Operator mixing in deformed D1D5 CFT and the OPE on the cover

Understand

We consider the D1D5 CFT near the orbifold point and develop methods for computing the mixing of untwisted operators to first order by using the OPE on the covering surface.

• We argue that the OPE on the cover encodes both the structure constants for the orbifold CFT and the explicit form of the mixing operators.
• We show this explicitly for some example operators.
• We start by considering a family of operators dual to supergravity modes, and show that the OPE implies that there is no shift in the anomalous dimension to first order, as expected.