Weighted-Graph-Theoretic Methods for Many-Body Corrections within ONIOM: Smooth AIMD and the Role of High-Order Many-Body Terms

2021 ◽  
Author(s):  
Juncheng Harry Zhang ◽  
Timothy C. Ricard ◽  
Cody Haycraft ◽  
Srinivasan S. Iyengar
Keyword(s):  
Weighted Graph ◽  
High Order ◽  
Many Body ◽  
Graph Theoretic

scholarly journals Universal relations for ultracold reactive molecules

2020 ◽  
Vol 6 (51) ◽  
pp. eabd4699
Author(s):  
Mingyuan He ◽  
Chenwei Lv ◽  
Hai-Qing Lin ◽  
Qi Zhou
Keyword(s):  
Critical Role ◽  
Interaction Strength ◽  
Quantum Correlations ◽  
Polar Molecules ◽  
Many Body ◽  
Density Correlation ◽  
Ultracold Polar Molecules ◽  
Unexplored Area ◽  
Many Body Systems

The realization of ultracold polar molecules in laboratories has pushed physics and chemistry to new realms. In particular, these polar molecules offer scientists unprecedented opportunities to explore chemical reactions in the ultracold regime where quantum effects become profound. However, a key question about how two-body losses depend on quantum correlations in interacting many-body systems remains open so far. Here, we present a number of universal relations that directly connect two-body losses to other physical observables, including the momentum distribution and density correlation functions. These relations, which are valid for arbitrary microscopic parameters, such as the particle number, the temperature, and the interaction strength, unfold the critical role of contacts, a fundamental quantity of dilute quantum systems, in determining the reaction rate of quantum reactive molecules in a many-body environment. Our work opens the door to an unexplored area intertwining quantum chemistry; atomic, molecular, and optical physics; and condensed matter physics.

A RELATIVISTIC EFFECTIVE MODEL WITH PARAMETERIZED COUPLINGS FOR NEUTRON STARS: THE ROLE OF ANTIKAON CONDENSATES

2011 ◽  
Vol 20 (supp02) ◽  
pp. 133-139
Author(s):  
ALEXANDRE MESQUITA ◽  
MOISÉS RAZEIRA ◽  
DIMITER HADJIMICHEF ◽  
CÉSAR A. Z. VASCONCELLOS ◽  
ROSANA O. GOMES ◽  
...  
Keyword(s):  
Neutron Stars ◽  
Coupling Constants ◽  
Effective Model ◽  
Extended Model ◽  
Many Body ◽  
Parametric Dependence ◽  
Interaction Terms ◽  
Coupling Terms ◽  
Effective Models

We study the effects of antikaon condensates in neutron stars in the framework of a relativistic effective model with derivative couplings which includes genuine many-body forces simulated by nonlinear interaction terms involving scalar-isoscalar (σ, σ*), vector-isoscalar (ω, ɸ), vector-isovector (ϱ), scalar-isovector (δ) mesons. The effective model presented in this work has a philosophy quite similar to the original version of the model with parameterized couplings. But unlike that, in which the parametrization is directly inserted in the coupling constants of the Glendenning model, we present here a method for the derivation of the parametric dependence of the coupling terms, in a way that allows in one side to consistently justify this parametrization and in the other to extend in a coherent way the range of possibilities of parameterizations in effective models with derivative couplings. The extended model is then applied to the description of the mass of neutron stars.

On the Role of High-Order Multiple Scattering Terms in Br K-Edge XANES of the Ionic Conductor AgBr

1993 ◽  
Vol 176 (2) ◽  
pp. 503-510 ◽  
Author(s):  
A. V. Soldatov ◽  
T. S. Ivanchenko ◽  
S. Della Longa ◽  
A. Bianconi
Keyword(s):  
Multiple Scattering ◽  
High Order ◽  
Ionic Conductor

Characteristics in Response Integration and Bifurcation of a Forced Duffing Oscillator

2007 ◽  
Author(s):  
Jang-Der Jeng ◽  
Yuan Kang ◽  
Yeon-Pun Chang ◽  
Shyh-Shyong Shyr
Keyword(s):  
Applied Sciences ◽  
Phase Plane ◽  
Duffing Oscillator ◽  
High Order ◽  
Chaotic Motions ◽  
Integration Algorithm ◽  
High Order Harmonic ◽  
Stiffness And Damping

The Duffing oscillator is well-known models of nonlinear system, with applications in many fields of applied sciences and engineering. In this paper, a response integration algorithm is proposed to analyze high-order harmonic and chaotic motions in this oscillator for modeling rotor excitations. This method numerically integrates the distance between state trajectory and the origin in the phase plane during a specific period and predicted intervals with excitation periods. It provides a quantitative characterization of system responses and can replace the role of the traditional stroboscopic technique (Poincare´ section method) to observe bifurcations and chaos of the nonlinear oscillators. Due to the signal response contamination of system, thus it is difficult to identify the high-order responses of the subharmonic motion because of the sampling points on Poincare´ map too near each other. Even the system responses will be made misjudgments. Combining the capability of precisely identifying period and constructing bifurcation diagrams, the advantages of the proposed response integration method are shown by case studies. Applying this method, the effects of the change in the stiffness and the damping coefficients on the vibration features of a Duffing oscillator are investigated in this paper. From simulation results, it is concluded that the stiffness and damping of the system can effectively suppress chaotic vibration and reduce vibration amplitude.

