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We study the Hubbard model at half band-filling on a Bethe lattice with infinite coordination number in the paramagnetic insulating phase at zero temperature. We use the dynamical mean-field theory (DMFT) mapping to a single-impurity…

Strongly Correlated Electrons · Physics 2009-11-10 Satoshi Nishimoto , Florian Gebhard , Eric Jeckelmann

We solve the nonequilibrium dynamical mean-field theory (DMFT) using matrix product states (MPS). This allows us to treat much larger bath sizes and by that reach substantially longer times (factor $\sim$ 2 -- 3) than with exact…

Strongly Correlated Electrons · Physics 2014-12-22 F. Alexander Wolf , Ian P. McCulloch , Ulrich Schollwöck

The electron-phonon ($e$-ph) coupling system often has a large number of phonon degrees of freedom, whose spectral functions are numerically difficult to compute using matrix product state (MPS) formalisms. To solve this problem, we propose…

Strongly Correlated Electrons · Physics 2023-04-19 Pei-Yuan Zhao , Ke Ding , Shuo Yang

In order to study electron-transfer mediated chemical processes on a metal surface, one requires not one but two potential energy surfaces (one ground state and one excited state) as in Marcus theory. In this letter, we report that a novel,…

Chemical Physics · Physics 2023-03-22 Junhan Chen , Joseph Subotnik

Using an Environmentally Friendly Renormalization we derive, from an underlying field theory representation, a formal expression for the equation of state, $y=f(x)$, that exhibits all desired asymptotic and analyticity properties in the…

Statistical Mechanics · Physics 2008-11-26 D. J. O'Connor , J. A. Santiago , C. R. Stephens

Simplicial complexes (SCs) have become a popular abstraction for analyzing complex data using tools from topological data analysis or topological signal processing. However, the analysis of many real-world datasets often leads to dense SCs,…

Machine Learning · Statistics 2025-10-07 Anton Savostianov , Michael T. Schaub , Nicola Guglielmi , Francesco Tudisco

Field theoretical renormalization group methods are applied to a simple model of a passive scalar quantity advected by the Gaussian non-solenoidal (``compressible'') velocity field with the covariance $\propto\delta(t-t')|…

chao-dyn · Physics 2009-10-31 Loran Ts. Adzhemyan , Nikolaj V. Antonov

Gradient matching with Gaussian processes is a promising tool for learning parameters of ordinary differential equations (ODE's). The essence of gradient matching is to model the prior over state variables as a Gaussian process which…

Machine Learning · Statistics 2016-10-25 Nico S. Gorbach , Stefan Bauer , Joachim M. Buhmann

The convergence property of a stochastic algorithm for the self-consistent field (SCF) calculations of electron structures is studied. The algorithm is formulated by rewriting the electron charges as a trace/diagonal of a matrix function,…

Numerical Analysis · Mathematics 2023-04-20 Taehee Ko , Xiantao Li

Excited-state molecular dynamics (ESMD) simulations near conical intersections (CIs) pose significant challenges when using machine learning potentials (MLPs). Although MLPs have gained recognition for their integration into mixed…

Chemical Physics · Physics 2025-01-17 Sung Wook Moon , Soohaeng Yoo Willow , Tae Hyeon Park , Seung Kyu Min , Chang Woo Myung

We analyze in a closed form the learning dynamics of stochastic gradient descent (SGD) for a single-layer neural network classifying a high-dimensional Gaussian mixture where each cluster is assigned one of two labels. This problem provides…

Machine Learning · Computer Science 2022-03-28 Francesca Mignacco , Florent Krzakala , Pierfrancesco Urbani , Lenka Zdeborová

During the past 15 years, the density matrix renormalization group (DMRG) has become increasingly important for ab initio quantum chemistry. Its underlying wavefunction ansatz, the matrix product state (MPS), is a low-rank decomposition of…

Chemical Physics · Physics 2014-09-25 Sebastian Wouters , Dimitri Van Neck

Chemotaxis models describe the movement of organisms in response to chemical gradients. In this paper, we present a stochastic interacting particle-field algorithm with a random batch approximation (SIPF-$r$) for the three-dimensional (3D)…

Numerical Analysis · Mathematics 2026-01-26 Boyi Hu , Zhongjian Wang , Jack Xin , Zhiwen Zhang

The standard approach to analyzing brain electrical activity is to examine the spectral density function (SDF) and identify predefined frequency bands that have the most substantial relative contributions to the overall variance of the…

We propose a simple variational wave function that captures the correct ground state energy of the spin-1 Heisenberg chain model to within 0.04\%. The wave function is written in the matrix product state (MPS) form with the bond dimension…

Strongly Correlated Electrons · Physics 2020-08-19 Jintae Kim , Minsoo Kim , Naoki Kawashima , Jung Hoon Han , Hyun-Yong Lee

Accurate simulation of the non-adiabatic dynamics of molecules in excited electronic states is key to understanding molecular photo-physical processes. Here we present a novel method, based on a semiclassical approximation, that is as…

Chemical Physics · Physics 2016-05-24 Alexander White , Sergei Tretiak , Dmitry Mozyrsky

We present the numerical implementation of the time-dependent complete-active-space self-consistent-field (TD-CASSCF) method [Phys. Rev. A, 88, 023402 (2013)] for atoms driven by a strong linearly polarized laser pulse. The present…

Self-consistent field theory (SCFT) is one of the most widely-used framework in studying the equilibrium phase behaviors of inhomogenous polymers. For liquid crystalline polymeric systems, the main numerical challenges of solving SCFT…

Numerical Analysis · Mathematics 2024-09-16 Zhijuan He , Kai Jiang , Liwei Tan , Xin Wang

A momentum-space approach of the density-matrix renormalization-group (DMRG) method is developed. Ground state energies of the Hubbard model are evaluated using this method and compared with exact diagonalization as well as quantum…

Condensed Matter · Physics 2009-10-28 T. Xiang

We present a new second order complete active space self-consistent field implementation to converge wavefunctions for both large active spaces and large atomic orbital (AO) bases. Our algorithm decouples the active space wavefunction…

Chemical Physics · Physics 2017-08-23 Qiming Sun , Jun Yang , Garnet Kin-Lic Chan