报告题目:From Weyl conjecture to fundamental gap conjecture and beyond
报 告 人:包维柱 教授 (National University of Singapore)
报告时间:5月14日 10:00-12:00
报告地点:明理楼C302B
报告人简介:
包维柱教授现为新加坡国立大学(NUS)理学院副院长,新加坡科学院院士,美国工业与应用数学学会会士(SIAM Fellow),美国数学会会士(AMS Fellow)。1987-1995就读于清华大学数学系,先后获学士、硕士和博士学位。曾先后在清华大学、英国帝国理工学院及美国佐治亚理工学院任教、做博士后或访问学者。2001年起,在新加坡国立大学工作,并于2009年晋升为教授。现为该校数学系provost’s讲座教授。此外2011年起,兼职于北京计算科学研究中心,任客座教授,指导博士后研究工作。2013年获冯康科学计算奖,2014年应邀在第26届国际数学家大会(ICM)上作45分钟邀请报告,2024年被选为国际工业与应用数学联盟(ICIAM)的Officer-at-Large,担任包括SIAM Journal on Scientific Computing等多个国际期刊杂志编委。包维柱教授长期从事科学与工程计算研究,主要工作涉及偏微分方程数值方法及其在量子物理、流体和材料中的应用。特别是在Bose-Einstein 凝聚的数值方法及应用、高震荡色散类偏微分方程的多尺度算法和分析、无界区域上科学和工程问题的计算等方面取得了多个重要进展。
报告内容摘要:
In this talk, I begin with the eigenvalue problem of the Laplacian and Schroedinger operators (LO/SO) on bounded domains with homogeneous Dirichlet boundary condition and present the Weyl's law and Weyl conjecture on the asymptotics of the eigenvalues. Then I discuss several cases that many (hundreds to thousands) eigenvalues need to be computed numerically and accurately. Spectral and spectral-element methods are presented to discretize the eigenvalue problem on simple and complicated geometries, respectively. Numerical results are reported for the eigenvalue asymptotics beyond the Weyl conjecture, with Rubin boundary condition, SO-LO gaps, Rubin-Neumann gaps, and for the fractional Schroedinger operators (FSO). Based on our numerical results, some conjectures are formulated. Then I review the fundamental gap conjecture -- difference between the first two smallest eigenvalues -- of the LO/SO. Again, based on our recent asymptotic and numerical results, we propose a gap conjecture on the fundamental gap of the FSO. In addition, different gaps of eigenvalues of the FSO are discussed and the ``unfolding'' gaps statistics of FSO is reported. Finally, fundamental gaps on energy and chemical potential of the Gross-Pitaevskii equation are studied asymptotically and numerically.
主办单位:理学院
人工智能研究院
科学技术发展研究院