On density and temperature-dependent ground-state and continuum effects in the equation of state for stellar interiors -- A Comment on the paper by S. Arndt, W. Dappen and A. Nayfonov 1998, ApJ 498, 349

Misunderstandings have occurred regarding the conclusions of the paper by S. Arndt, W. Dappen and A. Nayfonov 1998, ApJ 498, 349. At occasions, its results were interpreted as if it had shown basic flaws in the general theory of dynamical screening. The aim of this comment is to emphasize in which connection the conclusions of the paper have to be understood in order to avoid misinterpretations.Comment: Astrophysical Journal (to appear 1 May 1999), 5 page

The uniform electron gas at high temperatures: \emph{ab initio} path integral Monte Carlo simulations and analytical theory

We present extensive new \emph{ab initio} path integral Monte Carlo (PIMC) simulations of the uniform electron gas (UEG) in the high-temperature regime, $8\leq\theta=k_\textnormal{B}T/E_\textnormal{F}\leq128$. This allows us to study the convergence of different properties towards the classical limit. In particular, we investigate the classical relation between the static structure factor $S(\mathbf{q})$ and the static local field correction $G(\mathbf{q})$, which is only fulfilled at low densities. Moreover, we compare our new results for the interaction energy to the parametrization of the UEG by Groth \emph{et al.}~[PRL \textbf{119}, 135001 (2017)], which interpolates between PIMC results for $\theta\leq8$ and the Debye-H\"uckel limit, and to higher order analytical virial expansions. Finally, we consider the momentum distribution function $n(\mathbf{q})$ and find an interaction-induced increase in the occupation of the zero-momentum state even for $\theta\gtrsim32$. All PIMC data are freely available online, and can be used as input for improved parametrizations and as a rigorous benchmark for approximate methods

Günter Kelbg, the Kelbg potential and its impact on quantum plasma theory

Günter Kelbg did remarkable early work in the field of quantum statistical physics, in particular for dense quantum plasmas. In 2022 we celebrated his 100th birthday. On this occasion, we give a brief overview of his main scientific achievements in the field of quantum plasmas, complemented by some biographical background of his research and teaching environment at Rostock University. Kelbg's main achievement is the derivation of a regularized quantum pair potential. We demonstrate that it is still of high relevance for molecular dynamics and quantum Monte Carlo simulations of dense plasmas.Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659Peer Reviewe

Thermodynamics of a correlated confined plasma II. Mesoscopic system

Finite systems of charge carriers con.ned by a harmonic trap are considered. The onion shell model for Coulomb clusters is analyzed and an improved model is proposed which is able to more accurately reproduce the results of numerical experiments. The ground state energy is determined, and the transition to an infinite system is discussed

Thermodynamics of a correlated confined plasma. I. Macroscopic system

We consider classical and quantum systems of charge carriers which are con.ned by a three-dimensional harmonic potential. Thermodynamic functions are determined, and the transition to an uncon.ned system is discussed

Quantum Statistics of Nonideal Plasmas

This book deals with the statistical theory of strongly coupled Coulomb systems. After an elementary introduction to the physics of nonideal plasmas, a presentation of the method of (nonequilibrium) Green's functions is given. On this basis, the dielectric, thermodynamic, transport, and relaxation properties are discussed systematically. Especially, the behavior of bound states in the surrounding plasma (lowering of the ionization energy), the ionization kinetics, and the equation of state of dense partially ionized hydrogen are each carefully investigated. Furthermore, generalized kinetic equations are derived which are also valid for short time scales. They are applied to ultra-fast processes and to plasmas in laser fields