From Newton's law of universal gravitation to Einstein's general theory of relativity is a qualitative leap in human understanding of the essence of gravitation. Over the past 100 years, various experimental observations, recent direct observations of gravitational waves and photos of black holes have verified the general theory of relativity, but the essence of gravity is still a major topic of basic science in the 21st century. The report will briefly introduce Einstein's general theory of relativity, its four classical tests and its two predictions - gravitational waves and black holes, as well as related important scientific problems.

Researcher, Institute of theoretical physics, Chinese Academy of Sciences, member of the 13th CPPCC National Committee. He was co elected as an academician of the Chinese Academy of Sciences in 2017, a member of the international society of general relativity and gravity in 2019 and an academician of the Academy of Sciences of developing countries in 2020. Now he is also the executive director of the Chinese physical society, the director of the Academic Exchange Committee, the director of the branch of gravitation and Relativistic Astrophysics, the director of the international society of general relativity and gravitation, the vice president of the branch of astrophysics, gravitation and cosmology of the Asia Pacific physical society, and the president of the BRICs society of gravitation, astrophysics and cosmology. In the research field of gravity theory and cosmology, he has published more than 280 academic papers on gravity theory, string theory, black hole physics, early universe, dark energy, and gravitational wave physics, which have been cited more than 17000 times. He has won the second prize of the National Natural Science Award and the Thomson Reuters global highly cited Scientist Award.