where the complex-valued are time-dependent variational parameters, denotes a many-body configuration and are time-independent operators that define the specific ansatz. The time evolution of the parameters can be found upon imposing a variational principle to the wave function. In particular one can show that the optimal parameters for the evolution satisfy at each time the equation of motion
where is the Hamiltonian of the system, are connected averages, and the quantum expectation values are taken over the time-dependent variational wave function, i.e., .
In analogy with the Variational Monte Carlo approach and following the Monte Carlo method for evaluating integrals, we can interpret
as a probability distribution function over the multi-dimensional space spanned by the many-body configurations . The Metropolis–Hastings algorithm is then used to sample exactly from this probability distribution and, at each time , the quantities entering the equation of motion are evaluated as statistical averages over the sampled configurations. The trajectories of the variational parameters are then found upon numerical integration of the associated differential equation.
G. Carleo; F. Becca; M. Schiró & M. Fabrizio (2012). "Localization and glassy dynamics of many-body quantum systems". Sci. Rep. 2: 243. arXiv:1109.2516. Bibcode:2012NatSR...2E.243C. doi:10.1038/srep00243. PMC3272662. PMID 22355756.
G. Carleo; F. Becca; L. Sanchez-Palencia; S. Sorella & M. Fabrizio (2014). "Light-cone effect and supersonic correlations in one- and two-dimensional bosonic superfluids". Phys. Rev. A. 89 (3): 031602(R). arXiv:1310.2246. Bibcode:2014PhRvA..89c1602C. doi:10.1103/PhysRevA.89.031602. S2CID 45660254.
G. Carleo (2011). Spectral and dynamical properties of strongly correlated systems (PhD Thesis). pp. 107–128.