The concept of a time-relative interest is introduced by Jeff McMahan to solve certain puzzles about the badness of death. Some people (e.g. McMahan and David DeGrazia) believe that this concept can also be used to show that abortion is permissible. In this paper, I first argue that if the Time-Relative Interest Account permits abortion, then it would also permit infanticide.

Don Marquis has argued most abortions are immoral, for the same reason that killing you or me is immoral: abortion deprives the fetus of a valuable future. Call this account the FLOA. A rival account is Jeff McMahan’s, time-relative interest account of the wrongness of killing. According to this account, an act of killing is wrong to the extent that it deprives the victim of future value and the relation of psychological unity would have held between the victim (...) at the time of death and herself at a later time if she had lived. The TRIA supposedly has two chief advantages over Marquis’s FLOA. First, unlike the FLOA, the TRIA does not rely on the controversial thesis that identity is what matters in survival. Second, the TRIA yields more plausible verdicts about cases. Proponents of the TRIA use the account to argue that abortion is generally permissible, because there would be little to no psychological unity between the fetus and later selves if it lived. I argue that advocates of the TRIA have failed to establish its superiority to the FLOA, for two reasons. First, the two views are on a par with respect to the thesis that identity is what matters in survival. Second, Marquis’s FLOA does not yield the counterintuitive implications about cases that advocates of the TRIA have attributed to it, and the TRIA yields its own share of implausible judgments about cases. (shrink)

Regarding the sinking lifeboat scenario involving several human beings and a dog, nearly everyone agrees that it is right to sacrifice the dog. I suggest that the best explanation for this considered judgment, an explanation that appears to time-relative interests, contains a key insight about prudential value. This insight, I argue, also provides perhaps the most promising reply to the future-like-ours argument, which is widely regarded as the strongest moral argument against abortion. Providing a solution to a longstanding (...) puzzle in value theory across species while illuminating the morality of abortion, the time-relative interest account proves worthy of sustained theoretical attention. (shrink)

Greg Bognar has recently offered a prioritarian justification for ‘fair innings’ distributive principles that would ration access to healthcare on the basis of patients' age. In this article, I agree that Bognar's principle is among the strongest arguments for age-based rationing. However, I argue that this position is incomplete because of the possibility of ‘time-relative' egalitarian principles that could complement the kind of lifetime egalitarianism that Bognar adopts. After outlining Bognar's position, and explaining the attraction of time- (...) class='Hi'>relative egalitarianism, I suggest various ways in which these two kinds of principle could interact. Since various options have very different implications for age-based rationing, proponents of such a rationing scheme must take a position on time-relative egalitarianism to complement a lifetime prioritarian view like Bognar's. (shrink)

Jeff McMahan appeals to what he calls the “Time-relative Interest Account of the Wrongness of Killing ” to explain the wrongness of killing individuals who are conscious but not autonomous. On this account, the wrongness of such killing depends on the victim’s interest in his or her future, and this interest, in turn, depends on two things: the goods that would have accrued to the victim in the future; and the strength of the prudential relations obtaining between the (...) victim at the time of the killing and at the times these goods would have accrued to him or her. More precisely, when assessing this interest, future goods should be discounted to reflect reductions in the strength of such relations. Against McMahan’s account I argue that it relies on an implausible “actualist” view of the moral importance of interests according to which satisfactions of future interests only have moral significance if they are satisfactions of actual interests. More precisely, I aim to show that the Time-relative Interest Account does not have the implications for the morality of killing that McMahan takes it to have, and implies, implausibly, that certain interest satisfactions which seem to be morally significant are morally insignificant because they are not satisfactions of actual interests. (shrink)

According to John Martin Fischer and Anthony Brueckner’s unique version of the deprivation approach to accounting for death’s badness, it is rational for us to have asymmetric attitudes toward prenatal and posthumous nonexistence. In previous work, I have defended this approach against a criticism raised by Jens Johansson by attempting to show that Johansson’s criticism relies on an example that is incoherent. Recently, Duncan Purves has argued that my defense reveals an incoherence not only in Johansson’s example but also in (...) Fischer and Brueckner’s approach itself. Here I argue that by paying special attention to a certain feature of Fischer and Brueckner’s approach, we can dispense of not only Johansson’s criticism but also of Purves’s objection to Fischer and Brueckner’s approach. (shrink)

It has been shown that the Lorentz transformations in special relativity can be derived in terms of the principle of relativity and certain properties of space and time such as homogeneity. In this paper, we argue that the free Schrodinger equation in quantum mechanics may also be regarded as a consequence of the homogeneity of space and time and the principle of relativity when assuming linearity of time evolution.

