I've just finished my undergraduate education in Physics in Europe and as I want to stay in academics I want to pursue a PhD, which means either a master and then PhD in e.g. UK, Switzerland or Germany or a PhD in the United States. I have now heard that for postdoc positions especially in the US it is generally better to have a US PhD. Is that true?
As the higher education systems are quite different and I have already attended courses like advanced quantum field theory or general relativity and the core courses like qm, classical mechanics, statistical mechanics or e&m on graduate level for my bachelors degree, is it generally the case, that I would have to take those courses again?