Wim Ubachs
Department of Physics and Astronomy, LaserLaB, VU University, Amsterdam
Precision measurements can be performed on hydrogen molecules. Lasers and precision frequency metrology methods can be used to determine the level structure of the smallest neutral molecule to high accuracy. Comparison with the best ab initio calculations, which nowadays cover relativistic effects and quantum electrodynamical effects then provide a test of QED in a system with a molecular bond. These results can be interpreted as an upper bound of possible hadronic forces beyond the Standard Model. Hydrogen is also the most abundant molecule in the Universe and can be detected at high redshift (z=2-3), corresponding to look-back times of 10-12 billion years. Observations of H2 molecular lines can be interpreted in terms of a possible drift of the proton-electron mass ratio over cosmic time.
报告时间：7月16日（周二）下午4:00
报告地点：东区理化大楼9004会议室
报告人简介：Wim Ubachs，荷兰VU阿姆斯特丹大学物理与天文系教授，2012年Templeton基金会“天文和宇宙学新前沿”奖获得者。研究方向为激光光谱学，最近几年的系列工作精密测定了H2等基本分子常数，并探索基于这些基本测量来研究宇宙中基本物理常数的变化、甚至是否存在“第五种力”等物理和天文学基础问题，最近系列工作发表在Science、PRL杂志上，在光谱学界和天文学界都引起了极大兴趣。
主办单位：化学与材料科学学院、合肥微尺度物质科学国家实验室