FAQ on Microsoft's topological qubit thing

I remain curious if you can actually calculate anything with these gadgets? I mean can it add 2 and 2 or work out the factors of 30 or anything?

This experiment only created one qubit, so no.

The experiment with lots of qubits... technically yes they can do things. I think the factoring record is 21. But you might be disappointed a) when you see that most algorithms using quantum computers require conventional computational to transform the problem before and after the quantum steps b) when you learn we only have a few quantum algorithms, the are not general calculation machines and c) when you look under the hood and see that the error correcting stuff makes it actually kinda hard to tell how much is really being done by the actual quantum device.

Thanks for the reply. I've always been a bit puzzled from my limited knowledge of quantum mechanics as to how they are supposed to work. I mean you make a measurement on a quantum system and sure the probability amplitude is the result of adding up all sorts of possible paths but you still only get the one measurement out which I'm not sure how that's supposed to tell you much. All a bit beyond me.

Does https://scottaaronson.blog/?p=208 help?

(Also, the factoring-21 result is from 2012, and may have been surpassed since then depending on how you count. Recent quantum-computing research has focused less on factoring numbers and more on problems like random circuit sampling where it's easier to get meaningful results with the noisy intermediate-scale machines we have today. Factoring is hard mode because you have to get it exactly right or else it's no good at all.)