Sellars once wrote that “‘the problem of time’ is rivaled only by the ‘mind-body problem’ in the extent to which it inexorably brings into play all the major concerns of philosophy”. Considering that time plays a major role both in our inner life and in the description of the outer world, one could suggest that two problems are deeply related: our progress in understanding bits of the problem of time might shed light into the mind-body problem and (...) vice versa. In this paper, I will test the plausibility of this suggestion, by focusing on a fundamental aspect of the relationship between the ‘time of physics’ and the ‘time of mind’, namely the problem of their compatibility. (shrink)

The substance view is an account of personhood that regards all human beings as possessing instrinsic value and moral status equivalent to that of an adult human being. Consequently, substance view proponents typically regard abortion as impermissible in most circumstances. The substance view, however, has difficulty accounting for certain intuitions regarding the badness of death for embryos and fetuses, and the wrongness of killing them. Jeff McMahan’s time-relative interest account is designed to cater for such intuitions, and so (...) I present a proposal for strengthening the substance view by incorporating McMahan’s account – the Dual-Aspect Account of the morality of killing. I show that it resolves some important issues for the substance view while preserving its central premise of moral equality for all human beings. I then compare the Dual-Aspect Account with McMahan’s Two-Tiered Account of the morality of killing, which he derives from his time-relative interest account. (shrink)

Physical Relativity explores the nature of the distinction at the heart of Einstein's 1905 formulation of his special theory of relativity: that between kinematics and dynamics. Einstein himself became increasingly uncomfortable with this distinction, and with the limitations of what he called the 'principle theory' approach inspired by the logic of thermodynamics. A handful of physicists and philosophers have over the last century likewise expressed doubts about Einstein's treatment of the relativistic behaviour of rigid bodies and clocks in motion in (...) the kinematical part of his great paper, and suggested that the dynamical understanding of length contraction and time dilation intimated by the immediate precursors of Einstein is more fundamental. Harvey Brown both examines and extends these arguments, after giving a careful analysis of key features of the pre-history of relativity theory. He argues furthermore that the geometrization of the theory by Minkowski in 1908 brought illumination, but not a causal explanation of relativistic effects. Finally, Brown tries to show that the dynamical interpretation of special relativity defended in the book is consistent with the role this theory must play as a limiting case of Einstein's 1915 theory of gravity: the general theory of relativity.Appearing in the centennial year of Einstein's celebrated paper on special relativity, Physical Relativity is an unusual, critical examination of the way Einstein formulated his theory. It also examines in detail certain specific historical and conceptual issues that have long given rise to debate in both special and general relativity theory, such as the conventionality of simultaneity, the principle of general covariance, and the consistency or otherwise of the special theory with quantum mechanics. Harvey Brown' s new interpretation of relativity theory will interest anyone working on these central topics in modern physics. (shrink)

This chapter contains sections titled: * What is Relative Timelessness? * The Biblical Witness * Problems with Timeless Eternity * Timelessness Sans Creation * Notes * Bibliography.

According to a widespread view, Einstein’s definition of time in his special relativity is founded on the positivist verification principle. The present paper challenges this received outlook. It shall be argued that Einstein’s position on the concept of time, to wit, simultaneity, is best understood as a mitigated version of concept empiricism. He contrasts his position to Newton’s absolutist and Kant’s transcendental arguments, and in part sides with Hume’s and Mach’s empiricist arguments. Nevertheless, Einstein worked out a concept (...) empiricism that is considerably more moderate than what we find in the preceding empiricist tradition and early logical positivism. He did not think that the origin of concepts is in observations, but in conventions, and he also maintained a realist ontology of physical events, which he thought is necessary for his theory. Consequently, his philosophy of time in special relativity is not couched in terms of an anti-metaphysical verificationism. (shrink)

This article provides a non-technical overview of the conflict between the special theory of relativity and the dynamic theories of time. The chief argument against dynamic theories of time from relativistic mechanics is presented. The space of current responses to that argument is subsequently mapped.

