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The concentration-mass relations proposed by Prada et al. (2012) and by Duffy et al. (2008) on the scales of galaxy clusters show some of the largest discrepancies among all the works present in literature. This is surprising because they…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-26 M. Meneghetti , E. Rasia

In this work, the transition between diffusion-limited and ballistic aggregation models was revisited using a model in which biased random walks simulate the particle trajectories. The bias is controlled by a parameter $\lambda$, which…

Statistical Mechanics · Physics 2009-11-11 S. C. Ferreira , S. G. Alves , A. Faissal Brito , J. G. Moreira

We present a new algorithm which allows for direct numerically exact solutions within dynamical mean-field theory (DMFT). It is based on the established Hirsch-Fye quantum Monte Carlo (HF-QMC) method. However, the DMFT impurity model is…

Strongly Correlated Electrons · Physics 2008-01-09 N. Blümer

A natural way to characterize the cluster structure of a dataset is by finding regions containing a high density of data. This can be done in a nonparametric way with a kernel density estimate, whose modes and hence clusters can be found…

Machine Learning · Computer Science 2015-03-03 Miguel Á. Carreira-Perpiñán

Dynamical mean field theory (DMFT) is a tool that allows to analyze the stochastic dynamics of $N$ interacting degrees of freedom in terms of a self-consistent $1$-body problem. In this work, focusing on models of ecosystems, we present the…

Disordered Systems and Neural Networks · Physics 2020-01-08 Felix Roy , Giulio Biroli , Guy Bunin , Chiara Cammarota

We present an embedding scheme for periodic systems that facilitates the treatment of the physically important part (here the unit cell) with advanced electronic-structure methods, that are computationally too expensive for periodic…

Materials Science · Physics 2016-04-08 Wael Chibani , Xinguo Ren , Matthias Scheffler , Patrick Rinke

The dynamical susceptibility of strongly correlated electronic systems can be calculated within the framework of the dynamical mean-field theory (DMFT). The required measurement of the four-point vertex of the auxiliary impurity model is…

Strongly Correlated Electrons · Physics 2019-06-06 Friedrich Krien

The diagramatic Monte Carlo method has so far been primarily used in connection with the weak coupling expansion. Here we show that the strong coupling expansion offers a significant advantage: it can be efficiently implemented on both the…

Strongly Correlated Electrons · Physics 2023-11-17 Kristjan Haule

We propose a numerical technique based on a combination of short-iterative Lanczos and exact diagonalization methods, suitable for simulating the time evolution of the reduced density matrix of a single qubit interacting with an…

We develop a method for calculating the self-energy of a quantum impurity coupled to a continuous bath by stochastically generating a distribution of finite Anderson models that are solved by exact diagonalization, using the noninteracting…

Strongly Correlated Electrons · Physics 2012-09-13 Mats Granath , Hugo U. R. Strand

While the traditional local-density approximation (LDA) cannot describe Mott insulators, {\it ab-initio} determination of the Hubbard $U$, for example, limits LDA-plus dynamical mean field theory (DMFT) approaches. Here, we attempt to…

Strongly Correlated Electrons · Physics 2009-02-12 M. S. Laad , L. Hozoi , L. Craco

Decoherence of a center spin or qubit in a spin bath is essentially determined by the many-body bath evolution. We develop a cluster-correlation expansion (CCE) theory for the spin bath dynamics relevant to the qubit decoherence problem. A…

Mesoscale and Nanoscale Physics · Physics 2008-08-25 Wen Yang , Ren-bao Liu

We implement an efficient numerical method to calculate response functions of complex impurities based on the Density Matrix Renormalization Group (DMRG) and use it as the impurity-solver of the Dynamical Mean Field Theory (DMFT). This…

Strongly Correlated Electrons · Physics 2017-11-27 Y. Núñez Fernández , K. Hallberg

Quantum embedding approaches involve the self-consistent optimization of a local fragment of a strongly correlated system, entangled with the wider environment. The `energy-weighted' density matrix embedding theory (EwDMET) was established…

Strongly Correlated Electrons · Physics 2021-02-23 P. V. Sriluckshmy , Max Nusspickel , Edoardo Fertitta , George H. Booth

Standard density functional approximations often give questionable results for odd-electron radical complexes, with the error typically attributed to self-interaction. In density corrected density functional theory (DC-DFT), certain classes…

Chemical Physics · Physics 2015-06-19 Min-Cheol Kim , Eunji Sim , Kieron Burke

The solution of a generalized impurity model lies at the heart of electronic structure calculations with dynamical mean-field theory (DMFT). In the strongly-correlated regime, the method of choice for solving the impurity model is the…

Strongly Correlated Electrons · Physics 2014-09-23 P. Sémon , Chuck-Hou Yee , Kristjan Haule , A. -M. S. Tremblay

We discuss a generalization of the dynamical mean field theory (DMFT) for strongly correlated systems close to a Mott transition based on a systematic approximation of the fully irreducible four-point vertex. It is an atomic-limit…

Strongly Correlated Electrons · Physics 2016-09-07 Thomas Ayral , Olivier Parcollet

Finding the number of meaningful clusters in an unlabeled dataset is important in many applications. Regularized k-means algorithm is a possible approach frequently used to find the correct number of distinct clusters in datasets. The most…

Machine Learning · Computer Science 2025-05-30 Behzad Kamgar-Parsi , Behrooz Kamgar-Parsi

Finite-Hamiltonian impurity solvers provide direct real-frequency spectra and a natural route to enlarged impurity Hamiltonians, but their applicability is limited by the rapid Hilbert-space growth with the number of bath or other added…

Strongly Correlated Electrons · Physics 2026-05-11 Jeongmoo Lee , Ara Go

In a recent paper [M. G\"ul et al., Phys. Rev. E, 110 (6), 064115] we showed that test particle sum rules, which address the excess chemical potential and isothermal compressibility, could be used to develop new and accurate classical…

Soft Condensed Matter · Physics 2026-04-09 Melih Gül , Roland Roth , Robert Evans