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Positivities, Semigroups, and the Sign Problem in Quantum Monte Carlo Simulations

发布日期:2024-04-19


报告题目:Positivities, Semigroups, and the Sign Problem in Quantum Monte Carlo Simulations

报告人:魏忠超

邀请人:郑雨军、赵翀

报告时间:2024年4月23日下午2:30 ~ 4:30

报告地点:知新楼C座1011会议室

报告人简介:

魏忠超,博士,2016年在中国科学院大学中国科学院物理研究所获得博士学位,导师为向涛院士。随后在德国科隆大学从事博士后研究工作,导师为Martin Zirnbauer教授。主要研究兴趣在物理强关联电子系统,利用数学物理从事与张量网络态算法和蒙特卡洛算法有关的理论工作。相关研究工作发表在Phys. Rev. Lett.,Phys. Rev. B,Chin. Phys. Lett.等。

内容提要:

We propose a new framework based on the concept of semigroup to understand the fermion sign problem. By using properties of contraction semigroups, we obtain new sufficient conditions for quantum lattice fermion models to be sign-problem-free. By relating these two class of sign-problem-free models to Majorana reflection positivity and time-reversal positivity respectively, we can immediately have a Perron-Frobenius type theorem, which generalizes previous results by E. H. Lieb.