Greg Moore (Popularity: )
http://www.physics.rutgers.edu/~gmoore/ Rutgers University. Research on string theory and M-theory, with a particular emphasis on the underlying mathematical structures and applications to and from modern mathematics.
Baez, John (Popularity: )
http://math.ucr.edu/home/baez/ University of California Riverside. Research interests: quantum gravity and n-categories. Regular column on "This Week's Finds in Mathematical Physics".