If You Ask Me

I want to work on Robert Lowell in my dissertaion, so can anyone provide me with a potential theme?

If you're having trouble coming up with a theme on your own, then maybe you need to rethink writing about Lowell. You'll be more successful if you'll write your dissertation on a subject you feel passionately about, that you have so many insights about that you just can't wait to get them down on paper.

Good luck!

Robert Lowell is one of my favorite poets.

A few suggestions might be how his imprisonment during WWII as a conscientious objector affected his work.  Another avenue might be to consider Lowell's stature and viability as the "father" of confessional poetry.  Lowell has also been called one of the two modern poets deserving of the title "Major Poet" by Peter Davison (the other was James Dickey).  You might offer a reconsideration of the title (see Davison's work, The Difficulties of Being Major) as this pronouncement was made in 1976. 

Much has been written about his madness, and you'd have to find your own angle, but some good places to start would be to read Ian Hamilton's extensive biography of Lowell's life, and The Mad Poet's Society by Alex Beam.