Live from/in Geneva (more details above):

Elena Castellani (University of Florence): Duality and emergence: the case of weak/strong duality

Abstract: The two notions of duality and emergence seem to be in an intriguing relation: on the one side, they seem to be closely connected, on the other side, they are clearly distinct —- perhaps even mutually exclusive? The key feature, in the case of duality, is the kind of equivalence that is entailed between the two theories (or the two descriptions of the same theory, in case of self-duality). In the case of emergence, the focus is rather on the aspect of novelty that the notion entails, and thus, apparently, on a lack of equivalence between the two theoretical descriptions. The dualities which are of great relevance in field and string theory, however, seem to be related to emergence: in many cases, the dual correspondence seems to give a form of emergence (new particles or new phenomena). How to combine these apparently contrasting features?

This talk is directly connected to the preceding talk by Sebastian de Haro discussing the relation between duality and emergence in the case of gauge/gravity duality (Geneva, 14.01.2016). Here, the same issue is discussed in another relevant duality case, that is, weak-strong duality or S-duality (as is usual to call it in the context of string theory) — a duality which has become a basic ingredient in field and string theories especially since the 1990s. In particular, the focus will be on the meaning of the dual correspondence between ‘elementary’ and ‘composite’ particles that this kind of duality apparently implies. At first sight, the correspondence could be interpreted as giving rise to new objects or a new way of looking at the same objects. The question is then how to intend this novelty feature given the symmetric character of the dual correspondence. The general aim is to explore whether and in which sense comparing duality and emergence can be a helpful exercise for the philosophical reflection on their meaning.

In terms of technical difficulty, this talk rates 3/5