Will Rigetti report a median two-qubit gate fidelity of at least 99.5% on its 108-qubit Cepheus-1-108Q system before 31 December 2026?
deadline 2026-12-31
confidence low
tier 4 evidence
18%PolySignal estimate
⚠ Evidence cap applied: the model proposed 20%, brought back to 18% for lack of sources solid enough to justify the departure from the base rate.
Resolution criterion
Yes if Rigetti publicly reports (press release, SEC filing, earnings release or investor presentation) a median two-qubit gate fidelity of at least 99.5% measured on Cepheus-1-108Q (or its 108-qubit system), on or before 31 December 2026. Best-pair, single-chiplet or other non-median figures do not count.
Verified starting state
Rigetti announced general availability of Cepheus-1-108Q in April 2026 with a 99.1% median two-qubit fidelity. On its Q2 call (7 August 2026) the median was still about 99.1%; management expects about 99.5% 'later in 2026' and is testing carefully before a cloud rollout. The 108-qubit system had already been delayed once (January 2026).
What pushes it up
- Management expects 99.5% median two‑qubit fidelity later in 2026, indicating a planned improvement and a likely report before the deadline [tier 1]
What pushes it down
- Median fidelity remains at ~99.1% as of August 2026 with no reported improvement, and the 108‑qubit system has already experienced a delay, suggesting technical challenges that could postpone or prevent the target [tier 1]
What would move this number most
Whether Rigetti will actually achieve and publicly report ≥99.5% median two‑qubit fidelity on the 108‑qubit system before 31 Dec 2026
How this number is built
| Deadline | 2026-12-31 |
| Base rate | 10% |
| Best evidence | tier 4 · 0 article(s) used |
| Independent runs | 18 · 18 (spread 0 pts) |
| Confidence | low |
| Evidence cap | applied: 20% brought back to 18% |
| Last revised | 2026-10-14 14:17 |
| Model | openai/gpt-oss-20b (Groq) |