scholarly journals Random k-Body Ensembles for Chaos and Thermalization in Isolated Systems

Entropy ◽  
2018 ◽  
Vol 20 (7) ◽  
pp. 541 ◽  
Author(s):  
Venkata Kota ◽  
Narendra Chavda
Keyword(s):  
Hermite Polynomials ◽  
Point Group ◽  
Majorana Fermions ◽  
Many Body ◽  
Boson Systems ◽  
Random Matrix Ensembles ◽  
Isolated Systems ◽  
Group Symmetries ◽  
Statistical Relaxation

Embedded ensembles or random matrix ensembles generated by k-body interactions acting in many-particle spaces are now well established to be paradigmatic models for many-body chaos and thermalization in isolated finite quantum (fermion or boson) systems. In this article, briefly discussed are (i) various embedded ensembles with Lie algebraic symmetries for fermion and boson systems and their extensions (for Majorana fermions, with point group symmetries etc.); (ii) results generated by these ensembles for various aspects of chaos, thermalization and statistical relaxation, including the role of q-hermite polynomials in k-body ensembles; and (iii) analyses of numerical and experimental data for level fluctuations for trapped boson systems and results for statistical relaxation and decoherence in these systems with close relations to results from embedded ensembles.

scholarly journals Role of high-order aberrations in senescent changes in spatial vision

2009 ◽  
Vol 9 (2) ◽  
pp. 24-24 ◽  
Author(s):  
S. L. Elliott ◽  
S. S. Choi ◽  
N. Doble ◽  
J. L. Hardy ◽  
J. W. Evans ◽  
...  
Keyword(s):  
Spatial Vision ◽  
High Order ◽  
High Order Aberrations

scholarly journals Three-nucleon forces

2014 ◽  
Vol 23 (09) ◽  
pp. 1430015 ◽  
Author(s):  
Peter U. Sauer
Keyword(s):  
Ab Initio Calculations ◽  
Ab Initio ◽  
Body Problem ◽  
Many Body ◽  
Nuclear Systems ◽  
The Difference

In this paper, the role of three-nucleon forces in ab initio calculations of nuclear systems is investigated. The difference between genuine and induced many-nucleon forces is emphasized. Induced forces arise in the process of solving the nuclear many-body problem as technical intermediaries toward calculationally converged results. Genuine forces make up the Hamiltonian. They represent the chosen underlying dynamics. The hierarchy of contributions arising from genuine two-, three- and many-nucleon forces is discussed. Signals for the need of the inclusion of genuine three-nucleon forces are studied in nuclear systems, technically best under control, especially in three-nucleon and four-nucleon systems. Genuine three-nucleon forces are important for details in the description of some observables. Their contributions to observables are small on the scale set by two-nucleon forces.

Elemental Interfaces and Displacive Phase Transformations

2008 ◽  
Vol 59 ◽  
pp. 63-68
Author(s):  
Václav Paidar
Keyword(s):  
Phase Transformations ◽  
Structural Changes ◽  
Atomic Plane ◽  
Many Body ◽  
Single Plane ◽  
Atomistic Models ◽  
Shear Type ◽  
Hcp Structure ◽  
The Many

Two basic processes, namely shear and shuffling of atomic planes can be considered as elementary mechanisms of displacive phase transformations. The atomistic models suitable to investigate the role of interfaces in the structural changes are tested. The many-body potentials are used for the description of interatomic forces. General displacements of atomic planes are examined, i.e. γ-surface type calculations extensively used for stacking fault and lattice dislocation analysis are applied to single plane shuffling and alternate shuffling of every other atomic plane producing in combination with homogeneous deformation the hcp structure. Similar approach considering shear type planar displacements leads to the Zener path between the bcc and fcc lattices. The effect of additional deformation required to obtain the close-packed atomic arrangements is analysed.

Role of the second nearest-neighbor hoppings in a disordered Bose–Hubbard Hamiltonian in the Many-Body Localization

2020 ◽  
Vol 93 (9) ◽  
Author(s):  
Edith Djoukouo Ngueyounou ◽  
Kanabet Yapara ◽  
Celsus Bouri ◽  
Hugues Merlain Tetchou Nganso ◽  
Moïse Godfroy Kwato Njock
Keyword(s):  
Nearest Neighbor ◽  
Many Body ◽  
Hubbard Hamiltonian ◽  
The Many
Sign in / Sign up

Export Citation Format

Share Document