On the conditioned exit measures of super Brownian motion

Research paper by Thomas S. Salisbury, John Verzani

Indexed on: 01 Sep '99Published on: 01 Sep '99Published in: Probability Theory and Related Fields


In this paper we present a martingale related to the exit measures of super Brownian motion. By changing measure with this martingale in the canonical way we have a new process associated with the conditioned exit measure. This measure is shown to be identical to a measure generated by a non-homogeneous branching particle system with immigration of mass. An application is given to the problem of conditioning the exit measure to hit a number of specified points on the boundary of a domain. The results are similar in flavor to the “immortal particle” picture of conditioned super Brownian motion but more general, as the change of measure is given by a martingale which need not arise from a single harmonic function.