My advice is what you don't want to hear. Go learn about another topic to postgraduate level if you really want to be at the forefront of a particular topic. P

My advice is what you don't want to hear. Go learn about another topic to postgraduate level if you really want to be at the forefront of a particular topic. Pretty much every topic has extremely interesting and unsolved problems, but to solve them you more often than not need deep domain knowledge, or multiple supervisors (but I don't recommend that at all!).