T T ¯ and LST

It was recently shown that the theory obtained by deforming a general two dimensional conformal theory by the irrelevant operator TT¯ is solvable. In the context of holography, a large class of such theories can be obtained by studying string theory on AdS₃. We show that a certain single trace TT¯ deformation of the boundary CFT₂ gives rise in the bulk to string theory in a background that interpolates between AdS₃ in the IR and a linear dilaton spacetime in the UV, i.e. to a two dimensional vacuum of Little String Theory. This construction provides holographic duals for a large class of vacua of string theory in asymptotically linear dilaton spacetimes, and sheds light on the UV behavior of TT¯ deformed CFT₂. It may provide a step towards holography in flat spacetime.