Constraints on Braneworld Gravity Models from a Kinematic Limit on the Age of the Black Hole XTE J1118+480

In braneworld gravity models with a finite AdS curvature in the extra dimension, the AdS/CFT correspondence leads to a prediction for the lifetime of astrophysical black holes that is significantly smaller than the Hubble time, for asymptotic curvatures that are consistent with current experiments. Using the recent measurements of the position, three-dimensional spatial velocity, and mass of the black hole XTE J1118+480, I calculate a lower limit on its kinematic age of 11 Myr (95% confidence). This translates into an upper limit for the asymptotic AdS curvature in the extra dimensions of 0.08 mm, which significantly improves the limit obtained by table-top experiments of sub-mm gravity.Comment: 4 pages, to appear in the Physical Review Letter