No, there is no coursework past a master’s thesis. For the last typically ~3-4 years of graduate training, everything that you’re doing is original research. If your research isn’t good enough or done correctly, you will never get a PhD. You also have to defend your dissertation. Getting a PhD from a reputable university does mean that what you say, specifically related to your research area, is correct.
The PHD means you passed your classes. It doesn’t mean anything you say is right.
No, there is no coursework past a master’s thesis. For the last typically ~3-4 years of graduate training, everything that you’re doing is original research. If your research isn’t good enough or done correctly, you will never get a PhD. You also have to defend your dissertation. Getting a PhD from a reputable university does mean that what you say, specifically related to your research area, is correct.