English
Related papers

Related papers: Simple regularization scheme for multi-reference d…

200 papers

In this paper, the solution to the empirical risk minimization problem with $f$-divergence regularization (ERM-$f$DR) is presented and conditions under which the solution also serves as the solution to the minimization of the expected…

Machine Learning · Statistics 2026-01-21 Francisco Daunas , Iñaki Esnaola , Samir M. Perlaza , H. Vincent Poor

Many-body perturbation theory (MBPT) based on Green's functions and Feynman diagrams provides a fundamental theoretical framework for various \emph{ab initio} computational approaches in molecular and materials science, including the random…

Quantum Physics · Physics 2025-03-20 Yuqi Wang , Wei-Hai Fang , Zhendong Li

A detailed account of the implementation of equations of the Relativistic Density Functional Theory (RDFT) using basis sets of APW/LAPW type with flexible extensions provided by local orbitals is given. Earlier discoveries of the importance…

Materials Science · Physics 2021-04-07 Andrey L. Kutepov

In this paper, we apply the recently developed ab initio renormalized excitonic method (REM) to the excitation energy calculations of various molecular aggregates, through the extension of REM to the time-dependent density functional theory…

Chemical Physics · Physics 2013-05-07 Yingjin Ma , Haibo Ma

We review current methods for building PSF-matching kernels for the purposes of image subtraction or coaddition. Such methods use a linear decomposition of the kernel on a series of basis functions. The correct choice of these basis…

Instrumentation and Methods for Astrophysics · Physics 2015-06-04 A. C. Becker , D. Homrighausen , A. J. Connolly , C. R. Genovese , R. Owen , S. J. Bickerton , R. H. Lupton

Density functional theory is a preferred microscopic method for calculation of nuclear properties over the whole nuclear chart. Besides ground-state properties, which are calculated by Hartree-Fock theory, nuclear excitations can be…

Nuclear Theory · Physics 2020-06-02 Anton Repko

The exchange part of energy density of the linear Dirac--Hartree--Fock (DHF) model in symmetric nuclear matter is evaluated in a parameter--free closed form and expressed as density functional. After the rearranging terms the relativistic…

Nuclear Theory · Physics 2021-04-27 S. Gmuca , K. Petrik , J. Leja

Reduced density-matrix functional theory (RDMFT) is a promising alternative approach to the problem of electron correlation. Like standard density functional theory, it contains an unknown exchange-correlation functional, for which several…

Chemical Physics · Physics 2017-03-03 N. N. Lathiotakis , Miguel A. L. Marques

Energy density functionals (EDFs) have been used extensively with great success to calculate properties of nuclei and to predict the equation of state (EOS) of dense nuclear matter. Besides non-relativistic EDFs, mostly of the Skyrme or…

Nuclear Theory · Physics 2024-10-29 Stefan Typel , Shalom Shlomo

The solution to empirical risk minimization with $f$-divergence regularization (ERM-$f$DR) is extended to constrained optimization problems, establishing conditions for equivalence between the solution and constraints. A dual formulation of…

Machine Learning · Statistics 2025-02-21 Francisco Daunas , Iñaki Esnaola , Samir M. Perlaza , Gholamali Aminian

Inverse problems are fundamental in fields like medical imaging, geophysics, and computerized tomography, aiming to recover unknown quantities from observed data. However, these problems often lack stability due to noise and…

Numerical Analysis · Mathematics 2024-06-26 Andrea Ebner , Matthias Schwab , Markus Haltmeier

Broadly speaking, the calculation of core spectra such as electron energy loss spectra (EELS) at the level of density functional theory (DFT) usually relies one of two approaches: conceptually more complex but computationally efficient…

We present fully empirical exchange-correlation functionals to be used within reduced density matrix functional theory (RDMFT). These are of the popular J-K form, where the function of the occupation numbers that multiplies the Fock orbital…

Computational Physics · Physics 2017-03-03 Miguel A. L. Marques , N. N. Lathiotakis

In nuclear physics, Density Functional Theory (DFT) provides the basis for state-of-the art studies of ground-state properties of heavy nuclei. However, the direct relation of the density functional underlying these calculations and the…

Nuclear Theory · Physics 2016-12-21 Sandra Kemler , Martin Pospiech , Jens Braun

We propose a hybrid approach which employs the dynamical mean-field theory (DMFT) self-energy for the correlated, typically rather localized orbitals and a conventional density functional theory (DFT) exchange-correlation potential for the…

Strongly Correlated Electrons · Physics 2021-06-16 Sumanta Bhandary , Karsten Held

This investigation is motivated by PDE-constrained optimization problems arising in connection with electrocardiograms (ECGs) and electroencephalography (EEG). Standard sparsity regularization does not necessarily produce adequate results…

Numerical Analysis · Mathematics 2023-05-25 Ole Løseth Elvetun , Bjørn Fredrik Nielsen

The virtues of an effective field theory (EFT) approach to many-body problems are illustrated by deriving the expansion for the energy of an homogeneous, interacting Fermi gas at low density and zero temperature. A renormalization scheme…

Nuclear Theory · Physics 2009-11-06 H. -W. Hammer , R. J. Furnstahl

The development of a modern and more realistic nuclear energy density functional (EDF) for accurate predictions of properties of nuclei is the subject of enhanced activity, since it is very important for the study of properties of nuclear…

Nuclear Theory · Physics 2019-11-14 S. Shlomo , A. I. Sanzhur

We present a relativistic correction scheme to improve the accuracy of 1s core-level binding energies calculated from Green's function theory in the $GW$ approximation, which does not add computational overhead. An element-specific…

Chemical Physics · Physics 2020-09-23 Levi Keller , Volker Blum , Patrick Rinke , Dorothea Golze

Hubertus J. J. van Dam [Phys. Rev. A 93, 052512, 2016] claims that the one-particle reduced density matrix (1RDM) of an interacting system can be represented by means of a single-determinant wavefunction of fictitious non-interacting…

Chemical Physics · Physics 2017-10-20 Mario Piris , Katarzyna Pernal
‹ Prev 1 3 4 5 6 7 10 Next ›