UNC-CH STRING THEORY SEMINAR
Dr. David Berenstein, UC Santa Barbara
“Emergent Geometry: Seeing Further from the Shoulders of Giants”
The gauge/gravity duality has given us an equivalence between theories of gravity in higher dimensions and ordinary field theories in low dimensions. An important question is: where do the extra dimensions in the gravity theory come from, and when are they geometric? I will show that for some special conformal field theories closely related to N=4 SYM, one can understand this issue by studying a special class of states in field theory where the problem reduces to computing the planar anomalous dimension of the corresponding states to all orders in perturbation theory. At first non-trivial order this gives rise to an interesting open spin chain problem with unconventional boundary conditions which is solvable for the ground state.
These states in the gravity dual can be interpreted as strings suspended between giant gravitons. Giant gravitons are particular D-brane states in the higher dimensional geometry, which in field theory are similar to baryons. I will then show how one can read the sizes of cycles and other geometric features, by understanding the spectrum of such states.