Quantum Computers Are Analog Computers

Google continues to experiment with quantum computing
<https://arstechnica.com/science/2019/09/paper-leaks-showing-a-quantum-computer-doing-something-a-supercomputer-cant/>.
This latest result (albeit preliminary) sounds impressive:

    But that seriously understates what's going on here. Every
    calculation that's done on a quantum computer will end up being a
    measurement of a quantum system. And in this case, there is simply
    no way to get that probability distribution using a classical
    computer. With this system, we can get it in under 10 minutes, and
    most of that time is spent in processing that doesn't involve the
    qubits. As the researchers put it, "To our knowledge, this
    experiment marks the first computation that can only be performed
    on a quantum processor."

but it is still just reinforcing the point I made earlier
<https://list.waikato.ac.nz/hyperkitty/list/[email protected]/thread/KZNHRQBERD3UUWQ53DQDGXMDLCIXBZMX/>,
that quantum computers are just a reboot of the old idea of “analog”
computers. These are able to do fast simulations of physical systems
(in this case, a quantum probability distribution), to limited
precision. But they continue to be useless for number-theoretic
calculations, such as factoring large integers. Or code cracking.
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