Theoretical physics research in string theory will include the study of black hole thermodynamics using methods of both string theory and polymer physics, and the elucidation of geometric structures of "M-theory," which underlies string theory. The statistical basis of black hole thermodynamics is at the heart of understanding quantum gravity, and hence is important to understanding the underlying theory of all fundamental interactions. Surprising connections with "soft matter" and biophysical systems are to be further explored with potentially valuable applications. Recent advances reveal that M-theory, the theory unifying the five distinct superstring theories, has an even richer geometrical structure than had been previously realized and which points to new phases of M-theory as well as possible implications for inflationary cosmology of the universe. The planned work promises to shed light on the underlying structure of the unified theory and on the explanation of the origin and evolution of the early universe.