As recently documented in J. Cushing’s excellent book, throughout its almost fifty-year history, Bohm’s interpretation of quantum mechanics has been systematically misunderstood and ignored. On the rare occasions it was examined, it was usually dismissed for reasons having more to do with politics, religion, positivism, and sloppy thought, than for reasons central to physics. In recent times, however, Bohm’s theory has received much more serious attention from physicists and philosophers, thanks mainly to J. S. Bell’s positive influence on the theory. (...) Most of this work reacts favorably toward Bohm’s theory. And this is not surprising, for Bohm’s theory provides us with a consistent, empirically adequate picture of the quantum world. (shrink)

As we navigate through life, we model time as flowing, the present as special, and the past as “dead.” This model of time—manifest time—develops in childhood and later thoroughly infiltrates our language, thought, and behavior. It is part of what makes a human life recognizably human. Yet if physics is correct, this model of the world is deeply mistaken. This book is about this conflict between manifest and physical time. The first half dives into the physics and philosophy to establish (...) the conflict’s existence; but it also argues that the claim that physics “spatializes” time is overstated. Rather, even relativity theory makes time special in deep and significant ways. The second half turns to psychology, biology, and more, seeking to understand why creatures like us develop manifest time. The novel picture that results is that manifest time is a natural reaction to the many cognitive and evolutionary challenges that we face. For subjects embedded in our circumstances, it makes sense to develop—even if fundamentally wrong. (shrink)

Is the quantum state part of the furniture of the world? Einstein found such a position indigestible, but here I present a different understanding of the wavefunction that is easy to stomach. First, I develop the idea that the wavefunction is nomological in nature, showing how the quantum It or Bit debate gets subsumed by the corresponding It or Bit debate about laws of nature. Second, I motivate the nomological view by casting quantum mechanics in a “classical” formalism (Hamilton–Jacobi theory) (...) and classical mechanics in a “quantum” formalism (Koopman–von Neumann theory) and then comparing and contrasting classical and quantum wave functions. I argue that Humeans about laws can treat classical and quantum wave functions on a par and that doing so yields many benefits. (shrink)

This paper challenges the conventional wisdom dominating the social sciences and philosophy regarding temporal discounting, the practice of discounting the value of future utility when making decisions. Although there are sharp disagreements about temporal discounting, a kind of standard model has arisen, one that begins with a normative standard about how we should make intertemporal comparisons of utility. This standard demands that in so far as one is rational one discounts utilities at future times with an exponential discount function. Tracing (...) the justification for this standard through economics, philosophy and psychology, I’ll make what I believe is the best case one can for it, showing how a non-arbitrariness assumption and a dominance argument together imply that discounting ought to be exponential. Ultimately, however, I don’t find the case compelling. Non-exponential temporal discounting is often rational. If this is correct, Instead of trying to ‘fix’ non-exponential discounting because it is irrational and associated with negative life outcomes, we might instead focus attention on why the conditions obtain that make such discounting rational. (shrink)

The manifest image is teeming with activity. Objects are booming and buzzing by, changing their locations and properties, vivid perceptions are replaced, and we seem to be inexorably slipping into the future. Time—or at least our experience in time— seems a very turbulent sort of thing. By contrast, time in the scientist image seems very still. The fundamental laws of physics don’t differentiate between past and future, nor do they pick out a present moment that flows. Except for a minus (...) sign in the relativistic metric, there are few differences between the temporal and spatial coordinates in natural science. We seem to have, to echo another debate, an “explanatory gap” between time as we find it in experience and as we find it in science. Reconciling these two images of the world is the principal goal of philosophy of time. (shrink)

No one conception of time emerges from a study of physics. As science changes—over time or through varying interpretations at a time—our conception of physical time changes. Each of these changes and resulting theories of time has been the subject of philosophical scrutiny, so there are many philosophical controversies internal to particular physical theories. For instance, the move to special relativity radically transformed our understanding of time, but it also gave rise to debates about the nature of simultaneity within the (...) theory itself. Nevertheless, there are some philosophical puzzles that appear at every stage of the development of physics. Perhaps most generally, there is the perennial question, Is there a ‘gap’ between the conception of time as found in physics and the conception of time as found in philosophy? (shrink)

Quantum mechanics, like any physical theory, comes equipped with many metaphysical assumptions and implications. The line between metaphysics and physics is often blurry, but as a rough guide, one can think of a theory’s metaphysics as those foundational assumptions made in its interpretation that are not usually directly tested in experiment. In classical mechanics some examples of possible metaphysical assumptions are the claims that forces are real, that inertial mass is primitive, and that space is substantival. The distinctive feature of (...) these claims is that they are all rather far removed from ordinary tests of the theory. Newton defended all three of the above claims at one time or other, whereas Mach attacked each one; however, both scientists agreed on enough of the formalism and its connection to experiment to predict (e.g.) the same periods for given pendulums. What they disagreed about were the ingredients necessary to use classical mechanics to explain and understand the world. (shrink)

Philosophy of science appears caught in what Einstein (1933) called the ‘eternal antithesis between the two inseparable components of our knowledge – the empirical and the rational’ (p. 271). It wants to employ metaphysical speculation, but impressed with the methods of the subject it studies, it fears overreaching. Philosophy of science thus tries to walk a fine line between scientifically grounded metaphysics and its more speculative cousins. Here I try to draft some of the contour of this boundary.

