報告題目:Fast algorithm for convolution-type potential evaluation in quantum mechanics and engineering problems(系列講座)
主講人:張勇教授(天津大學(xué)應(yīng)用數(shù)學(xué)中心)
時間:
系列講座之一:2020年10月19日(周一)10:30 a.m.
系列講座之二:2020年10月26日(周一)10:30 a.m.
系列講座之三:2020年11月2日(周一)10:30 a.m.
形式:線上講座
主辦單位:統(tǒng)計與數(shù)學(xué)學(xué)院
會議鏈接:
系列講座之一:https://meeting.tencent.com/s/S2218JFQTYCq
系列講座之二:https://meeting.tencent.com/s/UjDyv201PWNB
系列講座之三:https://meeting.tencent.com/s/UjDyv201PWNB
摘要:Convolution-type potential are common and important in many science and engineering fields. Efficient and accurate evaluation of such nonlocal potentials are essential in practical simulations. In this serial-talk, I will focus on those arising from quantum physics/chemistry and lightning-shield protection, including Coulomb, dipolar and Yukawa potential that are generated by isotropic and anisotropic smooth and fast-decaying density, as well as convolutions defined on a one-dimensional adaptive finite difference grid. The convolution kernel is usually singular or discontinuous at the origin and/or at the far field, and density might be anisotropic, which together present great challenges for numerics in both accuracy and efficiency. The state-of-art fast algorithms include Wavelet based Method( WavM), kernel truncation method(KTM), NonUniform-FFT based method(NUFFT) and Gaussian-Sum based method(GSM). Gaussian-sum/exponential-sum approximation and kernel truncation technique, combined with finite Fourier series and Taylor expansion, finally lead to a O(N log N) algorithm achieving spectral accuracy. For the one-dimensional convolutions, we shall introduce the tree and sum-of-exponential based fast algorithm.
Part I:The series topic will cover the following topics
Spectral method on bounded domain and PDE-based algorithm
Part II:The series topic will cover the following topics
(1)NUFFT-based fast convolution solver and related application
(2) GauSum approximation and Fast Convolution Solver
Part III:The series topic will cover the following topics
1) Kernel truncation method and Anisotropic Kernel Truncation method
2) Fast one-dimensional Solver based on Sum-Of-Exponentials
主講人簡介:
張勇,男,,天津大學(xué)應(yīng)用數(shù)學(xué)中心。2012年于清華大學(xué)數(shù)學(xué)學(xué)院取得博士學(xué)位后,,于奧地利維也納大學(xué)Wolfgang Pauli研究所,、美國著名的數(shù)學(xué)研究所——克朗數(shù)學(xué)研究所等地進行博士后研究。近年來,,張勇博士在快速算法設(shè)計與相關(guān)物理應(yīng)用取得了不少先進的研究成果,。