Flavor anomalies from asymptotically safe gravity

Abstract

We use the framework of asymptotically safe quantum gravity to derive predictions for scalar leptoquark solutions to the $b\to s$ and $b\to c$ flavor anomalies. The presence of an interactive UV fixed point in the system of gauge and Yukawa couplings imposes a set of boundary conditions at the Planck scale, which allows one to determine low-energy values of the leptoquark Yukawa matrix elements. As a consequence, the allowed leptoquark mass range can be significantly narrowed down. We find that a consistent gravity-driven solution to the $b\to s$ anomalies predicts a leptoquark with the mass of 4-7 TeV, entirely within the reach of a future hadron-hadron collider with $\sqrt{s}=100$ TeV. Conversely, in the case of the $b\to c$ anomalies the asymptotically safe gravity framework predicts a leptoquark mass at the edge of the current LHC bounds. Complementary signatures appear in flavor observables, namely the (semi)leptonic decays of B and D mesons and kaons.

Comments: 39 pages, 6 figures. Added discussion of a trans-Planckian IR fixed point in Section 3.1. Added scenarios of type FPc, corresponding to Gaussian fixed points of the NP couplings. References added