Article
Chemistry, Physical
Onur Caylak, Bjorn Baumeier
Summary: The study focuses on gas-phase geometry optimization of molecules in excited states using many-body Green's functions theory within the GW approximation and the Bethe-Salpeter equation. The results show good agreement with higher-order wave function methods for structural parameters, indicating the efficiency of the GW-BSE method in providing accurate excitation energies and geometries.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2021)
Article
Computer Science, Interdisciplinary Applications
Andy T. S. Wan, Alexander Bihlo, Jean-Christophe Nave
Summary: Conservative symmetric second-order one-step schemes are derived using the Discrete Multiplier Method for describing dynamical systems of various many-body systems. These schemes are applicable to a wide range of many-body problems in biology, chemistry, fluid mechanics, and physics, and have been verified through numerical experiments.
JOURNAL OF COMPUTATIONAL PHYSICS
(2022)
Review
Physics, Multidisciplinary
M. Ridley, N. W. Talarico, D. Karlsson, N. Lo Gullo, R. Tuovinen
Summary: The non-equilibrium Green's function (NEGF) formalism is one of the most versatile theoretical approaches to studying time-dependent correlated quantum transport in nano-systems, capable of treating inter-particle interactions, external drives and/or perturbations, and coupling to baths with a (piece-wise) continuum set of degrees of freedom.
JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL
(2022)
Article
Mathematics, Applied
G. Quee, R. Edwards
Summary: The study explores the use of ramp functions as an alternative approximation to the sigmoid in networks of regulatory interactions of biological molecules, restoring continuity to the vector field and removing the assumption of infinitely steep switching. A general framework for describing a ramp system using the 'focal points' of the corresponding Glass network is provided, along with exploring solutions of two-dimensional and higher-dimensional networks under certain restrictions, as well as periodic behavior and the existence of periodic solutions in negative feedback loops.
PHYSICA D-NONLINEAR PHENOMENA
(2021)
Article
Chemistry, Physical
Ru-song Li, Jin-tao Wang, Fei Wang, Zhi-yong Liu, Yuan-ming Wang, Ze-lin Cao, Zheng Xie
Summary: The electronic properties of curium trichloride (CmCl3) were studied using single-particle approximations and a many-body approach. The results suggest that CmCl3 is in the orbital-selective localized state, with weak electron hybridization and localized conducting state. The quasiparticle band structure was also predicted.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Vibin Abraham, Nicholas J. Mayhall
Summary: Size extensivity is an important property for many-body methods, but traditional configuration interaction (CI) methods lack this property. Coupled electron pair approximation (CEPA) methods can ensure size extensivity, but they face singularity issues. In this study, we extend the CEPA methods to a new formulation based on tensor product states (TPS) and demonstrate their application in various systems. The results show that the TPS-CEPA method can eliminate singularities and provide improved numerical results.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2022)
Article
Management
Kristof Berczi, Matthias Mnich, Roland Vincze
Summary: The multiple traveling salesman problem (mTSP) is a variant of the classical traveling salesman problem where a set of m salesmen visit all cities from a set of n cities. The mTSP has various real-life applications, especially in vehicle routing problems. This work introduces the many-visits mTSP, which extends the mTSP by specifying a visitation frequency for each city and presents polynomial-time algorithms to solve this problem.
OMEGA-INTERNATIONAL JOURNAL OF MANAGEMENT SCIENCE
(2023)
Article
Mathematics, Applied
Skye Dore-Hall, Roderick Edwards
Summary: In a model of plant phenylalanine metabolism, two mechanisms prioritize primary metabolism over secondary metabolism when synthesis rates of shikimate are low: the Precursor Shutoff Valve (PSV) and threshold separation. The Shikimate Ester Loop (SEL) is effective in prioritizing primary metabolism, and the threshold constant of the secondary pathway determines this prioritization.
PHYSICA D-NONLINEAR PHENOMENA
(2022)
Article
Physics, Multidisciplinary
M. J. Hyrkas, D. Karlsson, R. van Leeuwen
Summary: This paper presents an improved diagrammatic approximation method to preserve the positivity of observables at finite temperature. By using cutting rules, it solves the problem of negative spectral densities and non-vanishing vacuum diagrams, and also derives an analytic continuation relation between retarded N-point functions and their Matsubara counterparts.
JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL
(2022)
Article
Mathematics, Applied
Wenzhong Zhang, Bo Wang, Wei Cai
Summary: A matrix basis formulation is introduced to represent the 3 x 3 frequency domain dyadic Green's functions of Maxwell's equations in 3-dimensional layered media. The formulation allows for the decomposition of Maxwell's Green's functions into independent TE and TM components, each satisfying a scalar Helmholtz equation. Moreover, it simplifies the interface transmission conditions for the electromagnetic fields.
SIAM JOURNAL ON APPLIED MATHEMATICS
(2022)
Article
Astronomy & Astrophysics
Massimiliano Maria Riva, Filippo Vernizzi, Leong Khim Wong
Summary: This paper presents a novel calculation method for accurately calculating the momentum radiated into gravitational waves during the scattering of two spinning bodies. The result is derived using a Routhian-based worldline effective field theory formalism and a battery of analytic techniques for evaluating loop integrals. The authors show that the inclusion of spins allows for momentum loss in all three spatial directions, which is verified by comparing the expression for radiated energy with state-of-the-art calculations in post-Newtonian theory.
