English
Related papers

Related papers: Avoid the Tsunami of the Dirac sea in the Imaginar…

200 papers

Stochastic quantum trajectories, such as pure state evolutions under unitary dynamics and random measurements, offer a crucial ensemble description of many-body open system dynamics. Recent studies have highlighted that individual quantum…

Quantum Physics · Physics 2026-01-07 Shivan Mittal , Bin Yan

An embedding method for solving the time-dependent Schr\"odinger equation is developed using the Dirac-Frenkel variational principle. Embedding allows the time-evolution of the wavefunction to be calculated explicitly in a limited region of…

Mesoscale and Nanoscale Physics · Physics 2015-05-27 J. E. Inglesfield

Current spectral simulations of Einstein's equations require writing the equations in first-order form, potentially introducing instabilities and inefficiencies. We present a new penalty method for pseudo-spectral evolutions of second order…

General Relativity and Quantum Cosmology · Physics 2014-11-21 Nicholas W. Taylor , Lawrence E. Kidder , Saul A. Teukolsky

This paper develops a high-accuracy algorithm for time fractional wave problems, which employs a spectral method in the temporal discretization and a finite element method in the spatial discretization. Moreover, stability and convergence…

Numerical Analysis · Mathematics 2017-08-10 Binjie Li , Hao Luo , Xiaoping Xie

We present a multi-dimensional numerical code to solve isothermal magnetohydrodynamic (IMHD) equations for use in modeling astrophysical flows. First, we have built a one-dimensional code which is based on an explicit finite-difference…

Astrophysics · Physics 2009-10-31 Jongsoo Kim , Dongsu Ryu , T. W. Jones , S. S. Hong

The smoothed-particle hydrodynamics (SPH) technique is a numerical method for solving gas-dynamical problems. It has been applied to simulate the evolution of a wide variety of astrophysical systems. The method has a second-order accuracy,…

Instrumentation and Methods for Astrophysics · Physics 2016-08-08 Domingo García-Senz , Rubén M. Cabezón , José A. Escartín , Kevin Ebinger

A relativistic transient absorption theory is derived, implemented and validated within the dipole approximation based on the time-dependent Dirac equation. Time-dependent simulations have been performed using the Dirac equation and the…

Atomic Physics · Physics 2020-10-14 Felipe Zapata , Jimmy Vinbladh , Eva Lindroth , Jan Marcus Dahlström

The incompressible smoothed particle hydrodynamics method (ISPH) is a numerical method widely used for accurately and efficiently solving flow problems with free surface effects. However, to date there has been little mathematical…

Numerical Analysis · Mathematics 2019-07-03 Y. Imoto

We propose a new method to solve the relativistic hydrodynamic equations based on implicit Runge-Kutta methods with a locally optimized fixed-point iterative solver. For numerical demonstration, we implement our idea for ideal hydrodynamics…

Nuclear Theory · Physics 2024-04-16 Nathan Touroux , Masakiyo Kitazawa , Koichi Murase , Marlene Nahrgang

The article deals with a classical inverse problem: the computation of the refractive index of a medium from ultrasound time-of-flight (TOF) measurements. This problem is very popular in seismics but also for tomographic problems in…

Numerical Analysis · Mathematics 2016-08-03 Udo Schroeder , Thomas Schuster

We introduce a lattice model for a static and isotropic system of relativistic fermions. An action principle is formulated, which describes a particle-particle interaction of all fermions. The model is designed specifically for a numerical…

Mathematical Physics · Physics 2014-11-18 Felix Finster , Wätzold Plaum

A method is proposed for extracting ionization amplitudes from the solution of the time-dependent Schr\"odinger equation (TDSE) describing a system in a time-dependent external field. The method is a hybrid of two earlier developed methods,…

Atomic Physics · Physics 2013-10-30 Vladislav V. Serov , Tatyana A. Sergeeva , Sergue I. Vinitsky

The Fisher information theory sets a fundamental bound on the minimum measurement error achievable from independent and identically distributed (i.i.d.) measurement events. The assumption of identical and independent distribution often…

Optics · Physics 2025-06-09 S. Kim , J. Stohr , B. S. Ham

We present a mathematical approach that simplifies the theoretical treatment of electromagnetic localization in random media and leads to closed form analytical solutions. Starting with the assumption that the dielectric permittivity of the…

Optics · Physics 2009-11-13 Dimitris Dimitropoulos , Bahram Jalali

A fast and stable method is formulated to compute the time evolution of a wavefunction by numerically solving the time-dependent Schr{\"o}dinger equation. This method is a real space/real time evolution method implemented by several…

Computational Physics · Physics 2009-11-06 Naoki Watanabe , Masaru Tsukada

Gravitational wave signals from extreme mass ratio inspirals are a key target for space-based gravitational wave detectors. These systems are typically modeled as a distributionally-forced Teukolsky equation, where the smaller black hole is…

General Relativity and Quantum Cosmology · Physics 2025-09-16 Manas Vishal , Scott E. Field , Katie Rink , Sigal Gottlieb , Gaurav Khanna

The periodic, inverse scattering transform (PIST) is a powerful analytical tool in the theory of integrable, nonlinear evolution equations. Osborne pioneered the use of the PIST in the analysis of data form inherently nonlinear physical…

Fluid Dynamics · Physics 2009-09-22 Ivan Christov

Spatially localized structures are key components of turbulence and other spatio-temporally chaotic systems. From a dynamical systems viewpoint, it is desirable to obtain corresponding exact solutions, though their existence is not…

Chaotic Dynamics · Physics 2014-05-21 Toshiki Teramura , Sadayoshi Toh

A Finite-Difference Time-Domain (FDTD) scheme with Perfectly Matched Layers (PMLs) is considered for solving the time-dependent Schr\"{o}dinger equation, and simulate the ionization of an electron initially bound to a one-dimensional…

Mesoscale and Nanoscale Physics · Physics 2020-04-02 Høgni C. Kamban , Sigurd S. Christensen , Thomas Søndergaard , Thomas G. Pedersen

A new fluid model for runaway electron simulation based on fluid description is introduced and implemented in the magnetohydrodynamics code M3D-C1, which includes self-consistent interactions between plasma and runaway electrons. The model…

‹ Prev 1 8 9 10 Next ›