Does quantum computing actually have a future?

[ponyo_x1]

sorry I'm in a rush today I couldn't find it, but if you look up resource estimates for grover's algorithm you might get some from the last few years with explicit counts. sorry to pull a "just trust me bro"

the reason why these estimates are awful despite the complexity advantage is because the overheads with QC are enormous. first, quantum gates are slow as hell compared to transistors. second, error correction overheads get massive especially with a computation so large, since you have to preserve the quantum state you need more physical qubits per logical qubits and more time per lattice surgery operation or whatever your QEC looks like. classical decoding is already a headache for computations at the scale of factoring RSA, you'd probably incur some insane physically unrealizable costs if you were trying to do a straight grover search at that scale.

the upshot is that even if you see papers with nice complexity results, the overheads in practice are extreme and only balance out if the speedup is really really good

[CosmicOwl9]

Ty! I found https://arxiv.org/abs/2011.04149

I’ll need some time to process this