General Relativity and its Problems in China
Recently, I have done some search on the status of General Relativity in China. I do this because I am surprised from emails received that the outstanding work of Zhou-Pei-Yuan seems still not well-understood in China since 1983.
In my search, recently I come across to the popular video lecture of Professor T. P. Leung (梁燦彬), whom I met in 1992 when I first came to China to lecture general relativity. I particularly remember that he has been with Robert M. Wald of Chicago University for a year. Then, I said that I am glad to meet him and believe that he must have found all the errors of Wald. However, at that time, he did not answer this question of mine.
Now, form his video open lectures (微分幾何與廣義相對論教程), it is clear that he has learned a lot during the past 20 years. However, to my disappointment, he still has not rectified the errors of Wald; and still do not understand Einstein's equivalence principle. I wish to congratulate him for his greatly broadening of knowledge in differential geometry. However, it seems to me that he also should go back to read the 1916 initial article of Einstein on general relativity and his book of 1923, "The principle of general relativity". Then, he can understand the basics of general relativity, in particular Einstein's equivalence principle.
Moreover, he also does not understand that Yang-Mills-Shaw theory of 1954 is not the same as the non-abelian theories in physics. They did not see that the gauge invariance is a problematic notion in physics because Aharonov & Bohm showed that the electromagnetic potentials actually are physically effective in1959. As Weinberg pointed out, there are many problems including errors in the Yang-Mills-Shaw theory.
I understand that many Chinese physicists are proud of the Yang-Mills-Shaw theory probably because Yang is a Chinese American. However, they should understand also Yang’s errors are also obstacles to recognizing the merits of the excellent work of Zhou Pei-Yuan, who is a Chinese citizen.
Since now Professor Leung has a very influential forum, he can be very constructive and also destructive to the study of general relativity and also physics in China. For this, I wish him good luck in the future!