A review is given on the foundations and applications of non-Hermitian classical and
quantum physics. First, key theorems and central concepts in non-Hermitian linear algebra …

In the early 1970s, Wilson developed the concept of a fully nonperturbative renormalization
group transformation. When applied to the Kondo problem, this numerical renormalization …

The treatment of high‐dimensional problems such as the Schrödinger equation can be
approached by concepts of tensor product approximation. We present general techniques …

Numerous correlated electron systems exhibit a strongly scale-dependent behavior. Upon
lowering the energy scale, collective phenomena, bound states, and new effective degrees …

We present the reaction-coordinate polaron-transform (RCPT) framework for generating
effective-Hamiltonian models to treat nonequilibrium open quantum systems at strong …

Current nonequilibrium Monte Carlo methods suffer from a dynamical sign problem that
makes simulating real-time dynamics for long times exponentially hard. We propose a new …

We introduce an efficient method to simulate the dynamics of an interacting quantum
impurity coupled to noninteracting fermionic reservoirs. Viewing the impurity as an open …

We show how spectral functions for quantum impurity models can be calculated very
accurately using a complete set of discarded numerical renormalization group eigenstates …

We present a tree-tensor-network-based method to study strongly correlated systems with
nonlocal interactions in higher dimensions. Although the momentum-space and quantum …

A general framework for non-abelian symmetries is presented for matrix-product and tensor-
network states in the presence of well-defined orthonormal local as well as effective basis …