Time in the Special Theory of Relativity

Abstract

Restricted to special relativity, this chapter observes that the most significant change in the concept of time is certainly the relativity of simultaneity. What events are simultaneous with some event for one observer are different from those that are simultaneous with respect to an object traveling in a different inertial frame. Many believe that this relativity can play a role in an argument for eternalism. This chapter critically surveys these arguments before taking on the implications of relativity for the metaphysics of time. It also tackles the conventionality of simultaneity. Many philosophers of science, especially during the early days of relativity, felt that simultaneity is not only relative but also conventional—there is a crucial element of choice in deciding what events are simultaneous for any other in a given inertial reference frame, so that there is no fact of the matter about what is simultaneous.

Neither Presentism nor Eternalism

“…Here I argue that Presentism and Eternalism are both unpalatable, but we are not forced to choose among them; there is a natural third possibility (see also [3][4][5][6]).…”

Being, Becoming and the Undivided Universe: A Dialogue Between Relational Blockworld and the Implicate Order Concerning the Unification of Relativity and Quantum Theory

“…In spite of the presumption of dynamism, those who want fundamental explanation in physics to be dynamical and those who want a world that evolves in time in some objective fashion, face well-known problems concerning: 1) the possible blockworld implications of relativity (both special and general) and 2) canonical QG, the quantization of a generally covariant classical theory leading to "frozen time." As for whether relativity (both special and general) implies a blockworld, there is much debate [2]. Regarding special relativity (SR), many of us have argued [3] that given certain widely held innocuous assumptions and the Minkoswski formulation, special relativity does indeed imply a blockworld.…”

“…Two basic reactions to this tension between blockworld and frozen time on the one hand and dynamism on the other are to either embrace the former and show that at least the appearances of dynamism, if not the substance, can be maintained with resources intrinsic to relativity or the particular QG scheme in question [2] [7], or reject the former whether conceptually or formally and attempt to construct a fundamental theory that has something definitively dynamical at bottom. The idea is to somehow make time or change fundamental in some way, as opposed to merely emergent as in the case of string theory or an illusion as in the case of Wheeler-Dewitt.…”

Chronogeometrical Determinism and the Local Present

“…5 In addition to this relativity of simultaneity, it has been argued in effect that planes at other angles can equally well, though perhaps not equally simply or conveniently, represent nows. I discuss this view, the conventionality of simultaneity, in the first half of Savitt (2011) Moreover, even were it the case that simultaneity and reality went hand in glove, the original argument would fail because simultaneity in Minkowski spacetime is no longer transitive in the way that the original argument requires. In Newtonian spacetimes the binary relation 'a is simultaneous with b' is transitive.…”