Hi, I have finished 2 years studying physics, and 1 year studying teaching physics. From the first lecture in the university, students are taught that physics is an experimental science. The strength of physics is that it could be verified experimentally. If someone has some doubts regarding any principle, he/she can check it experimentally. My problem is that in modern physics, it seems that physics started to study things that could not be verified repeatedly by experiments. At best, we can seek for some motivations for our theory. The problem is that such theories give the rise of much arguing. Physics seems to lose its strength due to the lack of repeated experimental verification. For example, consider the Big Bang theory, although there are many of motivations to think about it, yet it could not be verified experimentally, and so we have much of arguing about it. Google can give tons of doubts about Big Bang. Does the Big Bang theory lie within the scope of physics, so it could be verified without any doubts by experiments? I thought that there is no place for arguing in physics because everything could be judged by experiments. Was I wrong? May anybody please help me understands this issue? I have got tired thinking about it, please help!