主講人：周德堂 巴西Fluminense聯邦大學教授

時間：2025年6月28日10：00

地點：徐匯校區三號樓332室

舉辦單位：數理學院

主講人介紹：周德堂，巴西 Fluminense聯邦大學教授。 1991年博士畢業于山東大學。曾為山東大學教授，復旦大學、日本東北大學博士后， IMPA、 IHES、加州大學、 MIT等訪問教授。研究成果發表在 J. Diff. Geom., Trans. Amer. Math. Soc., Math. Ann., Amer. J. Math., Crelle Journal等國際知名雜志上 。

內容介紹：We show that the spectrum is discrete when the potential function is proper, and we show that the hypothesis on the properness of the potential function cannot be removed. We conclude that the drift Laplacian has a discrete spectrum on Ricci expanders whose Ricci curvature is bounded below by a suitable constant. Further, we compute all the eigenvalues of the drift Laplacian on rigid expanders and rigid shrinkers. Lastly, we investigate the second eigenvalue of the drift Laplacian on rigid Ricci expanders whose Einstein factor is a closed hyperbolic Riemann surface. This is joint work with H. Leal and M. Vieira.