相关论文: Particle-number conservation within self-consisten…

We use the Quasiparticle Random Phase Approximation (QRPA) and the Skyrme interactions SLy4 and SkM* to systematically calculate energies and transition strengths for the lowest 2+ state in spherical even-even nuclei.The SkM* functional,…

A Shell-model-Like APproach (SLAP) suggested to treat the pairing correlations in relativistic mean field theory is introduced, in which the occupancies thus obtained having been iterated back into the densities. The formalism and numerical…

Fractional occupation numbers can be used in density functional theory to create a symmetric Kohn-Sham potential, resulting in orbitals with degenerate eigenvalues. We develop the corresponding perturbation theory and apply it to a system…

Representing a strongly interacting multi-particle wave function in a finite product basis leads to errors. Simple rescaling of the contact interaction can preserve the low-lying energy spectrum and long-wavelength structure of wave…

We present an optimized random phase approximation method (optRPA26) that significantly improves upon conventional RPA. The method employs an empirically constructed hybrid functional to generate DFT orbitals to evaluate the RPA correlation…

The self-consistent Relativistic Quasiparticle Random Phase Approximation (RQRPA) is extended by the quasiparticle-phonon coupling (QPC) model using the Quasiparticle Time Blocking Approximation (QTBA). The method is formulated in terms of…

Based on the path integral representation of the partition function of a many body system with separable two body interaction we propose a systematic extension of the perturbed static path approximation (PSPA) to lower temperatures.…

The ground state equilibrium properties of copper-gold alloys have been explored with the state of art random phase approximation (RPA). Our estimated lattice constants agree with the experiment within a mean absolute percentage error…

The particle-hole symmetry (equivalence) of the full shell-model Hilbert space is straightforward and routinely used in practical calculations. In this work we show that this symmetry is preserved in the subspace truncated at a certain…

The effect of the inclusion of ground state correlations into the QRPA equation of motion for the two-neutrino double beta ($\beta\beta_{2\nu}$) decay is carefully analyzed. The resulting model, called renormalized QRPA (RQRPA), does not…

We use a continued fraction approximation to calculate the RPA response function of nuclear matter. The convergence of the approximation is assessed by comparing with the numerically exact response function obtained with a typical effective…

The ground-state correlation energy calculated in the random-phase approximation (RPA) is known to be identical to that calculated using a subset of terms appearing in coupled-cluster theory with double excitations. In particular, this…

A central challenge in machine learning is to understand how noise or measurement errors affect low-rank approximations, particularly in the spectral norm. This question is especially important in differentially private low-rank…

The numerical accuracy of particle-based approximations in Smoothed Particle Hydrodynamics (SPH) is significantly affected by the spatial uniformity of particle distributions, especially for second-order derivatives. This study aims to…

We propose an approximation of nonlinear renewal equations by means of ordinary differential equations. We consider the integrated state, which is absolutely continuous and satisfies a delay differential equation. By applying the…

With increasing inter-electronic distance, the screening of the electron-electron interaction by the presence of other electrons becomes the dominant source of electron correlation. This effect is described by the random phase approximation…

We show how the longstanding problem of the collapse of the charge-exchange QRPA near the physical value of the force strength can be circumvented. This is done by including the effect of ground state correlations into the QRPA equations of…

The first, to our knowledge, calculation of neutrinoless double beta decay ($0\nu\beta\beta$-decay) matrix elements within the self-consistent renormalised Quasiparticle Random Phase Approximation (SRQRPA) is presented. The contribution…

The hierarchy of pure states (HOPS) is a wavefunction-based method which can be used for numerically modeling open quantum systems. Formally, HOPS recovers the exact system dynamics for an infinite depth of the hierarchy. However,…

A scaling theory of replica symmetry breaking (RSB) in the SK-model is presented in the framework of critical phenomena for the scaling regime of small inverse RSB-orders, small temperatures, small magnetic fields, and near opposite…