Zobrazeno 1 - 10
of 171
pro vyhledávání: '"Cai, Zhenning"'
We introduce a numerical solver for the steady-state Boltzmann equation based on the symmetric Gauss-Seidel (SGS) method. To solve the nonlinear system on each grid cell derived from the SGS method, a fixed-point iteration preconditioned with its asy
Externí odkaz:
http://arxiv.org/abs/2409.01910
We propose an algorithm that combines the inchworm method and the frozen Gaussian approximation to simulate the Caldeira-Leggett model in which a quantum particle is coupled with thermal harmonic baths. In particular, we are interested in the real-ti
Externí odkaz:
http://arxiv.org/abs/2408.01039
Time-dependent Regularized 13-Moment Equations with Onsager Boundary Conditions in the Linear Regime
We develop the time-dependent regularized 13-moment equations for general elastic collision models under the linear regime. Detailed derivation shows the proposed equations have super-Burnett order for small Knudsen numbers, and the moment equations
Externí odkaz:
http://arxiv.org/abs/2407.12845
We study the dynamical simulation of open quantum spin chain with nearest neighboring coupling, where each spin in the chain is associated with a harmonic bath. This is an extension of our previous work [G. Wang and Z. Cai, J. Chem. Theory Comput., 1
Externí odkaz:
http://arxiv.org/abs/2407.04365
Autor:
Dong, Xiaoyu, Cai, Zhenning
We study the iterative methods for large moment systems derived from the linearized Boltzmann equation. By Fourier analysis, it is shown that the direct application of the block symmetric Gauss-Seidel (BSGS) method has slower convergence for smaller
Externí odkaz:
http://arxiv.org/abs/2312.06191
We introduce numerical solvers for the steady-state Boltzmann equation based on the symmetric Gauss-Seidel (SGS) method. Due to the quadratic collision operator in the Boltzmann equation, the SGS method requires solving a nonlinear system on each gri
Externí odkaz:
http://arxiv.org/abs/2311.14138
The $\phi$-divergence-based moment method was recently introduced Abdelmalik et al. (2023) for the discretization of the radiative transfer equation. At the continuous level, this method is very close to the entropy-based MN methods and possesses its
Externí odkaz:
http://arxiv.org/abs/2310.05489
Autor:
Wang, Geshuo, Cai, Zhenning
We study the real-time simulation of open quantum systems, where the system is modeled by a spin chain, with each spin associated with its own harmonic bath. Our method couples the inchworm method for the spin-boson model and the modular path integra
Externí odkaz:
http://arxiv.org/abs/2307.03924
This paper presents a novel Fourier spectral method that utilizes optimization techniques to ensure the positivity and conservation of moments in the space of trigonometric polynomials. We rigorously analyze the accuracy of the new method and prove t
Externí odkaz:
http://arxiv.org/abs/2304.11847
The method of moments is widely used for the reduction of kinetic equations into fluid models. It consists in extracting the moments of the kinetic equation with respect to a velocity variable, but the resulting system is a priori underdetermined and
Externí odkaz:
http://arxiv.org/abs/2304.01758