Article
Computer Science, Interdisciplinary Applications
Nail A. Gumerov, Ramani Duraiswami
Summary: The paper introduces and studies the Green's functions for the Laplace equation on an infinite plane with a circular hole satisfying the Dirichlet and Neumann boundary conditions. These functions enable solutions to boundary value problems in domains with locally rough surfaces, considering arbitrary positive and negative ground elevations. Integral and series representations of the Green's functions are provided, and an efficient computational technique based on the boundary element method with fast multipole acceleration is developed, with numerical studies of benchmark problems presented.
JOURNAL OF COMPUTATIONAL PHYSICS
(2021)
Article
Operations Research & Management Science
Steven Duda, Edeltraud Gehrig, Thomas Lorenz
Summary: In this paper, we discuss the problem of focusing on reachable sets instead of single state vectors in control systems with uncertainty and imprecision. We propose a method of approximating the solutions by intersections of finitely many time-dependent ellipsoids characterized by solutions to a system of ordinary differential equations.
JOURNAL OF OPTIMIZATION THEORY AND APPLICATIONS
(2022)
Article
Physics, Multidisciplinary
S. Flannigan, F. Damanet, A. J. Daley
Summary: In this Letter, the authors propose a method that combines nonMarkovian quantum state diffusion techniques with tensor network methods to capture the non-Markovian dynamics of open quantum systems. By applying this method to a Hubbard-Holstein model, they are able to quantitatively assess the impact of non-Markovian dissipation on correlation spreading and find that these effects can enhance correlation growth, providing new routes for dissipatively enhancing transport and correlation spreading in both solid state and cold atom experiments.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Multidisciplinary
Ze-Pei Cian, Hossein Dehghani, Andreas Elben, Benoit Vermersch, Guanyu Zhu, Maissam Barkeshli, Peter Zoller, Mohammad Hafezi
Summary: The proposed experimental scheme in this study allows for the measurement of the many-body Chern number without the need for ancilla or knowledge of the Hamiltonian. By utilizing statistical correlations of randomized measurements, the MBCN of a wave function can be inferred, particularly in disklike geometries that are more suitable for current quantum simulator architectures.
PHYSICAL REVIEW LETTERS
(2021)
Article
Chemistry, Physical
Nathaniel Raimbault, Paul L. de Boeij, Pina Romaniello, J. A. Berger
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2016)
Article
Physics, Condensed Matter
R. Ferradas, J. A. Berger, Pina Romaniello
EUROPEAN PHYSICAL JOURNAL B
(2018)
Article
Chemistry, Physical
Pierre-Francois Loos, Pina Romaniello, J. A. Berger
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2018)
Article
Physics, Condensed Matter
Walter Tarantino, Bernardo S. Mendoza, Pina Romaniello, J. A. Berger, Lucia Reining
JOURNAL OF PHYSICS-CONDENSED MATTER
(2018)
Article
Chemistry, Physical
Mickael Veril, Pina Romaniello, J. A. Berger, Pierre-Francois Loos
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2018)
Article
Chemistry, Physical
S. Di Sabatino, J. A. Berger, P. Romaniello
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2019)
Article
Chemistry, Physical
J. Arjan Berger, Pierre-Francois Loos, Pina Romaniello
Summary: This study demonstrates the advantages of using the COHSEX approach in calculating potential energy surfaces, showing smoother results compared to other methods. The use of self-consistent COHSEX QP energies and orbitals can lead to results independent of the starting point and improved equilibrium distances. The total energies may worsen with self-consistency, but the equilibrium distances are improved due to changes in screening within the Bethe-Salpeter equation.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2021)
Article
Chemistry, Multidisciplinary
S. Di Sabatino, P. -F. Loos, P. Romaniello
Summary: In this study, with the simple Hubbard dimer, it was found that the issue of multiple quasiparticle solutions in the one-shot GW method can be resolved by full self-consistency. The Bethe-Salpeter equation formalism was used to analyze the neutral excitation spectrum within the standard GW approximation, revealing the impact of factors such as increasing electron-electron interaction on the excitation energies. The trace formula was shown to exhibit correct behavior for weak interactions, while the ACFDT expression was more stable but less accurate, highlighting the different characteristics of each approach in predicting correlation energies.
FRONTIERS IN CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
S. Di Sabatino, J. Koskelo, J. Prodhon, J. A. Berger, M. Caffarel, P. Romaniello
Summary: The Extended Koopman's Theorem (EKT) and Many-body Effective Energy Theory (MEET) are connected and can benefit from each other. By solving the secular equation of EKT, a more optimal basis set for MEET can be chosen. The findings are illustrated with examples of the Hubbard dimer and bulk silicon.
FRONTIERS IN CHEMISTRY
(2021)
Article
Chemistry, Physical
Stefano Di Sabatino, Claudio Verdozzi, Pina Romaniello
Summary: The study explores the evolution of the one-body density matrix in out-of-equilibrium systems, particularly focusing on the challenges posed by strong electron correlations. Using the two-site Anderson impurity model as a case study and an adiabatic approximation based on the exact ground-state two-body density matrix, the research reveals various difficulties and obstacles in accurately describing the system dynamics.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
S. Di Sabatino, J. A. Berger, P. Romaniello
FARADAY DISCUSSIONS
(2020)
Article
Materials Science, Multidisciplinary
Sarah Cavo, J. A. Berger, Pina Romaniello
Article
Materials Science, Multidisciplinary
Walter Tarantino, Pina Romaniello, J. A. Berger, Lucia Reining
Article
Materials Science, Multidisciplinary
Davide Sangalli, J. A. Berger, Claudio Attaccalite, Myrta Gruning, Pina Romaniello
Article
Materials Science, Multidisciplinary
Stefano Di Sabatino, J. A. Berger, Lucia Reining, Pina Romaniello