We present numerical results for the equation of state of an infinite chain of hydrogen atoms.
A variety of modern many-body methods are employed, with exhaustive cross-checks and …

The Hubbard model represents the fundamental model for interacting quantum systems and
electronic correlations. Using the two-dimensional half-filled Hubbard model at weak …

Precise calculations of dynamics in the homogeneous electron gas (jellium model) are of
fundamental importance for design and characterization of new materials. We introduce a …

We present a simple trick that allows us to consider the sum of all connected Feynman
diagrams at fixed position of interaction vertices for general fermionic models, such that the …

Sign problem in quantum Monte Carlo (QMC) simulation appears to be an extremely hard
yet interesting problem. In this article, we present a pedagogical overview on the origin of …

We propose a systematic approach to the nonequilibrium dynamics of strongly interacting
many-body quantum systems, building upon the standard perturbative expansion in the …

We demonstrate that a summing up series of Feynman diagrams can yield unbiased
accurate results for strongly correlated fermions even when the convergence radius …

The mystery of the infamous sign problem in quantum Monte Carlo simulations mightily
restricts applications of the method in fermionic and frustrated systems. A recent work …

Sign problems in fermion quantum Monte Carlo (QMC) simulation appears to be an
extremely hard problem. Traditional lore passing around for years tells people that when …

We develop a numerically exact method for the summation of irreducible Feynman diagrams
for fermionic self-energy in the thermodynamic limit. The technique, based on the …