Is the objective passage of time compatible with relativistic physics? There are two easy routes to an affirmative answer: (1) provide a deflationary analysis of passage compatible with the block universe, or (2) argue that a privileged global present is compatible with relativity. (1) does not take passage seriously. (2) does not take relativity seriously. This paper is concerned with the viability of views that seek to take both passage and relativity seriously. The investigation proceeds by considering how traditional (...) A-theoretic conceptions of passage might be generalized to relativistic space-times without incorporating a privileged global present. I argue that the most promising position marries the idea that open possibilities for the future are settled as time passes with a ‘non-standard’ interpretation of the relevant formal models. (shrink)

When addressing the notion of proper time in the theory of relativity, it is usually taken for granted that the time read by an accelerated clock is given by the Minkowski proper time. However, there are authors like Harvey Brown that consider necessary an extra assumption to arrive at this result, the so-called clock hypothesis. In opposition to Brown, Richard TW Arthur takes the clock hypothesis to be already implicit in the theory. In this paper I will (...) present a view different from these authors by taking into account Einstein’s notion of natural clock and showing its relevance to the debate. (shrink)

The larger project of which this volume forms part is an attempt to craft a coherent doctrine of divine eternity and God's relationship to time.

The aim of this book is to give an account of Einstein's work without introducing anything very technical in the way of mathematics, physics, or philosophy.

N. Maxwell (1985) has claimed that special relativity and "probabilism" are incompatible; "probabilism" he defines as the doctrine that "the universe is such that, at any instant, there is only one past but many alternative possible futures". Thus defined, the doctrine is evidently prerelativistic as it depends on the notion of a universal instant of the universe. In this note I show, however, that there is a straightforward relativistic generalization, and that therefore Maxwell's conclusion that the special theory of relativity (...) should be amended is unwarranted. I leave open the question whether or not probabilism (or the related doctrine of the flow of time) is true, but argue that the special theory of relativity has no fundamental significance for this question. (shrink)

In the first part of this contribution, we review the development of the theory of scale relativity and its geometric framework constructed in terms of a fractal and nondifferentiable continuous space-time. This theory leads (i) to a generalization of possible physically relevant fractal laws, written as partial differential equation acting in the space of scales, and (ii) to a new geometric foundation of quantum mechanics and gauge field theories and their possible generalisations. In the second part, we discuss some (...) examples of application of the theory to various sciences, in particular in cases when the theoretical predictions have been validated by new or updated observational and experimental data. This includes predictions in physics and cosmology (value of the QCD coupling and of the cosmological constant), to astrophysics and gravitational structure formation (distances of extrasolar planets to their stars, of Kuiper belt objects, value of solar and solar-like star cycles), to sciences of life (log-periodic law for species punctuated evolution, human development and society evolution), to Earth sciences (log-periodic deceleration of the rate of California earthquakes and of Sichuan earthquake replicas, critical law for the arctic sea ice extent) and tentative applications to systems biology. (shrink)

"--Brian Greene, Columbia University "This book includes material that is intellectually innovative and comes as a surprise even to specialists in the field.

In the transition to Einstein’s theory of Special Relativity (SR), certain concepts that had previously been thought to be univocal or absolute properties of systems turn out not to be. For instance, mass bifurcates into (i) the relativistically invariant proper mass m0, and (ii) the mass relative to an inertial frame in which it is moving at a speed v = βc, its relative mass m, whose quantity is a factor γ = (1 – β2) -1/2 times the (...) proper mass, m = γm0. (shrink)

I argue that truth is relative (in the sense recently defended by some prominent analytical philosophers) by focusing on some semantic issues raised by Einstein's theory of relativity together with our ordinary attributions of truth.

