AdS_3/LCFT_2 - Correlators in New Massive Gravity

TL;DR

<3-5 sentence high-level summary>We address whether New Massive Gravity (NMG) at the AdS3 chiral point admits a dual logarithmic CFT (LCFT). The authors compute 2-point correlators via the AdS/CFT correspondence, identifying a spectrum that includes left, right, logarithmic, and flipped-logarithmic modes, and show that the left-right correlators vanish while the logarithmic sector reproduces the LCFT pattern with vanishing central charges $c_L=c_R=0$ and new anomalies $b_L=b_R = -\sigma\frac{12\ell}{G_N}$. The result parallels the chiral CTMG case and fixes the normalization of the LCFT data in terms of the sign $\sigma$ of the Einstein-Hilbert term. Positivity and stability considerations favor the $\sigma=-1$ choice, raising questions about unitarity and black hole thermodynamics, and motivating further study of higher-point functions and extensions to related gravity theories.

Abstract

We calculate 2-point correlators for New Massive Gravity at the chiral point and find that they behave precisely as those of a logarithmic conformal field theory, which is characterized in addition to the central charges c_L = c_R = 0 by `new anomalies' b_L = b_R = -σ\frac{12\ell}{G_N}, where σis the sign of the Einstein-Hilbert term, \ell the AdS radius and G_N Newton's constant.