Quantum simulation advantage stops being a one-paper verdict: QSim-Arena agents cut certified runtime 21 to 185-fold in a week
Judging where quantum dynamics simulation wins depends on two method portfolios that keep moving, so a crossover fixed in a single paper ages quickly. QSim-Arena turns that assessment into a closed loop maintained by AI agents: agents convert published techniques into executable components, admit a method only after it reproduces a published number, and have results checked by a lane that did not produce them. Starting from the fault-tolerant crossover route of Sun et al., agents introduced three published techniques within a week, lowering certified runtime on four Hamiltonian families at sixteen qubits (twelve for the hydrogen chain) by factors of 21, 23, 25 and 185, and measured runtime fourfold on every family.