We establish reflection positivity for Gibbs trace states defined by a certain class of Hamiltonians that describe the interaction of Majoranas on a lattice. These Hamiltonians may include many-body interactions, as long as the signs of the associated coupling constants satisfy certain restrictions. We show that reflection positivity holds on an even subalgebra of Majoranas.

The structure of nuclei far off β-stability is investigated by nuclear many-body theory. In-medium interactions for asymmetric nuclear matter are obtained by (Dirac-) Brueckner theory thus establishing the link of nuclear forces to free space interactions. HFB and RPA theory is used to describe ground and excited states of nuclei from light to heavy masses. In extreme dripline systems pairing a...

We obtain the exact ground state and a part of the excitation spectrum in one dimension on a line and the exact ground state on a circle in the case where N particles are interacting via nearest and nextto-nearest neighbour interactions. Further, using the exact ground state, we establish a mapping between these N -body problems and the short-range Dyson models introduced recently to model inte...

Theoretical approach to investigate human-human interaction in society performed using a many-body theory including human-human interaction. The advertisement is treated as an external force. The word of mouth (WOM) effect is included as a two-body interaction between humans. The rumor effect is included as a three-body interaction between humans. The parameters to define the strength of human ...

We calculate the effect of many-body interactions in nuclear matter on the spectral function of ρ and ω meson. In particular, we focus on the role played by baryon resonances in this context.

A hierarchical family of analytical Born–Oppenheimer potential energy surfaces has been developed for the H1H2 system. Ab initio calculations of near full configuration interaction ~FCI! quality ~converged to within '1 mEh! were performed for a set of 4067 configurations with the aug-cc-pVDZ, aug-cc-pVTZ, and aug-cc-pVQZ basis sets. The complete basis set ~CBS! limit energies were obtained usin...

The many-body expansion (MBE) is an efficient tool which has a long history of use for calculating interaction energies, binding lattice and so on. In the past, applications MBE to correlation energy have been unfeasible large systems, but recent improvements computing resources sparked renewed interest in capturing using generalized $n$-th order Bethe-Goldstone equation. this work, we extend a...

Semilocal density functional theory generally fails in stabilizing polarons, because of its spurious inclusion the electron self-interaction. This work addresses concepts many-body and one-body self-interaction, which are found to be connected through dielectric constant within a unified theoretical formulation. The superiority self-interaction is demonstrated, resulting robust polaron formatio...