breakthrough propulsion research

If one wanted to pursue a career in researching breakthrough propulsion ideas would you want to pursue a degree in physics or aerospace engineering?

If you want to go into an engineering field of that type, I would say you would need all the math intensive courses you could take, as well as both the degrees you are talking about. Also, something like this would almost definatly be linked to a military or gov orginazation, so a little military background might be to your advantage as well. Good Luck