Table 2.
Problem | Error model | Assumption | Classical run-time | Quantum run-time |
---|---|---|---|---|
Provable noisy quantum advantage over Krylov Subspace/Exact methods | ||||
Dynamics | General errors | None | O(poly(δ−1)) | |
Ground state | Coherent | • Stable gap | O(poly(δ−1)) | |
Hamiltonian | • Logarithmic convergence | |||
errors | • Adiabatic path with a gap > Ω(1/poly(n)) | |||
Fixed points | General errors | Rapid mixing | O(poly(δ−1)) | |
Conjectured noisy quantum advantage | ||||
Ground states | Coherent | • Stable Ω(1/poly(n)) gap | O(poly(δ−1)) | |
Hamiltonian | • Power-law convergence | |||
errors | • Adiabatic path with a gap > Ω(1/poly(n)) | |||
Fixed points | Coherent and incoherent Markovian errors |
• Reaches ε—close to fixed point in O(poly(n, 1/ε)) time • Power-law convergence |
O(poly(δ−1)) |
For classical run-times, we only consider Krylov subspace methods or exact diagonalization as the classical algorithm for the provided lower bounds, and not heuristics which do not have rigorous convergence guarantees. Note that suppresses factors.