Counting Giant Gravitons in AdS_3

Understand

We quantize the set of all quarter BPS brane probe solutions in global AdS_3 \times S^3 \times T^4/K3 found in arxiv:0709.1168 [hep-th].

• We show that, generically, these solutions give rise to states in discrete representations of the SL(2,R) WZW model on AdS_3.
• Our procedure provides us with a detailed description of the low energy 1/4 and 1/2 BPS sectors of string theory on this background.
• The 1/4 BPS partition function jumps as we move off the point in moduli space where the bulk theta angle and NS-NS fields vanish.