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Related papers: Cost Reduction in Spin-dependent Stochastic GW Cal…

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We present an approach for GW calculations of quasiparticle energies with quasi-quadratic scaling by approximating high-energy contributions to the Green's function in its Lehmann representation with effective stochastic vectors. The method…

Materials Science · Physics 2023-12-07 Aaron R. Altman , Sudipta Kundu , Felipe H. da Jornada

We propose and implement a novel hybrid meta-heuristic optimization algorithm for the identification of non-collinear global ground-states in magnetic systems. The inputs to this optimization scheme are directly from non-collinear density…

Materials Science · Physics 2023-10-03 Guy C. Moore , Matthew K. Horton , Kristin A. Persson

We present two methods for determining the significance of a stochastic gravitational-wave (GW) background affecting a pulsar-timing array, where detection is based on evidence for quadrupolar spatial correlations between pulsars. Rather…

Instrumentation and Methods for Astrophysics · Physics 2017-02-13 S. R. Taylor , L. Lentati , S. Babak , P. Brem , J. R. Gair , A. Sesana , A. Vecchio

A spin-wave (SW) approach for hard-core bosons is presented to treat the problem of two dimensional boson localization in a random potential. After a short review of the method to compute 1/S-corrected observables, the case of random…

Strongly Correlated Electrons · Physics 2014-12-04 Juan Pablo Álvarez Zúñiga , Gabriel Lemarié , Nicolas Laflorencie

Semiclassical expansion of the Wigner function for spin-1/2 fermions having an effective spacetime-dependent mass is used to analyze spin-polarization effects. The existing framework is reformulated to obtain a differential equation…

High Energy Physics - Phenomenology · Physics 2024-01-24 Samapan Bhadury , Arpan Das , Wojciech Florkowski , Gowthama K. K. , Radoslaw Ryblewski

This work analyzes the overall computational complexity of the stochastic Galerkin finite element method (SGFEM) for approximating the solution of parameterized elliptic partial differential equations with both affine and non-affine random…

Numerical Analysis · Mathematics 2020-01-22 Nick Dexter , Clayton Webster , Guannan Zhang

This paper extends the application of the stochastic variational method to noncentral interactions. Several examples are presented for three- and four-nucleon systems with realistic nuclear forces. The correlated Gaussians easily cope with…

Nuclear Theory · Physics 2009-10-30 K. Varga , Y. Ohbayasi , Y. Suzuki

A description of non-collinear magnetism in the framework of spin-density functional theory is presented for the exact exchange energy functional which depends explicitly on two-component spinor orbitals. The equations for the effective…

Special stochastic representation of the wave function in Quantum Mechanics (QM), based on soliton realization of extended particles, is suggested with the aim to model quantum states via classical computer. Entangled solitons construction…

Quantum Physics · Physics 2007-05-23 T. F. Kamalov , Yu. P. Rybakov

The models of spin systems defined on Euclidean space provide powerful machinery for studying a broad range of condensed matter phenomena. While the non-relativistic effective description is sufficient for most of the applications, it is…

High Energy Physics - Theory · Physics 2020-12-29 Danilo Artigas , Jakub Bilski , Sean Crowe , Jakub Mielczarek , Tomasz Trześniewski

We review a recently proposed approach to construct gravitational wave (GW) polarization states of unbound spinning compact binaries. Through this rather simple method, we are able to include corrections due to the dominant order spin-orbit…

General Relativity and Quantum Cosmology · Physics 2015-06-11 Lorenzo De Vittori , Achamveedu Gopakumar , Anuradha Gupta , Philippe Jetzer

In this paper, we introduce a new stochastic approximation (SA) type algorithm, namely the randomized stochastic gradient (RSG) method, for solving an important class of nonlinear (possibly nonconvex) stochastic programming (SP) problems.…

Optimization and Control · Mathematics 2015-10-27 Saeed Ghadimi , Guanghui Lan

Spin space groups (SSGs) impose fundamentally different constraints on magnetic configurations in real and reciprocal spaces. As a consequence, the correspondence between real-space and momentum-space spin arrangements is far richer than…

Materials Science · Physics 2025-12-16 Ziyin Song , Ziyue Qi , Chen Fang , Zhong Fang , Hongming Weng

We present a data-efficient framework for constructing general classical spin Hamiltonians by combining the spin-cluster expansion (SCE) with fully self-consistent noncollinear spin density functional theory (DFT). The key idea is to fit…

Materials Science · Physics 2026-05-26 Tomonori Tanaka , Yoshihiro Gohda

Modeling a high-dimensional Hamiltonian system in reduced dimensions with respect to coarse-grained (CG) variables can greatly reduce computational cost and enable efficient bottom-up prediction of main features of the system for many…

Computational Engineering, Finance, and Science · Computer Science 2021-04-09 Shu Wang , Zhan Ma , Wenxiao Pan

An expression for the square of the spin operator expectation value, \textless{} S^2\textgreater{}, is obtained for a general complex Hartree-Fock (GCHF) wave function and decomposed into four contributions: The main one whose expression is…

Quantum Physics · Physics 2015-09-08 Patrick Cassam-Chenaï

We present a systematic approach for the semiclassical treatment of many-body dynamics of interacting, open spin systems. Our approach overcomes some of the shortcomings of the recently developed discrete truncated Wigner approximation…

Quantum Physics · Physics 2022-12-01 Christopher D. Mink , David Petrosyan , Michael Fleischhauer

Choosing the optimization algorithm that performs best on a given machine learning problem is often delicate, and there is no guarantee that current state-of-the-art algorithms will perform well across all tasks. Consequently, the more…

Optimization and Control · Mathematics 2024-06-25 Måns Williamson , Monika Eisenmann , Tony Stillfjord

Spinning neutron stars (NSs) can emit continuous gravitational waves (GWs) that carry a wealth of information about the compact object. If such a signal is detected, it will provide us with new insight into the physical properties of matter…

General Relativity and Quantum Cosmology · Physics 2023-09-12 Wen-Fan Feng , Tan Liu , Jie-Wen Chen , Yan Wang , Soumya D. Mohanty

The application of Gaussian processes (GPs) to large data sets is limited due to heavy memory and computational requirements. A variety of methods has been proposed to enable scalability, one of which is to exploit structure in the kernel…

Machine Learning · Computer Science 2019-12-30 Jan Graßhoff , Alexandra Jankowski , Philipp Rostalski