Two radically different views about time are possible. According to the first, the universe is three dimensional. It has a past and a future, but that does not mean it is spread out in time as it is spread out in the three dimensions of space. This view requires that there is an unambiguous, absolute, cosmic-wide "now" at each instant. According to the second view about time, the universe is four dimensional. It is spread out in both (...) space and time - in space-time in short. Special and general relativity rule out the first view. There is, according to relativity theory, no such thing as an unambiguous, absolute cosmic-wide "now" at each instant. However, we have every reason to hold that both special and general relativity are false. Not only does the historical record tell us that physics advances from one false theory to another. Furthermore, elsewhere I have shown that we must interpret physics as having established physicalism - in so far as physics can ever establish anything theoretical. Physicalism, here, is to be interpreted as the thesis that the universe is such that some unified "theory of everything" is true. Granted physicalism, it follows immediately that any physical theory that is about a restricted range of phenomena only, cannot be true, whatever its empirical success may be. It follows that both special and general relativity are false. This does not mean of course that the implication of these two theories that there is no unambiguous cosmic-wide "now" at each instant is false. It still may be the case that the first view of time, indicated at the outset, is false. Are there grounds for holding that an unambiguous cosmic-wide "now" does exist, despite special and general relativity, both of which imply that it does not exist? There are such grounds. Elsewhere I have argued that, in order to solve the quantum wave/particle problem and make sense of the quantum domain we need to interpret quantum theory as a fundamentally probabilistic theory, a theory which specifies how quantum entities - electrons, photons, atoms - interact with one another probabilistically. It is conceivable that this is correct, and the ultimate laws of the universe are probabilistic in character. If so, probabilistic transitions could define unambiguous, absolute cosmic-wide "nows" at each instant. It is entirely unsurprising that special and general relativity have nothing to say about the matter. Both theories are pre-quantum mechanical, classical theories, and general relativity in particular is deterministic. The universe may indeed be three dimensional, with a past and a future, but not spread out in four dimensional space-time, despite the fact that relativity theories appear to rule this out. These considerations, finally, have implications for views about the arrow of time and free will. (shrink)

B- theorists frequently argue that the A- theoretic views are incompatible with the Special Theory of Relativity (STR) and that this is a problem for the A- theoretic views. however, the B- theory needs to be revised in light of implications of STR. in particular, it follows from STR that some events stand in genuine temporal relations to each other while others do not. Consequently, there isn’t a single temporal order of all events. instead, there are multiple B- series. Some (...) B- theorists defend a view of the passage of time according to which passage is simply temporal succession. This paper argues that, in Minkowski spacetime, time passes in each of the multiple B- series, but there is no passage spanning across all events because some events stand in no genuine temporal relations to each other. (shrink)

In General Relativity in Hamiltonian form, change has seemed to be missing, defined only asymptotically, or otherwise obscured at best, because the Hamiltonian is a sum of first-class constraints and a boundary term and thus supposedly generates gauge transformations. Attention to the gauge generator G of Rosenfeld, Anderson, Bergmann, Castellani et al., a specially _tuned sum_ of first-class constraints, facilitates seeing that a solitary first-class constraint in fact generates not a gauge transformation, but a bad physical change in electromagnetism or (...) General Relativity. The change spoils the Lagrangian constraints, Gauss's law or the Gauss-Codazzi relations describing embedding of space into space-time, in terms of the physically relevant velocities rather than auxiliary canonical momenta. But the resemblance between the gauge generator G and the Hamiltonian H leaves still unclear where objective change is in GR. Insistence on Hamiltonian-Lagrangian equivalence, a theme emphasized by Castellani, Sugano, Pons, Salisbury, Shepley and Sundermeyer among others, holds the key. Taking objective change to be ineliminable time dependence, one recalls that there is change in vacuum GR just in case there is no time-like vector field xi^a satisfying Killing's equation L_xi g_mn=0, because then there exists no coordinate system such that everything is independent of time. Throwing away the spatial dependence of GR for convenience, one finds explicitly that the time evolution from Hamilton's equations is real change just when there is no time-like Killing vector. The inclusion of a massive scalar field is simple. No obstruction is expected in including spatial dependence and coupling more general matter fields. Hence change is real and local even in the Hamiltonian formalism. The considerations here resolve the Earman-Maudlin standoff over change in Hamiltonian General Relativity: the Hamiltonian formalism is helpful, and, suitably reformed, it does not have absurd consequences for change and observables. Hence the classical problem of time is resolved. The Lagrangian-equivalent Hamiltonian analysis of change in General Relativity is compared to Belot and Earman's treatment. The more serious quantum problem of time, however, is not automatically resolved due to issues of quantum constraint imposition. (shrink)

