Among various algorithms designed to exploit the specific properties of quantum computers
with respect to classical ones, the quantum adiabatic algorithm is a versatile proposition to …

Providing an optimal path to a quantum annealing algorithm is key to finding good
approximate solutions to computationally hard optimization problems. Reinforcement is one …

The standard quantum annealing algorithm tries to approach the ground state of a classical
system by slowly decreasing the hopping rates of a quantum random walk in the …

We propose the variational quantum cavity method to construct a minimal energy subspace
of wavevectors that are used to obtain some upper bounds for the energy cost of the low …

The fermion sign problem, the biggest obstacle in quantum Monte Carlo calculations, is
completely solved in this paper. Here, we find a strategy, in which the contribution from those …

We consider an interacting system of spin variables on a loopy interaction graph, identified
by a tree graph and a set of loopy interactions. We start from a high-temperature expansion …

Given a locally consistent set of reduced density matrices, we construct approximate density
matrices which are globally consistent with the local density matrices we started from when …

The fermion sign problem, the biggest obstacle in quantum Monte Carlo calculations, is
completely solved in this paper. Here, we find a strategy, in which the contribution from those …

We study the inverse problem of constructing an appropriate Hamiltonian from a physically
reasonable set of orthogonal wave functions for a quantum spin system. Usually, we are …

Any spanning tree in a loopy interaction graph can be used for communicating the effect of
the loopy interactions by introducing messages that are passed along the edges in the …