Space and time ontology: new models for new physics

In one of professor Nickel's papers [NICKEL 2006], he proposes a model for movement - and in general, for change - in which each instant in time (characterized as the set of real numbers) is assigned to one point in a configuration space. As much as this model seems to intuitively fit to our experience, it implies a number of assumptions about the nature of space and time that are interesting to explore. During the debate session I mentioned the timeless physics developed by Juian Barbour [BARBOUR 1999] as an example of a different perspective. This paper reviews not only this concept but also other similarly provocative ideas that might prove useful for improving our understanding of the universe. Prior to this, the relevance of the philosophy of space and time will be briefly outlined and its history reviewed to provide some background for the discussed models. Finally, an approach where space and time are only defined by convention will be considered.