Dh25final final corrected[92]

It is often claimed that the special theory of relativity (STR) necessitates the block universe view, according to which all the events spread out in space-time are determinate, ‘fixed’ once and for all. After having briefly recalled the basic notions of STR (principle of relativity, constancy of the speed of light, relativity of simultaneity) (section 1), I will distinguish and discuss the different arguments taken from STR in favor of the block universe view: the ‘geometric argument’ (the spatialization of time) (section 2), the ‘becoming-argument’ (the loss of the becoming) (section 3), and the ‘determinateness-argument’ (the determinateness of the future) (section 4). Among these, I will focus in particular on the last argument, which can be summarized as follows: STR entails this puzzling consequence that any future event in a given inertial reference frame is already present or past in another inertial reference frame. Any future event is therefore already determinate. I will show that this argument (the “Rietdijk-Putnam argument”) contains a fallacy, and present several replies to it. My conclusion is that the notion of time in STR does not necessarily imply the block universe view; rather, it gives rise to a new ontology that are more complex but nevertheless consistent.

Disputatio, 2021

In the first part of the paper, we show that C&R's axioms generate the following dilemma. On the one hand, they could admit that truths about future contingents have no real ground in reality. To reject the requirement of grounding, however, goes against the intuitions of most philosophers concerning truth. On the other hand, C&R could give up bivalence for future contingents at the cost of making their temporal logic more complicated and presumably losing certain theorems. In the second part, we evaluate C&R's relativistic generalization of the growing block by discussing the various options that can be used to make relativity cohere with the growing block, and we illustrate the reasons why Stein's "pointy present" looks preferable to bow-tie presentism.

Relativity and the Dimensionality of the World, 2007

It is often said that the relativistic fusion of time with space rules out genuine change or "becoming". I offer the classical sequential growth models of causal set theory as counterexamples. 1. Can one hold a "four-dimensional" point of view and still maintain consistently that things really happen? Is a spacetime perspective compatible with the idea of "becoming"?

2010

Recent times have been very much focussed on the future. The election of Barack Obama in America was accompanied by a wave of optimism. The Global Financial Crisis and the challenge of Climate Change cause many to descend into pessimism. It is not whether our glass is half-empty or half-full that we worry about, but whether it will be empty or full. As philosophers, naturally, we want to illuminate such concerns, so that we might understand them better and subject them to rational scrutiny.

Philosophy and Foundations of Physics, 2006

Ever since Hermann Minkowski’s now infamous comments in 1908 concerning the proper way to view space-time, the debate has raged as to whether or not the universe should be viewed as a four-dimensional, unified whole wherein the past, present, and future are regarded as equally real or whether the views espoused by the possibilists, historicists, and presentists regarding the unreality of the future (and, for presentists, the past) are more accurate. Now, a century after Minkowski’s proposed block universe first sparked debate, we present a new, more conclusive argument in favor of the eternalism. Utilizing an argument based on the relativity of simultaneity in the tradition of Putnam and Rietdijk and explicit novel but reasonable assumptions as to the nature of reality, we argue that the past, present, and future should be treated as equally real, thus ruling that presentism and other theories of time that bestow special ontological status to the past, present, or future are untenable. Finally, we respond to our critics who suggest that: (1) there is no metaphysical difference between the positions of eternalism and presentism, (2) the present must be defined as the “here” as well as the “now”, or (3) presentism is correct and physicists’ current understanding of relativity is incomplete because it does not incorporate a preferred frame. We call response 1 deflationary since it purports to dissolve or deconstruct the age-old debate between the two views and response 2 compatibilist because it does nothing to alter special relativity (SR), arguing instead that SR unadorned has the resources to save presentism. Response 3 we will call incompatibilist because it adorns SR in some way in order to save presentism a la some sort of preferred frame. We show that neither 1 nor 2 can save presentism and 3 is not well motivated at this juncture except as an ad hoc device to refute eternalism.

2017

A.N. Prior’s Past, Present and Future [18] was published 50 years ago in 1967 and was clearly a milestone in the development of tense-logic. It is a mature and comprehensive presentation of the basic concepts, systems and issues in tense-logic. In addition it also contains a number of interesting ideas that later led to important further developments of the field. Past, Present and Future represents a culmination of Prior’s struggle with the problem of determinism (including his study of the tension between the doctrines of divine foreknowledge and human freedom). Prior’s study of the problem of determinism led him to a reconstruction of the famous DiodoreanMaster Argument which had for centuries been regarded as a strong argument in favour of determinism. In his further analysis of the problem, hemade extensive use of tense-logic and the idea of branching time. However, in Past, Present and Future Prior also stresses that time as such should not simply be understood in terms of bra...

2019

As a main challenge to the growing block theory (GBT), the epistemic objection is intended to show that GBT is untenable because it leads to the ignorance of the objective present. What is worse, extant solutions to this objection, the dead past view (DPV) and strong tense views (STV), are unsatisfactory on the ground that their semantic explanations of tensed statements undermine the purported semantic unity of GBT and thus make GBT collapse into a version of presentism. In contrast to extant solutions, I recommend growing blockists to adopt a new "biting the bullet" solution: They should accept the ignorance of the absolute present for the dual purpose of retaining GBT's semantic unity and theoretical independence. Moreover, I argue that ignorance is not a big loss for growing blockists: Although they lose the so-called "Moorean common advantage" over B-theorists and include some "deeply mysterious" and epistemically inaccessible fundamental posit in their ontology, growing blockists thereby protect the semantic unity of their theory and most of ordinary knowledge about B-relations between moments of time and their temporal locations. Theory choice, in essence, is a matter of balancing benefits and costs. I believe that versions of GBT which accept the ignorance of the objective present are indeed tenable intermediate positions in the philosophical debate about the nature of time, and they deserve serious considerations of B-theorists.

Ulrich Meyer’s book The Nature of Time uses tense logic to argue for a ‘modal’ view of time, which replaces substantial times (as in Newton’s Absolute Time) with ‘ersatz times’ constructed using conceptually basic tense operators. He also argues against Bertrand Russell’s relationist theory, in which times are classes of events, and against the idea that relativity compels the integration of time and space (called by Meyer the Inseparability Argument). I find fault with each of these negative arguments, as well as with Meyer’s purported reconstruction of empty spacetime from tense operators and substantial spatial points. I suggest that Meyer’s positive project is best conceived as an elimination of time in the mode of Julian Barbour's The End of Time.

The thesis provides a survey and analysis of three-dimensional and four- dimensional theories of time. These theories are considered both from the perspective of experienced time and of physical time. It is argued that experienced time is tensed and finite. It is further argued that physical time can be modeled by various theories, and that the choice of temporal theory is largely determined by the basic tenets of a particular theory of the external world. Arthur Prior‟s tense logic and U-calculus are presented, and it is shown that tense logic models tensed time, while the U-calculus models tenseless time. Further, it is seen that the U-calculus can be reduced to tense logic. Following the development of a general hybrid modal logic, a temporal hybrid modal logic is presented which is shown to model both tensed and tenseless time.