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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

Affinity propagation clustering (AP) has two limitations: it is hard to know what value of parameter 'preference' can yield an optimal clustering solution, and oscillations cannot be eliminated automatically if occur. The adaptive AP method…

Artificial Intelligence · Computer Science 2008-05-09 Kaijun Wang , Junying Zhang , Dan Li , Xinna Zhang , Tao Guo

A new cluster analysis method, $K$-quantiles clustering, is introduced. $K$-quantiles clustering can be computed by a simple greedy algorithm in the style of the classical Lloyd's algorithm for $K$-means. It can be applied to large and…

Methodology · Statistics 2019-11-12 Christian Hennig , Cinzia Viroli , Laura Anderlucci

We derive coupled-cluster equations for three-body Hamiltonians. The equations for the one- and two-body cluster amplitudes are presented in a factorized form that leads to an efficient numerical implementation. We employ low-momentum two-…

Nuclear Theory · Physics 2008-11-26 G. Hagen , T. Papenbrock , D. J. Dean , A. Schwenk , A. Nogga , M. Wloch , P. Piecuch

We present excitation energies for molecular doublets from a spin-adapted formulation of coupled cluster singles and doubles theory. The entanglement coupled cluster approach represents an unconventional take on the notorious problem of…

Chemical Physics · Physics 2025-04-08 Sarai Dery Folkestad , Kristine Lauvstad Kruken , Henrik Koch

The dynamics of quantum systems can be approximated by the time propagation of Gaussian wave packets. Applying a time dependent variational principle, the time evolution of the parameters of the coupled Gaussian wave packets can be…

Quantum Physics · Physics 2008-02-01 T. Fabcic , J. Main , G. Wunner

In this paper, we present a cluster algorithm for the simulation of hard spheres and related systems. In this algorithm, a copy of the configuration is rotated with respect to a randomly chosen pivot point. The two systems are then…

Statistical Mechanics · Physics 2008-02-03 Christophe Dress , Werner Krauth

Model-based clustering is a powerful tool that is often used to discover hidden structure in data by grouping observational units that exhibit similar response values. Recently, clustering methods have been developed that permit…

Methodology · Statistics 2025-06-24 Sally Paganin , Garritt L. Page , Fernando Andrés Quintana

Cooling methods and particle slowers as well as accelerators are basic tools for fundamental research and applications in different fields and systems. We put forward a generic mechanism to scale the momentum of a particle, regardless of…

Quantum Physics · Physics 2020-11-04 J. G. Muga , S. Martínez-Garaot , M. Pons , M. Palmero , A. Tobalina

Numerical studies are presented to assess error estimates for a separable (Hartree) approximation for dynamically evolving composite quantum systems which exhibit distinct scales defined by their mass and frequency ratios. The relevant…

Clustering methods seek to partition data such that elements are more similar to elements in the same cluster than to elements in different clusters. The main challenge in this task is the lack of a unified definition of a cluster,…

Statistics Theory · Mathematics 2022-07-06 Franz Besold , Vladimir Spokoiny

Coupled cluster and symmetry projected Hartree-Fock are two central paradigms in electronic structure theory. However, they are very different. Single reference coupled cluster is highly successful for treating weakly correlated systems,…

We are interested in clustering parts of a given single multi-variate series in an unsupervised manner. We would like to segment and cluster the series such that the resulting blocks present in each cluster are coherent with respect to a…

Process discovery algorithms automatically extract process models from event logs, but high variability often results in complex and hard-to-understand models. To mitigate this issue, trace clustering techniques group process executions…

Machine Learning · Computer Science 2025-12-11 Jari Peeperkorn , Johannes De Smedt , Jochen De Weerdt

A time-dependent multiconfigurational self-consistent field theory is presented to describe the many-body dynamics of a gas of identical bosonic atoms confined to an external trapping potential at zero temperature from first principles. A…

Other Condensed Matter · Physics 2007-10-16 David J. Masiello , William P. Reinhardt

Recently developed pair coupled cluster doubles (pCCD) theory successfully reproduces doubly occupied configuration interaction (DOCI) with mean field cost. However, the projective nature of pCCD makes the method non-variational and thus…

Chemical Physics · Physics 2016-08-19 Luning Zhao , Eric Neuscamman

The paper outlines an exact combinatorial approach to finite coagulating systems. In this approach, cluster sizes and time are discrete, and the binary aggregation alone governs the time evolution of the systems. By considering the growth…

Statistical Mechanics · Physics 2018-02-21 Agata Fronczak , Anna Chmiel , Piotr Fronczak

This paper proposes a composite adaptive control architecture using dual adaptation scheme for dynamical systems comprising time-varying uncertain parameters. While majority of the adaptive control schemes in literature address the case of…

Systems and Control · Electrical Eng. & Systems 2022-06-06 Raghavv Goel , Sayan Basu Roy

The nuclear time-dependent density functional theory (TDDFT) is a tool of choice for describing various dynamical phenomena in atomic nuclei. In a recent study, we reported an extension of the framework - the multiconfigurational TDDFT…

Nuclear Theory · Physics 2024-01-24 Petar Marević , David Regnier , Denis Lacroix

We demonstrate a simple method by which time-dependent interactions can be exploited to improve self-assembly in colloidal systems. We apply this method to two systems: a model colloid with short-ranged attractive potentials that undergoes…

Soft Condensed Matter · Physics 2017-09-13 Christopher J. Fullerton , Robert L. Jack