Abstract

The observed properties of debris discs are seen to change with stellar age in a manner indicative of the discs’ evolution. The majority of the observed trends agree with what would be expected from the steady state collisional evolution of planetesimal belts formed in the protoplanetary disc. However, there remains uncertainty as to how debris discs are stirred, and about the role of stochastic processes (due to either massive collisions or planetary system instability) in their evolution. More generally the study of debris discs offers a unique opportunity to probe how planetesimals and planetary systems form and evolve. This talk will review our current understanding of the theory of debris disc evolution, due to both collisional processes within the disc, and due to the dynamics of its interaction with a (typically unseen) planetary system.