closed.
7 Astrophysical energy reservoir
A rotating Kerr black hole contains extractable rotational energy. The irreducible-mass re-
lation gives
Mirr
M =
√
1 +
√
1 − a2∗
2 , (7)
so the ideal rotational reservoir is
Erot = ( M − Mirr) c2. (8)
For a∗ → 1, the ideal reservoir approaches 29.3% ofMc2. Penrose-process and related mecha-
nisms show that energy extraction from a rotating black hole is permitted by general relativ-
ity in principle, although practical engineering at astrophysical scales is entirely unresolved
[8, 9, 10].
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