【系综合学术报告】

报告题目：Extension principles for the Einstein Yang-Mills system

报告人：王金花，厦门大学

时间：2026年1月8日（周四） 下午1:30

地点：文北楼102

摘要：We prove the local existence theorem and establish an extension principle for the spherically symmetric Einstein Yang-Mills system (SSEYM) with $H^1$ data, which further implies Cauchy stability for the system. Based on this result, we further prove an extension theorem for developments of weighted $H^1$ data. The weighted $H^1$ space allows H\"{o}lder continuous data. In contrast to a massless scalar field, the purely magnetic Yang--Mills field in spherical symmetry satisfies a wave-type equation with a singular potential.  As a consequence, the proof of Christodoulou, based on an $L^\infty-L^\infty$ estimate, fails in the Yang--Mills context. Instead, we employ an $L^2$-based method, which is valid for both massless and massive  scalar matter fields as well. These are based on joint works with Junbin Li.

报告题目：Instability of naked singularities: Exterior and Interior

报告人：黎俊彬，中山大学

时间：2026年1月8日（周四） 下午2:30

地点：文北楼102

摘要：We will first review some exterior results in the instability of naked singularities. Then we present a new approach to proving instability under interior perturbations, and its implications in the weak cosmic censorship conjecture, one of the most fundamental questions in general relativity.

邀请人：于品