应数学与统计学院的邀请，英国剑桥大学Arieh Iserles教授于5月16日-23日来我校进行学术交流并作学术报告。  
    1.报告题目: On the importance (and perils) of being skew-symmetric
       时       间：5月19日(周一)上午10:00
       地       点：理科楼202室
       报告摘要: In this talk we go back to the very basics of numerical analysis of PDEs, stability theory of finite difference schemes for linear evolution equations with variable coefficients. We prove that a universal "magic wand" renders numerical methods stable: the (first) space derivative should be discretised by a skew-symmetric matrix. The downside, however, is a barrier of 2 on the order of such methods on uniform grids. We derive a general theory coupling grid structure with the availability of skew-symmetric matrices corresponding to high-order methods.
    2.报告题目: Fast computation of the semiclassical Schrodinger equation
       时        间：5月21日(周三)上午10:00
       地        点：理科楼407室
       报告摘要: The computation of the semiclassical Schodinger equation presents a number of difficult challenges because of the presence of high oscillation and the need to respect unitarity. Typical strategy involves a spectral method in space and Strang splitting in time, but it is of low accuracy and sensitive to high oscillation. In this talk we sketch an alternative strategy, based on high-order symmetric Zassenhaus splittings, combined with spectral collocation, which preserve unitarity and whose accuracy is immune to high oscillation. These splittings can be implemented with large time steps and allow for an exceedingly affordable computation of underlying exponentials.