The unity of opposites and the fundamental problem of modern theoretical physics

Up to now, mankind has made many fascinating discoveries. Those related to the science of physics have greatly contributed to the rapid technological development of human civilization. Considering all the triumphs of scientific thought in the past and nowadays, we are all surprised by the contradiction that arose in theoretical physics in late 19th century. Even now, interpreting the Universe is involved with the challenge. Therefore, the top priority task is, How can we resolve this contradiction?