  In this dissertation, we review work presented in arXiv:0906.2015,
arXiv:0907.1663, arXiv:1002.3132, arXiv:1003.2746, and arXiv:1007.2202 on the
D1D5 system. We begin with some motivational material for black holes in string
theory. In Chapter 2, we review the D1D5 system, including the gravity and CFT
descriptions. In Chapter 3, we show how to perturbatively relax the decoupling
limit in a general AdS-CFT setting. This allows one to compute the emission out
of the AdS/CFT into the asymptotic flat space. In Chapter 4, we apply that
formalism to some particular geometries, and exactly reproduce the emission
spectrum. These geometries are interpreted as fuzzball microstates of a black
hole, and the emission as the microscopic analogue of the Hawking radiation. In
Chapter 5, we discuss how to deform the D1D5 CFT off of its orbifold point. In
particular, we present full off-shell expressions for first-order corrections
to the CFT states. One can see how high-energy states can fragment into many
lower-energy states. In the conclusion, we discuss some opportunities for
future work.
