Self-locating belief in big worlds: Cosmology's missing link to observation

Abstract

The article explains why it is not possible for observers in a large, homogeneous, and isotropic universe to determine their location and orientation without referring to distant objects outside their causal past. Lacking the ability to pinpoint one’s place in the universe has fundamental implications for the prospects of a self-locating science, that is, a science based on observation alone. It is shown that to establish local, self-locating belief in the theory, it is necessary to combine observational results with indifference principles that have a de se (i.e. measure-theoretic) character. The resources required for self-locating belief are thereby shown to include not only the ability to observe local phenomena but also the ability to evaluate probabilities over propositions which refer to sets of physically disconnected regions of spacetime. – AI-generated abstract.