This volume offers an integrated understanding of how the theory of general relativity gained momentum after Einstein had formulated it in 1915. Chapters focus on the early reception of the theory in physics and philosophy and on the systematic questions that emerged shortly after Einstein's momentous discovery. They are written by physicists, historians of science, and philosophers, and were originally presented at the conference titled Thinking About Space and Time: 100 Years of Applying and Interpreting General Relativity, held at (...) the University of Bern from September 12-14, 2017. By establishing the historical context first, and then moving into more philosophical chapters, this volume will provide readers with a more complete understanding of early applications of general relativity and of related philosophical issues. Because the chapters are often cross-disciplinary, they cover a wide variety of topics related to the general theory of relativity. These include: Heuristics used in the discovery of general relativity Mach's Principle The structure of Einstein's theory Cosmology and the Einstein world Stability of cosmological models The metaphysical nature of spacetime The relationship between spacetime and dynamics The Geodesic Principle Symmetries Thinking About Space and Time will be a valuable resource for historians of science and philosophers who seek a deeper knowledge of the uses of general relativity, as well as for physicists and mathematicians interested in exploring the wider historical and philosophical context of Einstein's theory. (shrink)

_Time_'s 'Man of the Century', Albert Einstein is the unquestioned founder of modern physics. His theory of relativity is the most important scientific idea of the modern era. In this short book Einstein explains, using the minimum of mathematical terms, the basic ideas and principles of the theory which has shaped the world we live in today. Unsurpassed by any subsequent books on relativity, this remains the most popular and useful exposition of Einstein's immense contribution to human knowledge.

In this paper I try to sort out a tangle of issues regarding time, inertia, proper time and the so-called “clock hypothesis” raised by Harvey Brown's discussion of them in his recent book, Physical Relativity. I attempt to clarify the connection between time and inertia, as well as the deficiencies in Newton's “derivation” of Corollary 5, by giving a group theoretic treatment original with J.-P. Provost. This shows how both the Galilei and Lorentz transformations may be derived (...) from the relativity principle on the basis of certain elementary assumptions regarding time. I then reflect on the implications of this derivation for understanding proper time and the clock hypothesis. (shrink)

In this essay I address the issue of whether Einstein's Special Theory of Relativity counts against a tensed or "A-series" understanding of time. Though this debate is an old one, it continues to be lively with many prominent authors recently arguing that a genuine A-series is compatible with a relativistic world view. My aim in what follows is to outline why Special Relativity is thought to count against a tensed understanding of time and then to address the philosophical (...) attempts to reconcile the two theories. I conclude that while modern physics on its own does not rule out the possibility of a real A-series, the combination of Einstein's theory and the philosophical arguments against tense is decisive. The upshot is that the tenseless or "B-series" view of time is the best one. (shrink)

McTaggart distinguished two conceptions of time: the A-series, according to which events are either past, present or future; and the B-series, according to which events are merely earlier or later than other events. Elsewhere, I have argued that these two views, ostensibly about the nature of time, need to be reinterpreted as two views about the nature of the universe. According to the so-called A-theory, the universe is three dimensional, with a past and future; according to the B-theory, (...) the universe is four dimensional. Given special relativity (SR), we are obliged, it seems, to accept (a modified version of) the B-series, four dimensional view, and reject the A-series, three dimensional view, because SR denies that there is a privileged, instantaneous cosmic "now" which seems to be required by the A-theory. Whether this is correct or not, it is important to remember that the fundamental problem, here, is not "What does SR imply?", but rather "What is the best guess about the ultimate nature of the universe in the light of current theoretical knowledge in physics?". In order to know how to answer this question, we need to have some inkling as to how the correct theory of quantum gravity incorporates quantum theory, probability and time. This is, at present, an entirely open question. String theory, or M-theory, seems to evade the issue, and other approaches to quantum gravity seem equally evasive. However, if probabilism is a fundamental feature of ultimate physical reality, then it may well be that the A-theory, or rather a closely related doctrine I call “objectism”, is built into the ultimate constitution of things. (shrink)

