Entropy increase during physical processes for black holes in   Lanczos-Lovelock gravity
  We study quasi-stationary physical process for black holes within the context of Lanczos-Lovelock gravity. We show that the Wald entropy of stationary black holes in Lanczos-Lovelock gravity monotonically increases for quasi-stationary physical processes in which the horizon is perturbed by the accretion of positive energy matter and the black hole ultimately settles down to a stationary state. This result reinforces the physical interpretation of Wald entropy for Lanczos-Lovelock models and takes a step towards proving the analogue of the black hole area increase-theorem in a wider class of gravitational theories. 
Sanved Kolekar, T. Padmanabhan and Sudipta Sarkar
gr-qc astro-ph.CO hep-th