1205.4185 (Shih-Hao Ho et al.)

Anti-de Sitter Space as Topological Insulator and Holography    [PDF]

Shih-Hao Ho, Feng-Li Lin

We argue that the Anti-de Sitter (AdS) space can be thought as a topological insulator with a co-dimensional one defect living at the UV boundary. Combining the bulk/edge correspondence for the topological insulators and the AdS/CFT correspondence, the fermionic topological phases for the dual conformal field theories (CFTs) can then be classified in the same way as classifying the topological phases of the massive free fermions in the co-dimensional one higher Minkowski spaces. The latter can then be obtained in Kitaev's framework of the K-theory analysis in classifying the topological insulators/superconductors. Our framework provides a way of classifying the symmetry-protected topologically ordered phases for the strongly interacting gapless systems, of which the classification is intractable in the context of strongly correlated condensed matters devised mainly for gapped systems.

View original: http://arxiv.org/abs/1205.4185