High Energy Physics

The AdS/CFT correspondence provides a remarkably useful tool
for asking questions in quantum gravity, as it formulates a theory of
quantum gravity in terms of an ordinary non-gravitational quantum field
theory.  Fruitfully exploiting this correspondence therefore requires
understanding how to translate the language of CFT into gravity; a key
insight that has emerged over the past decade is that the entanglement
structure of the CFT must be intimately tied to the emergence of the
gravitational dual (when a classical geometric picture even exists).  In
my talk, I'll review what is currently known about this emergence
(so-called bulk reconstruction), and then discuss some recent results on
precisely how the entanglement of the CFT fixes the geometry on the
gravitational side.  I'll conclude with some open directions, notably
how the result I'll present is amenable to incorporating quantum
corrections.

Black Hole Entropy is a well established concept and arises naturally once one realises that black holes are characterised by a temperature. Boltzmann established that entropy can be regarded as the logarithm of the density of states function. However, black hole uniqueness theorems appeared to indicate that black holes have no hair. I will describe a loophole in the no-hair theorems and how black holes can have an infinite set of charges related to "large" gauge transformations. I will then use these ideas to show that on sections of the horizon there is a holographic conformal field theory. The temperature of this conformal theory means that it has a statistical entropy that reproduces the Hawking formula. The implications of this for the black hole information paradox will be briefly described.