Why doesn't IBM have a peer-reviewed two-qubit gate fidelity figure, unlike Google and (partially) Quantinuum?
:first-child]:h-full [&>:first-child]:w-full [&>:first-child]:mb-0 [&>:first-child]:rounded-[inherit] h-full w-full [&>:first-child]:overflow-hidden [&>:first-child]:max-h-full"> Go to QuantumComputing r/QuantumComputing • 15m ago No_Initiative5265 Why doesn't IBM have a peer-reviewed two-qubit gate fidelity figure, unlike Google and (partially) Quantinuum? Hey all, I've been reading up on quantum computing lately (still pretty new to this) and I noticed something that confused me, so hoping someone here can explain it. From what I understand, "fidelity" is basically how accurate a quantum computer is when it runs an operation between two qubits. The closer to 100%, the better. I was comparing a few companies' numbers and noticed something weird: Google's number (99.88%) was published in a real scientific journal (Nature), and other scientists checked it over before it came out. They even said clearly it's an average across the whole chip, not just picking their best-performing pair of qubits. Quantinuum's number (99.921%) went even further — an actual outside lab (Sandia National Labs, part of the US government, not connected to Quantinuum at all) tested it themselves and confirmed it, also published in Nature. IBM's number... doesn't seem to have either of those? Their most recent solid number is from mid-2024 (about 99.5%), and I can't find any outside scientist or lab that double-checked it. And their newest machine (called Nighthawk, announced late 2025) doesn't even have a clear fidelity number published at all — the closest thing I found was some confusing wording about "over 99.9% on more than half the qubit pairs tested," which sounds like it's only talking about some of the qubits, not the whole machine. And here's the part that really got me curious: apparently a separate company (Q-CTRL) tested IBM's Nighthawk machine on a different measurement (called coherence time) and found the real number was way lower than what IBM had originall
