In this talk I will present a new way of visualizing and studying a binary black hole coalescence. Instead of employing global event horizons, this method is based on the central ingredient of the singularity theorems of general relativity, namely trapped surfaces. I show how two initially disjoint marginally trapped surfaces merge to form a single final black hole.
Moreover, this study uncovers a previously unknown phenomenon, namely the formation of marginally trapped surfaces with self-intersections.