From Parallel Universes to Possible Worlds : Ontological Pluralism in Physics, Narratology and Narrative This essay explores how theoretical physics, narratology and narrative itself deal with the idea that reality consists of a plurality of worlds. In physics, the existence of parallel universes has been postulated on the cosmic level to describe what lies on the other side of black holes, and on the level of subatomic particles to avoid the paradoxes of quantum mechanics. In narratology, the philosophical idea of a plurality of possible worlds and the contrast between the actual and the possible provides a model of the cognitive pattern into which readers organize information in order to interpret it as a story. But the many-worlds interpretation of physics and the possible worlds (PW) model of narrative differ in their conception of the ontological status of the multiple worlds: in physics they are all actual, while narrative theory stresses the contrast between actuality and mere possibility. This does not mean that the PW model is incompatible with the many-worlds cosmology proposed by physics: faced with a narrative that presents multiple realities as existing objectively, the theory would simply claim that the actual domain is made of a number of different worlds, and that within each of these parts, the distinction actual-non-actual repeats itself. The last section of the essay explores what it takes for a narrative to impose a many-worlds cosmology, distinguishing these narratives from other texts that present contradictory versions of facts, and situating them with respect to three types of story common in fantasy and science fiction: the narrative of transworld exploration, the narrative of alternate history, and the time travel narrative. Return Diagramming Narrative The use of diagrams as a tool of narrative analysis is a fundamentally semiotic project whose origins can be traced back to the emphasis placed by the structuralist movement on the synchronic systems that underlie signification. Defining diagrams as a spatial presentation of information which conveys meanings that could not be expressed in the linear form of a text, a list, or a formal coding system, this paper focuses on attempts to represent individual narrative plots, as opposed to diagrams that model a universal narrative structure or discourse phenomena. Through the analysis of diagrams relating to three aspects of plot—time, space, and mind—I argue that graphic representations are not merely a tool for representing narratological knowledge, but an important way to produce this knowledge. At their very best, they can be the seed of a new theory. Return