Neural quantum states (NQS) represent an emerging and promising tool for simulating many-body quantum systems, especially in condensed matter. These methods combine the flexibility of neural network-based parametrizations with Monte Carlo sampling techniques to construct variational representations of wave functions. Their recent application has allowed addressing complex challenges in systems such as frustrated quantum magnets, interacting lattice fermions, and non-equilibrium dynamics, where traditional methods encounter significant limitations.
Progress in NQS relies on optimizing neural network architectures, imposing physical symmetry constraints, developing efficient optimization methods, and sophisticated sampling strategies. These improvements have enabled state-of-the-art calculations that extend the reach of classical simulations in strongly correlated quantum matter. The ability of NQS to model complex wave functions makes them a powerful alternative to conventional approximations.
However, significant challenges remain. These include the difficulty of learning non-trivial sign and phase structures, controlling the variational bias inherent in these methods, rigorously enforcing physical symmetries, scaling optimization to large neural networks, and achieving stable real-time evolution. Despite these barriers, NQS open new avenues for exploring complex quantum phenomena and are expected to continue expanding the capabilities of computational simulation in condensed matter physics.