English
Related papers

Related papers: Domain decomposition and multilevel integration fo…

200 papers

We perform a reduction from three to two spatial dimensions of the physics of a spin-1/2 fermion coupled to the electromagnetic field, by applying Hadamard's method of descent. We consider first the free case, in which motion is determined…

Mean-field molecular dynamics based on path integrals is used to approximate canonical quantum observables for particle systems consisting of nuclei and electrons. A computational bottleneck is the sampling from the Gibbs density of the…

Numerical Analysis · Mathematics 2023-11-30 Xin Huang , Petr Plechac , Mattias Sandberg , Anders Szepessy

The problem of confinement of fermions in 1+1 dimensions is approached with a linear potential in the Dirac equation by considering a mixing of Lorentz vector and scalar couplings. Analytical bound-states solutions are obtained when the…

High Energy Physics - Theory · Physics 2009-11-07 Antonio S. de Castro

We present a method to compute the Fermi function of the Hamiltonian for a system of independent fermions, based on an exact decomposition of the grand-canonical potential. This scheme does not rely on the localization of the orbitals and…

Materials Science · Physics 2009-11-13 Michele Ceriotti , Thomas Kuehne , Michele Parrinello

A general algorithm toward the solution of the fermion sign problem in finite-temperature quantum Monte Carlo simulations has been formulated for discretized fermion path integrals with nearest-neighbor interactions in the Trotter…

Statistical Mechanics · Physics 2009-10-31 C. H. Mak , R. Egger , H. Weber-Gottschick

With a non-unitary transformation, the Lagrangian of a Dirac fermion is decomposed into two decoupled sectors. We propose to describe massive relativistic fermions in gauge theories in a two-component form. All relations between the Green's…

High Energy Physics - Phenomenology · Physics 2007-05-23 YU-Qi Chen

In this work we study a system of two distinguishable fermions in a 1D harmonic potential. This system has the exceptional property that there is an analytic solution for arbitrary values of the interparticle interaction. We tune the…

Quantum Gases · Physics 2013-07-16 G. Zürn , F. Serwane , T. Lompe , A. N. Wenz , M. G. Ries , J. E. Bohn , S. Jochim

We investigate fermionic quantum field theories using functional renormalisation. In the limit of many fermion flavours $N$, we demonstrate that theories have exact solutions for their quantum effective actions given by quasi-local…

High Energy Physics - Theory · Physics 2025-02-10 Charlie Cresswell-Hogg , Daniel F. Litim

We derive the spherical field formalism for fermions. We find that the spherical field method is free from certain difficulties which complicate lattice calculations, such as fermion doubling, missing axial anomalies, and computational…

High Energy Physics - Theory · Physics 2009-10-31 Dean Lee

Among many types of quantum entanglement properties, the entanglement spectrum provides more abundant information than other observables. Exact diagonalization and density matrix renormalization group method could handle the system in…

Strongly Correlated Electrons · Physics 2025-03-05 Weilun Jiang , Xiaofan Luo , Bin-Bin Mao , Zheng Yan

This paper presents a novel factorization-based, low-rank regularization method for solving multidimensional deconvolution problems in the frequency domain. In this approach, each frequency component of the unknown wavefield is represented…

Geophysics · Physics 2024-10-29 Fuqiang Chen , Matteo Ravasi , David Keyes

Domain-wall fermions preserve chiral symmetry up to terms that decrease exponentially when the lattice size in the fifth dimension is taken to infinity. The associated rates of convergence are given by the low-lying eigenvalues of a simple…

High Energy Physics - Lattice · Physics 2007-05-23 P. Hernández , K. Jansen , M. Lüscher

A spectroscopic method for staggered fermions based on thermodynamical considerations is proposed. The canonical partition functions corresponding to the different quark number sectors are expressed in the low temperature limit as…

High Energy Physics - Lattice · Physics 2008-11-26 Z. Fodor , K. K. Szabo , B. C. Toth

The computation of Feynman integrals is often the bottleneck of multi-loop calculations. We propose and implement a new method to efficiently evaluate such integrals in the physical region through the numerical integration of a suitable set…

High Energy Physics - Phenomenology · Physics 2019-05-01 Manoj K. Mandal , Xiaoran Zhao

For several decades it has been known that divergences arise in the ground-state energy and chemical potential of unitary superfluids, where the scattering length diverges, due to particle-hole scattering. Leading textbooks and research…

Quantum Gases · Physics 2025-08-27 Nikolai Kaschewski , Axel Pelster , Carlos A. R. Sá de Melo

The Monte Carlo calculation of R\'enyi entanglement entropies $S^{}_n$ of interacting fermions suffers from a well-known signal-to-noise problem, even for a large number of situations in which the infamous sign problem is absent. A few…

Strongly Correlated Electrons · Physics 2015-10-28 Joaquín E. Drut , William J. Porter

We propose a randomized algorithm to compute the log-partition function of weakly interacting fermions with polynomial runtime in both the system size and precision. Although weakly interacting fermionic systems are considered tractable for…

We propose an interaction flow scheme that sums up the perturbation expansion of many-particle systems by successively increasing the interaction strength. It combines the unbiasedness of renormalization group methods with the simplicity of…

Strongly Correlated Electrons · Physics 2007-05-23 Carsten Honerkamp , Daniel Rohe , Sabine Andergassen , Tilman Enss

The numerical and computational aspects of chiral fermions in lattice quantum chromodynamics are extremely demanding. In the overlap framework, the computation of the fermion propagator leads to a nested iteration where the matrix vector…

High Energy Physics - Lattice · Physics 2009-11-10 Nigel Cundy , Andreas Frommer , Jasper van den Eshof , Thomas Lippert , Stephan Krieg , Katrin Schäfer

Many fMRI analyses examine functional connectivity, or statistical dependencies among remote brain regions. Yet popular methods for studying whole-brain functional connectivity often yield results that are difficult to interpret. Factor…

Methodology · Statistics 2024-09-24 Kyle Stanley , Nicole Lazar , Matthew Reimherr