The debate on the conventionality of simultaneity and the debate on the dimensionality of the world have been central in the philosophy of special relativity. The link between both debates however has rarely been explored. The purpose of this paper is to gauge what implications the former debate has for the latter. I show the situation to be much more subtle than was previously argued, and explain how the ontic versus epistemic distinction in the former debate impacts the latter. Despite (...) claims to the contrary, I conclude that special relativity leaves the debate on the dimensionality of the world underdetermined. (shrink)

This article proposes a “third way” in the philosophy of time beyond A-theory and the block universe, in which time is understood as a purely local phenomenon. It does so by starting with simple metaphysical assumptions about substances and their properties. Based on these assumptions, the notions of “before”, of change, and of time as local quantification of change can be derived non-circularly, i.e. without invoking temporal concepts. I then proceed to prove the irreversibility of local time by showing that (...) the propositional content of the local past cannot be changed, since this would imply a contradiction, whereas that of the future can. Time’s familiar asymmetric character, in particular the difference between the fixed past and the open or “branching” future, is therefore a non-illusory but purely local phenomenon. Such a model requires no past-present-future distinction valid for the entire cosmos, and is therefore consistent with special and general relativity. (shrink)

Presentism is, roughly, the metaphysical doctrine that maintains that whatever exists, exists in the present. The compatibility of presentism with the theories of special and general relativity was much debated in recent years. It has been argued that at least some versions of presentism are consistent with time-orientable models of general relativity. In this paper we confront the thesis of presentism with relativistic physics, in the strong gravitational limit where black holes are formed. We conclude that the presentist position is (...) at odds with the existence of black holes and other compact objects in the universe. A revision of the thesis is necessary, if it is intended to be consistent with the current scientific view of the universe. (shrink)

By considering situations from the paradox of the twins in relativity, it is shown that time passes at different rates along different world lines, answering some well-known objections. The best explanation for the different rates is that time indeed passes. If time along a world line is something with a rate, and a variable rate, then it is difficult to see it as merely a unique, invariant, monotonic parameter without any further explanation of what it is. Although it could, conceivably, (...) be explained by the flow of something, it is better explained by the passing of a point present, which faces the problem that there is no absolute simultaneity in special relativity so that the present for an object is confined to just that object. This raises problems about presentism, eternalism, simultaneity, and special relativity. These issues are addressed first by giving accounts of presentism and eternalism and then an account of existence and times for objects relative to world lines. Finally, an analogy between a world of relativistic objects and Leibniz’s ontology of monads. (shrink)

Traditionally one main emphasis of the quantum mechanical measurement theory is on the question how the pure state of the compound system 'measured system + measuring apparatus' is transformed into the 'mixture' of all possible results of that measurement, weighted with their probability: the so-called “disappearance of the interference terms”. It is argued in this note that in reality there is no such transformation, so that there is no need to account for such a transformation theoretically. _German_ Gewöhnlich liegt ein (...) Hauptgewicht der quantenmechanischen Messtheorie auf der Frage des Übergangs vom,reinen Fall' des Gesamtsystems,gemessenes System + Messgerät' in das,Gemenge' aus allen möglichen Messergebnissen, gewichtet mit ihren Wahrscheinlichkeiten: Das sog.,,Verschwinden der Interferenzterme“. In dieser Notiz wird die Meinung vertreten, dass es einen solchen Übergang faktisch nicht gibt, so dass es nicht notwendig ist, eine theoretische Erklärung für den Übergang zu geben. (shrink)

This essay offers a reaction to the recent resurgence of presentism in the philosophy of time. What is of particular interest in this renaissance is that a number of recent arguments supporting presentism are crafted in an untypically naturalistic vein, breathing new life into a metaphysics of time with a bad track record of co-habitation with modern physics. Against this trend, the present essay argues that the pressure on presentism exerted by special relativity and its core lesson of Lorentz symmetry (...) cannot easily be shirked. A categorization of presentist responses to this pressure is offered. As a case in point, I analyze a recent argument by Monton (2006) presenting a case for the compatibility of presentism with quantum gravity. Monton claims that this compatibility arises because there are quantum theories of gravity that use fixed foliations of spacetime and that such fixed foliations provide a natural home for a metaphysically robust notion of the present. A careful analysis leaves Monton's argument wanting. In sum, the prospects of presentism to be alleviated from the stress applied by fundamental physics are faint. (shrink)