Philosophical development of Leibniz's view that time is merely earlier–later order is necessary because neither Leibniz nor modern followers sufficiently answered the Newtonian charge that order does not give quantity. Logically, order is transitive, quantity, as in distance, is not. Quantity, as well as order, is naturally assumed in Newton's absolute time, so that to declare the mere relative order sufficient is to have to show how quantity can arise for it. The modern theory of the continuum, (...) perfectly applicable to Newton's absolute, does not show this but assumes quantity. The development given here shows how interval, instant and simultaneity can be logically developed from Leibniz's insight. (shrink)

This paper argues that idealism can offer a new solution to the problem of relating the “static” presence of things to eternity and the “dynamic” passage of reality in the temporal realm. I first offer a presentation of this problem using the dispute between Aquinas and Scotus, then describe “ontological idealism about time,” as a smaller–scale idealism, and show how it resolves the original problem. I conclude by demonstrating that this view is consonant with the recent emphasis on the (...) ontological dependence of things on God and that it offers a way of bringing together non–eternalist ontologies and the ontological conclusions posited by the special theory of relativity. (shrink)

In this paper, I start with the opposition between the Husserlian project of a phenomenology of the experience of time, started in 1905, and the mathematical and physical theory of time as it comes out of Einstein’s special theory of relativity in the same year. Although the contrast between the two approaches is apparent, my aim is to show that the original program of Husserl’s time theory is the constitution of an objective time and a (...) class='Hi'>time of the world, starting from the intuitive giveness of time, i.e., from time as it appears. To show this, I stress the structural similarity between Husserl’s original question of time and the problem of a phenomenology of space constitution as it was first developed in the his manuscripts from the nineteenth century, in which we find the threefold question of the origin of our representation of space, of the geometrization of intuitive space, and of the constitution of transcendent world space. Finally, I reconsider some of Husserl’s main theses about the phenomenological constitution of objective time in light of the main results of special relativity time-theory, introducing several corrections to central assumptions that underlie Husserl’s theory of time. (shrink)

This book presents an elementary but complete exposition of the relativistic theory of the measurement of intervals in space & time.

A relative tensor calculus is formulated for expressing equations of mathematical physics. A tensor time derivative operator ▽ b a is defined which operates on tensors λia...ib. Equations are written in a rigid, flat, inertial or other coordinate system a, altered to relative tensor notation, and are thereby expressed in general flowing coordinate systems or materials b, c, d, .... Mirror tensor expressions for ▽ b a λic...id and ▽ b a λic...id exist in a relative (...) geometry G if and only if a rigid coordinate system a exists in G, where ▽ b a λic = λ ,0c ic + λkev ckc aic + λ kc ic v b ckc , ▽jcλic = λ ,jc ic + λkcΓ jc kc ie , and v b aic is the velocity of b relative to a with components in c. These operators are convenient in theoretical analyses and can be incorporated into machine programs for the numerical solution of physical problems. (shrink)

In a way similar to classical mechanics where we have the concept of inertial time as expressed in the motions of bodies, in the theory of relativity we can regard the inertial time as the only notion of time at play. The inertial time is expressed also in the propagation of light. This gives rise to a notion of clock—the light clock, which we can regard as a notion derived from the inertial time. The light (...) clock can be seen as a solution of the theory, which complies with the requirement that a clock to be so must have a rate that is independent from its past history. Contrary to Einstein’s view, we do not need the concept of “clock” as an independent concept. This implies, in particular, that we do not need to rely on the notions of atomic clock or atomic time in the theory of relativity. (shrink)

It has been suggested by several philosophers that many of the so-called paradoxes of backward time travel can be resolved if we conceive of the backward time traveller as having a zig-zag or N-shaped world line in spacetime. In this I am in general agreement. But there is still a problem in conceiving of backward time travel this way. In this note I will show how we can solve this problem by conceiving of backward time travel (...) in terms of the closed time-like world lines in certain general relativistic space-times. Indeed, it has often been claimed that such world models as Godei spacetime show that backward time travel is conceivable. Our discussion will help to make clear just why this claim is correct. (shrink)

The need for a time-shift invariant formulation of quantum theory arises from fundamental symmetry principles as well as heuristic cosmological considerations. Such a description then leaves open the question of how to reconcile global invariance with the perception of change, locally. By introducing relative time observables, we are able to make rigorous the Page–Wootters conditional probability formalism to show how local Heisenberg evolution is compatible with global invariance.