Does General Relativity Highlight Necessary Connections in Nature?

Abstract

The dynamics of general relativity is encoded in a set of ten differential equations, the so-called Einstein field equations. It is usually believed that Einstein's equations represent a physical law describing the coupling of spacetime with material fields. However, just six of these equations actually describe the coupling mechanism: the remaining four represent a set of differential relations known as Bianchi identities. The paper discusses the physical role that the Bianchi identities play in general relativity, and investigates whether these identities -- qua part of a physical law -- highlight some kind of a posteriori necessity in a Kripkean sense. The inquiry shows that general relativistic physics has an interesting bearing on the debate about the metaphysics of the laws of nature.

29 pages, 2 figures, accepted for publication in Synthese

References in corpus (5)

• The Parameterized Post-Friedmann Framework for Theories of Modified Gravity: Concepts, Formalism and Examples
• Some remarks on the notions of general covariance and background independence
• A general theory of linear cosmological perturbations: bimetric theories
• Leibnizian relationalism for general relativistic physics
• Dependence Relations in General Relativity