4 ms·
> once you cross the fault tolerant threshold If we cross the threshold. Until then, adding a qubit requires halving the noise floor, so the Moore's law equiva
by akvadrako 3y ago
> once you cross the fault tolerant threshold
If we cross the threshold. Until then, adding a qubit requires halving the noise floor, so the Moore's law equivalent to exponential scaling is basically adding a fixed number of qubits per year.
- jessriedel 3y agoNot sure what you're saying. Are you suggesting that gates surpassing the fault tolerant threshold will never be achieved? The vast majority of experts disagree with this. Without fault tolerance, you have a hard wall on circuit depth because errors grow exponentially with depth. You can't make up for this by adding any number of qubits. "Halving the noise floor" means...what, improving gate fidelity?
- akvadrako 3y agoThat's what I'm saying. I don't really mean never, but I don't see why we have good reason to believe we'll reach that threshold this millenium. Until then, the best we can do is if you half the noise floor (or double the fidelity) you can add roughly one ideal qubit.
- jessriedel 3y agoYou can't double the fidelity because it's already much larger than 1/2, and if you mean halving the infidelity then this doubles the depth of the deepest circuit you can perform (not just increasing it by one layer). And none of that leads to an ideal qubit. The most obvious reason to suppose the fault tolerance threshold will be crossed is that simple extrapolation of progress predicts it will.
- pyinstallwoes 3y agoThe vast majority of experts are being employed to say this. There is no demonstrable evidence of physical computation to the contrary.
- jessriedel 3y agoTenured professors who have been working in the field for decades before you ever heard about it in the news, and who have been consistently deeply critical of quantum computing hype despite negative professional and financial penalties from doing so, nonetheless still agree overwhelmingly that it will happen. You can't just believe the opposite of what swindlers are arguing and expect that to be right.
- pyinstallwoes 3y agoOn one hand I can make a joke that you are defending the only job on Earth that not only gets paid but can't get fired past a certain point due to their 'tenure.' On the other hand I can make a nod in the direction of the decades of expertise any one can build in a chamber of vapor ware with the hope that it will distill into something useful. As critical as I am, I of course congratulate anyone on taking on such difficult innovation. Nonetheless, there is no physical evidence it will amount to anything thus far. It is purely hypothetical, and the only thing theoretical in justification is the fictitious proof of its use through mathematical modeling which is not physical reality and thus closer to building a virtualized computer in a MMO that mimics Earth saying you get to play as a martian using some weird technology while it runs on classical computing.
- jessriedel 3y agoSo people who have financial interests can't be trusted, but also people who don't have financial interest can't be trusted. All new tech starts as purely hypothetical. (Not to mention concrete milestones like quantum supremacy, gate infidelity trends, etc.)
- pyinstallwoes 3y agoYeah that's why most startups fail. Rarely do startups exist for over 40 years with no physical proof of the idea working and just a simulation of it that fundamentally undermines its reality and even more rarely are there people who don't work at those startups who defend them as if compelled by some strange force.