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Related papers: Comparison of two quantum-cluster approximations

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A synchronization mechanism driven by annealed noise is studied for two replicas of a coupled-map lattice which exhibits stable chaos (SC), i.e. irregular behavior despite a negative Lyapunov spectrum. We show that the observed…

Statistical Mechanics · Physics 2007-05-23 F. Bagnoli , F. Cecconi

We present new results for LambdaCC and MotifCC, two recently introduced variants of the well-studied correlation clustering problem. Both variants are motivated by applications to network analysis and community detection, and have…

Computational Complexity · Computer Science 2018-09-26 David F. Gleich , Nate Veldt , Anthony Wirth

In this paper we study from a numerical analysis perspective the Fractional Step Kinetic Monte Carlo (FS-KMC) algorithms proposed in [1] for the parallel simulation of spatially distributed particle systems on a lattice. FS-KMC are…

Numerical Analysis · Mathematics 2012-08-07 Giorgos Arampatzis , Markos A. Katsoulakis , Petr Plechac

We report developments of the kinetic Monte Carlo (KMC) method with improved accuracy and increased versatility for the description of atomic diffusivity on metal surfaces. The on-lattice constraint built into our recently proposed…

Materials Science · Physics 2008-11-27 Oleg Trushin , Handan Yildirim , Abdelkader Kara , Talat S. Rahman

A Dyson map explicitly determines the appropriate basis of electromagnetic fields which yields a unitary representation of the Maxwell equations in an inhomogeneous medium. A qubit lattice algorithm (QLA) is then developed perturbatively to…

While limited coupled cluster theory is \textit{formally} nonvariational, it is not broadly appreciated whether this is a major issue \textit{in practice}. We carried out a detailed comparison with \textit{de facto} full CI energies for a…

Chemical Physics · Physics 2024-10-03 Jan M. L. Martin , Emmanouil Semidalas

We present an analytical proof and numerical demonstrations of the equivalence of the correlation energy from particle-particle random phase approximation (pp-RPA) and ladder-couple-cluster-doubles (ladder-CCD). These two theories reduce to…

Chemical Physics · Physics 2013-11-01 Degao Peng , Stephan N. Steinmann , Helen van Aggelen , Weitao Yang

Centered kernel alignment (CKA) is a popular metric for comparing representations, determining equivalence of networks, and neuroscience research. However, CKA does not account for the underlying manifold and relies on numerous heuristics…

Machine Learning · Computer Science 2025-10-28 Mohammad Tariqul Islam , Du Liu , Deblina Sarkar

The structure of the QCD gluonic cascade in configuration space is investigated. The explicit form of the inclusive single particle density in configuration space transverse coordinates is derived in the double logarithmic approximation…

High Energy Physics - Phenomenology · Physics 2007-05-23 B. Ziaja

The M$_k$ models for 1D lattice fermions are characterised by ${\cal N}=2$ supersymmetry and by an order-$k$ clustering property. This paper highlights connections with quantum field theories (QFTs) in various regimes. At criticality the…

Statistical Mechanics · Physics 2017-07-19 T. Fokkema , K. Schoutens

We benchmark the ground state energies and the density profiles of atomic repulsive Fermi gases in optical lattices computed via Density Functional Theory (DFT) against the results of diffusion Monte Carlo (DMC) simulations. The main focus…

Quantum Gases · Physics 2018-06-12 S. Pilati , I. Zintchenko , M. Troyer , F. Ancilotto

Linearized Coupled Cluster Doubles (LinCCD) often provides near-singular energies in small-gap systems that exhibit static correlation. This has been attributed to the lack of quadratic $T_2^2$ terms that typically balance out small energy…

Chemical Physics · Physics 2025-05-13 Kevin Carter-Fenk

The mean spherical approximation (MSA) is a closure relation for pair correlation functions (two-point functions) in statistical physics. It can be applied to a wide range of systems, is computationally fairly inexpensive, and when properly…

High Energy Physics - Theory · Physics 2016-11-07 Arturo Amador , Johan Skule Høye , Kåre Olaussen

Finding the ground state of Ising spin glasses is notoriously difficult due to disorder and frustration. Often, this challenge is framed as a combinatorial optimization problem, for which a common strategy employs simulated annealing, a…

Relations between categorical variables can be analyzed conveniently by multiple correspondence analysis (MCA). %It is well suited to discover relations that may exist between categories of different variables. The graphical representation…

Methodology · Statistics 2016-03-11 Patrick J. F. Groenen , Julie Josse

Diffusion-Limited Aggregation (DLA) is a cluster-growth model that consists in a set of particles that are sequentially aggregated over a two-dimensional grid. In this paper, we introduce a biased version of the DLA model, in which…

Discrete Mathematics · Computer Science 2021-12-20 Nicolas Bitar , Eric Goles , Pedro Montealegre

We propose a modified coupled cluster Monte Carlo algorithm that stochastically samples connected terms within the truncated Baker--Campbell--Hausdorff expansion of the similarity transformed Hamiltonian by construction of coupled cluster…

Chemical Physics · Physics 2019-06-19 Charles J. C. Scott , Roberto Di Remigio , T. Daniel Crawford , Alex J. W. Thom

We present a detailed discussion of our novel diagrammatic coupled cluster Monte Carlo (diagCCMC) [Scott et al. J. Phys. Chem. Lett. 2019, 10, 925]. The diagCCMC algorithm performs an imaginary-time propagation of the similarity-transformed…

Chemical Physics · Physics 2020-10-28 Charles J. C. Scott , Roberto Di Remigio , T. Daniel Crawford , Alex J. W. Thom

A new method that accurately describes strongly correlated states and captures dynamical correlation is presented. It is derived as a modification of coupled-cluster theory with single and double excitations (CCSD) through consideration of…

Chemical Physics · Physics 2013-07-15 Daniel Kats , Frederick R. Manby

One-dimensional quantum cellular automata (QCA) consist in a line of identical, finite dimensional quantum systems. These evolve in discrete time steps according to a local, shift-invariant unitary evolution. By local we mean that no…

Quantum Physics · Physics 2008-04-15 Pablo Arrighi , Vincent Nesme , Reinhard Werner