Verifying analog quantum simulators beyond classical reach

4 problems

• Has an analog quench simulation exceeded classical computation?

  Contested

  A 2025 experiment claimed a quantum annealer simulated magnetic dynamics that no supercomputer could match. Classical simulation groups replied with algorithms that may do the same job.

• Which simulator observables have size-independent error bounds?

  Partially resolved

  Small errors in the controls might add up across many atoms and ruin a big simulation. The question is which measured quantities stay accurate no matter how big the system grows.

• A classically hard equilibrium observable an analog simulator can reach

  Open

  Hot quantum systems turn out to be easy for classical computers. The question is whether any cooled simulator can reach a regime that is both hard for classical methods and accessible to the hardware.

• A scalable protocol to certify analog simulator outputs

  Open

  Checking a simulator by calculation fails exactly where the simulator is useful. The task is a test that needs only modest classical computing and a reasonable number of measurements.