Source: /cirosantilli/quantum-computing-is-hard-because-we-want-long-coherence-but-fast-control

= Quantum computing is hard because we want long coherence but fast control
{wiki}

Mentioned e.g. at:
* https://youtu.be/t5nxusm_Umk?t=176
* https://youtu.be/xjlGL4Mvq7A?t=169

These are two conflicting constraints:
* long <coherence times>: require isolation from external world, otherwise observation destroys quantum state
* <state initialization (quantum computing)>[fast control] and <readout (quantum computing)>: require coupling with external world