Reconstruction of Randomly Sampled Quantum Wavefunctions using Tensor Methods

We propose and test several tensor network based algorithms for reconstructing the ground state of an (unknown) local Hamiltonian starting from a random sample of the wavefunction amplitudes. These algorithms, which are based on completing a wavefunction by minimizing the block Renyi entanglement entropy averaged over all local blocks, are numerically demonstrated to reliably reconstruct ground states of local Hamiltonians on 1D lattices to high fidelity, often at the limit of double-precision numerics, while potentially starting from a random sample of only a few percent of the total wavefunction amplitudes.