FST Distinguished Talk – From the Variational Principle to the Inverse Function TheoremSpeaker: Dr. Ivar I. Ekeland from French National Centre for Scientific Research

Faculty of Science and Technology (FST) at the University of Macau hosted a distinguished lecture by Prof. Ivar I. Ekeland, world-renowned mathematician and originator of Ekeland’s Variational Principle, on 19 November 2025. The event drew a full house of faculty, researchers, and students for his talk titled “From the Variational Principle to the Inverse Function Theorem.”

In his presentation, Prof. Ekeland demonstrated how his variational principle can be used to derive a powerful generalization of the inverse function theorem—even in settings where traditional differentiability fails. He covered both classical Banach space cases and the more intricate Nash-Moser scenario, highlighting applications in nonlinear analysis and partial differential equations. A Fellow of the Royal Society of Canada and member of several national academies, Prof. Ekeland captivated the audience with his clarity, depth, and ability to connect abstract theory to real-world mathematical challenges. The talk was hosted by Prof. Chang Feng Gui and followed by a lively Q&A session, reflecting strong engagement from attendees across disciplines.

In the future, FST will continue its commitment to fostering high-level academic exchange through such distinguished lectures, bridging global expertise with local scholarly communities.

澳門大學科技學院於2025年11月19日舉辦了一場由國際著名數學家、埃克朗變分原理（Ekeland’s Variational Principle）創立者Ivar I. Ekeland教授主講的傑出講座。題為《從變分原理到反函數定理》的演講吸引了眾多教師、研究人員和學生出席。

在演講中，Ekeland教授展示了如何運用其變分原理推導出反函數定理的一個強有力推廣——即便在傳統可微性條件失效的情形下依然成立。他深入淺出地探討了經典巴拿赫空間情形以及更為複雜的納什–莫澤（Nash-Moser）框架，並強調了該理論在非線性分析與偏微分方程中的重要應用。作為加拿大皇家學會會士及多個國家科學院院士，Ekeland教授以其清晰的邏輯、深厚的學養以及將抽象理論與現實數學問題相聯繫的能力深深打動了在場聽眾。本次講座由桂長峰教授主持，隨後的問答環節氣氛熱烈，充分體現了跨學科聽眾的高度參與。

未來，科技學院將繼續透過此類高水準學術講座促進國際前沿知識與本地學術社群的深度融合，推動高質量的學術交流。