Recorded 18 November 2021. Juan Calderon-Bustillo of the University of Santiago de Compostela presents "The challenge of characterising high-mass compact mergers: the case of GW190521" at IPAM's Workshop III: Source inference and parameter estimation in Gravitational Wave Astronomy. Abstract: Gravitational-wave signals from high-mass compact binary coalescences mostly display the merger and ringdown portions of the process, barely providing any information about the properties of the initial objects. Consequently, the interpretation of the source is less robust than that of lighter mergers displaying long inspiral signals. In this talk I will discuss the role of prior choices in Bayesian inference of the properties of high-mass mergers, using the controversial GW190521 as a driving example. Among other topics, I will discuss the possibilities that this signal could have been sourced by an eccentric black-hole merger, by a high-mass ratio merger and even by exotic compact objects known as boson stars. Learn more online at: http://www.ipam.ucla.edu/programs/workshops/workshop-iii-source-inference-and-parameter-estimation-in-gravitational-wave-astronomy/?tab=schedule