Comment on “Density and physical current density functional theory”

Comment on "Density and Physical Current Density Functional Theory"

Stochastic time-dependent current-density-functional theory.

A time-dependent current-density-functional theory for many-particle systems in interaction with arbitrary external baths is developed. We prove that, given the initial quantum state |Psi0> and the particle-bath interaction operator, two external vector potentials A(r,t) and A'(r,t) that produce the same ensemble-averaged current density, j(r,t), must necessarily coincide up to a gauge transfor...

Current Densities in Density Functional Theory

It is well known that any given density ρ(x) can be realized by a determinantal wave function for N particles. The question addressed here is whether any given density ρ(x) and current density j(x) can be simultaneously realized by a (finite kinetic energy) determinantal wave function. In case the velocity field v(x) = j(x)/ρ(x) is curlfree, we provide a solution for all N , and we provide an e...

Perspective on density functional theory.

Density functional theory (DFT) is an incredible success story. The low computational cost, combined with useful (but not yet chemical) accuracy, has made DFT a standard technique in most branches of chemistry and materials science. Electronic structure problems in a dazzling variety of fields are currently being tackled. However, DFT has many limitations in its present form: too many approxima...

From Density Functional Theory to Density Matrix Functional Theory

Coupled cluster methods are considered among the most accurate tools in electronic structure theory. Nonetheless relatively limited attempt seems to have been made to extend their applicability to the description of the core-excitation phenomena that are behind largely used spectroscopic techniques like x-ray absorption spectroscopy and x-ray circular dichroism. As a first step to redeem for su...