Talk by Lorenz Eberhardt

Tensionless strings on AdS3

Abstract:
String theory on AdS3 backgrounds have long held out hope to explore the tensionless limit of string theory. In this talk, I would like to make this idea more explicit. I will discuss AdS3xS3xM4 backgrounds with pure NS-NS flux for M4=T4, K3 or S3xS1 and show that the background with the lowest amount of NS-NS flux (`k=1') is dual to the large N limit of the symmetric product orbifold of M4. I will explain how the worldsheet theory can be consistently defined for k=1 by employing the hybrid formalism. The representation theory on the worldsheet for k=1 becomes far more restrictive than in the generic case, in particular all short string solutions and the continuum of long strings disappear, only the lowest energy long string solution is still allowed. This proposal therefore affords a tractable worldsheet description of a tensionless limit in string theory, for which the dual CFT is also explicitly known.