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Sigma_Atheist t1_je2zukl wrote

Then it's useless! 20 qubits are fully simulable on normal computers.

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mescalelf t1_je30cw9 wrote

Yep, it’s a joke; no way it’s gonna do anything useful except act as a training platform that could be just as easily simulated with digital simulation, as you point out.

They’d be better off applying machine learning (in the vein of AlphaFold 2, for instance) on a digital computer for serious R&D.

Well, unless they’ve made one hell of a breakthrough regarding coherence time. Even then, 20 qubits isn’t exactly a lot to work with.

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Nanaki_TV t1_je3bthm wrote

Isn’t there something about alignment or perfect qbits? Where you need more Nonperfect qbits vs perfect to hold data? It’s late. I should sleep.

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mescalelf t1_je3htdl wrote

Not quite the right nomenclature (wording), but wording is often less important than content—and on the content of your question, you’re right.

Unlike digital computers, quantum computers don’t reliably output the right answer—even when they work as well as (we think) they possibly could. Instead, they give a distribution (over multiple runs) of correct and incorrect outputs. , These average out to the right answer if the computation is repeated some number of times.

However, quantum computers produce incorrect outputs much more frequently if a quantum computation is interrupted by some interaction—e.g. a thermal photon. It doesn’t take very much interaction to cause “decoherence”, so many types of quantum computer (including the most popular) have to be cooled to extremely low temperatures. There’s also active research on computational ways of improving fault-tolerance/error-tolerance…unfortunately, even with such methods, thousands of qubits are required to do useful computations. Even with aggressive cooling, none of our quantum computers have been able to hit the necessary qubit counts yet.

Quantum computers aren’t really very impressive or useful with low numbers of qubits. The computational power of digital computers scales roughly linearly with respect to the number of computational transistors. The representational complexity of a quantum computer doubles each time a qubit is added; this doesn’t translate nicely to equivalent computational power, but quantum computers do still have much steeper (exponential) scaling for some types of computational problem. Unfortunately, systems of many entangled qubits are much less stable than smaller entangled systems…so we can’t make good use of quantum computers until we can improve coherence time and/or fault tolerance a good deal.

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uishax t1_je43wfy wrote

Quantum computers, like nuclear fusion, look like they could use a heavy dose of AI-assisted research from GPT-7/8.

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mescalelf t1_je6kc65 wrote

Yep, 100%. They’re both technically soluble, but are, apparently, very nuanced problems. AI (even purpose-built narrow AI) is great with those.

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