We analytically calculate the quasi-normal modes of various perturbations of
spacelike stretched and null warped AdS3​ black holes. From AdS/CFT
correspondence, these quasi-normal modes are expected to appear as the poles in
momentum space of retarded Green functions of dual operators in CFT at finite
temperature. We find that this is indeed the case, after taking into account of
the subtle identification of quantum numbers. The subtlety comes from the fact
that only after appropriate coordinate transformation the asymptotic geometries
of warped black holes are the same as the ones of warped AdS3​ spacetimes. We
show that in general the quasi-normal modes are in good agreement with the
prediction of the warped AdS/CFT correspondence, up to a constant factor. As a
byproduct, we compute the conformal dimensions of boundary operators dual to
the perturbations. Our result gives strong support to the conjectured warped
AdS/CFT correspondence.Comment: 26 pages; typos corrected, references added; more clarifications,
match the version to appear in JHE