The purpose of this paper is twofold: a) to explore the compatibility of Minkowski’s space-time representation of the Special theory of relativity with a dynamic conception of space-time; b) to locate its roots in invariant features - like entropic relations - of the propagation of signals in space-time. From its very beginning Minkowski’s four-dimensional space-time was associated with a static view of reality, e.g. a block universe. Einstein added his influential voice to this conception when he wrote: ‘From a “happening” (...) in three-dimensional space, physics becomes (…) an “existence” in the four-dimensional “world”.’ (Einstein, Relativity 1920, 122) Yet it is by no means clear that Minkowski himself was a believer in the block universe. In his 1908 Cologne lecture on ‘Space and Time’ he speaks of a four-dimensional physics but concedes that a ‘necessary’ time order can be established at every world point. Although the conception of the block universe has gained much currency, an alternative view has been in circulation since the 1910s according to which the trajectories of particles constitute histories in space-time. (Robb 1914, Cunningham 1915, Carathéodorys 1924, Schlick 1917, Reichenbach 1924). (shrink)

This essay introduces a formal structure to model the indeterminacy of the future in Einstein-Minkowski space-time. We consider a first-order language, supplemented with an operator for predicate-term negation, and defend the claim that such an operation provides an appropriate model for the indeterminacy of future contingents. In the final section, it is proved that given a language otherwise adequate to represent a physical theory, at least some of the predicates of that language are indeterminate when the future is not causally (...) determined by the present and the past. (shrink)

This chapter outlines a metaphysics of science in the sense of a naturalized metaphysics. It considers in the first place the interplay of physics and metaphysics in Newtonian mechanics, then goes into the issues for the metaphysics of time that relativity physics raises, shows that what one considers as the referent of quantum theory depends on metaphysical considerations and finally explains how the stance that one takes with respect to objective modality and laws of nature shapes the options that are (...) available for an ontology of quantum physics. In that way, this chapter seeks to make a case for a natural philosophy that treats physics and metaphysics as inseparable in the enquiry into the constitution of the world, there being neither a neo-positivist way of deducing metaphysics from the formalisms of physical theories, nor a neo-rationalist realm of investigation for metaphysics that is independent of physics. (shrink)

Privileged-perspective realism (PPR) is a version of metaphysical realism that takes certain irreducibly perspectival facts to be partly constitutive of reality. PPR asserts that there is a single metaphysically privileged standpoint from which these perspectival facts obtain. This chapter discusses several views that fall under the category of privileged-perspective realism. These include presentism, which is PPR about tensed facts, and non-multiverse interpretations of quantum mechanics, which the chapter argues, constitute PPR about world-indexed facts. Using the framework of the bird perspective (...) and the frog perspective, it argues that PPR views methodologically treat the frog perspective as metaphysically primary. This chapter considers case studies of metaphysical interpretations of special relativity and quantum mechanics in order to demonstrate that such motivations for PPR are non-naturalistic. Further, it considers psychological factors that motivate the appeal of PPR views and offers naturalistic explanations of why we should not expect them to produce an adequate metaphysics of science. (shrink)

This paper argues that the Einstein-Minkowski space-time of special relativity provides an adequate model for classical tense logic, including rigorous definitions of tensed becoming and of the logical priority of proper time. In addition, the extension of classical tense logic with an operator for predicate-term negation provides us with a framework for interpreting and defending the significance of future contingency in special relativity. The framework for future contingents developed here involves the dual falsehood of non-logical contraries, only one of which (...) becomes true. This has several methodological, metaphysical and physical advantages over the alternative traditional frameworks for handling future contingents. (shrink)

The kinematic consequences of special relativity can be expressed in three-dimensional language. Remarkably, this does not mean that, for making special relativity operational, positing a three-dimensional ontology is as good as positing the four-dimensional ontology. This is a singular limitation, whose nature is worth close inspection. In exploring it not just within a traditional, kinematic or geometric perspective but in its modern scientific context – i.e. as regards (1) causation, (2) localized observers that physics finds in nature and are not (...) mere short forms for reference frames, and (3) the semiosis they develop and use to make reference to distant present objects – this essay pursues two aims. First, to put on view that the block universe outlook, regarding the macroscopic-scale universe as a timelessly existing four-dimensional world each of whose diverse items is composed of temporal parts, despite its being ontologically incorrect is indeed the only one that is consistent with special relativity, whose calculations are correct. This is tantamount to point out that the special relativity's descriptions of the macrouniverse necessitate to portray time as a dimension, and moreover as an uncollapsed one; i.e., as a compass wherein mobility, in the vein of the translocative motion that may occur on every spatial dimension, ought to be at least conceivable. Second, to probe arguments defending that special relativity alone can resolve the debate on whether the extramental macroworld is three-dimensional or four-dimensional. In particular, since relativity's condition of possibility, namely the imposition on relativistic observers of describing at once past, present, and future states along the length of the observed moving entities, has been considered a proof that past and future components of real entities enjoy an unremitting mode of existence, the main argument probed in this paper is the one claiming that "if the world were three-dimensional, the kinematic consequences of special relativity and more importantly the experiments confirming them would be impossible." This is acknowledged as exact but it is remarked that, such imposition being a Kantian condition of possibility, it cannot reveal anything about what Kant called noumenon, i.e. extramentality. (shrink)