Discoveries in quantum materials, which are characterized by the strongly quantum-
mechanical nature of electrons and atoms, have revealed exotic properties that arise from …

Guided by the above motto (quotation), we review a broad range of issues lying at the
foundations of Density Functional Theory, DFT, a theory which is currently omnipresent in …

The first book dedicated to this new and powerful computational method begins with a
comprehensive description of MCTDH and its theoretical background. There then follows a …

We use the recently developed Heat-bath Configuration Interaction (HCI) algorithm as an
efficient active space solver to perform multiconfiguration self-consistent field calculations …

Here we present a many-body theory based on a solution of the N-representability problem
in which the ground-state two-particle reduced density matrix (2-RDM) is determined directly …

The complete active space self-consistent field (CASSCF) method is the principal approach
employed for studying strongly correlated systems. However, exact CASSCF can only be …

We present a nucleus-dependent valence-space approach for calculating ground and
excited states of nuclei, which generalizes the shell-model in-medium similarity …

The accurate computation of ground and excited states of many-fermion quantum systems is
one of the most consequential, contemporary challenges in the physical and computational …

We present an exact Ansatz for the eigenstate problem of mixed fermion-boson systems that
can be implemented on quantum devices. Based on a generalization of the electronic …

The current work presents a natural orbital functional (NOF) for electronic systems with any
spin value independent of the external potential being considered, that is, a global NOF …