No shield can protect scientific realism from dealing with the quantum measurement problem. One may be able to erect barriers around the observable or classical, preserving a realism about tables, chairs and the like, but there is no safety zone within the quantum realm, the domain of our best physical theory. The upshot is not necessarily that scientific realism is in trouble. That conclusion demands further arguments. The lesson instead may be that scientific realists ought to stake their case on (...) particular interpretations of quantum theory. In any case, the realist can’t ignore the interpretational issues plaguing quantum mechanics. (shrink)

Thermodynamics is the science that describes much of the time asymmetric behavior found in the world. This entry's first task, consequently, is to show how thermodynamics treats temporally ‘directed’ behavior. It then concentrates on the following two questions. (1) What is the origin of the thermodynamic asymmetry in time? In a world possibly governed by time symmetric laws, how should we understand the time asymmetric laws of thermodynamics? (2) Does the thermodynamic time asymmetry explain the other temporal asymmetries? Does it (...) account, for instance, for the fact that we know more about the past than the future? The discussion thus divides between thermodynamics being an explanandum or explanans. In the former case the answer will be found in philosophy of physics; in the latter case it will be found in metaphysics, epistemology, and other fields, though in each case there will be blurring between the disciplines. (shrink)

This is the table of contents and first chapter of Physics Meets Philosophy at the Planck Scale (Cambridge University Press, 2001), edited by Craig Callender and Nick Huggett. The chapter discusses the question of why there should be a theory of quantum gravity. We tackle arguments that purport to show that the gravitational field *must* be quantized. We then introduce various programs in quantum gravity and discuss areas where quantum gravity and philosophy seem to have something to say (...) to each other. (shrink)

This article is an introduction to and advertisement of Erwin Schrödinger’s little-known real-valued wave equation, the first published time dependent Schrödinger equation. I argue that this equation is not merely a historical curiosity. Not only does it show that quantum mechanics need not be viewed as essentially complex-valued, but the real formalism also provides a deep insight into the puzzling nature of time reversal in a quantum world. It is hoped that this observation will stimulate the discovery of other areas (...) where ‘keeping it real’ will prove pedagogically or foundationally useful. (shrink)

As the study of time has flourished in the physical and human sciences, the philosophy of time has come into its own as a lively and diverse area of academic research. Philosophers investigate not just the metaphysics of time, and our experience and representation of time, but the role of time in ethics and action, and philosophical issues in the sciences of time, especially with regard to quantum mechanics and relativity theory. This Handbook presents twenty-three specially written essays by leading (...) figures in their fields: it is the first comprehensive collaborative study of the philosophy of time, and will set the agenda for future work. (shrink)

Suppose that God or a demon informs you of the following future fact: despite recent cosmological evidence, the universe is indeed closed and it will have a ‘final’ instant of time; moreover, at that final moment, all 49 of the world’s Imperial Faberge eggs will be in your bedroom bureau’s sock drawer. You’re absolutely certain that this information is true. All of your other dealings with supernatural powers have demonstrated that they are a trustworthy lot.

Are the generalizations of classical equilibrium thermodynamics true of self-gravitating systems? This question has not been addressed from a foundational perspective, but here I tackle it through a study of the “paradoxes” commonly said to afflict such systems. My goals are twofold: (a) to show that the “paradoxes” raise many questions rarely discussed in the philosophical foundations literature, and (b) to counter the idea that these “paradoxes” spell the end for gravitational equilibrium thermodynamics.

This paper considers the possibility that nonrelativistic quantum mechanics tells us that Nature cares about time reversal. In a classical world we have a fundamentally reversible world that appears irreversible at higher levels, e.g., the thermodynamic level. But in a quantum world we see, if I am correct, a fundamentally irreversible world that appears reversible at higher levels, e.g., the level of classical mechanics. I consider two related symmetries, time reversal invariance and what I call ‘Wigner reversal invariance.’ Violation of (...) the first is interesting, for not only would it fly in the face of the usual story about temporal symmetry, but it also appears to imply (as I’ll explain) that time is ‘handed’, or as some have misleadingly said in the literature, ‘anisotropic’. Violation of the second is, as I hope to show, even more interesting. The paper also contains a discussion of two mostly neglected topics: what it means to say time is handed and what warrants such an attribution to time. (shrink)

In a classical mechanical world, the fundamental laws of nature are reversible. The laws of nature treat the past and future as mirror images of each other. Temporally asymmetric phenomena are ultimately said to arise from initial conditions. But are the laws of nature also reversible in a quantum world? This paper argues that they are not, that time in a quantum world prefers a particular 'hand' or ordering. I argue, first, that the probabilistic algorithm used in the theory picks (...) out a preferred direction of time for almost all interpretations of the theory, and second, that contrary to the received wisdom the Schr?dinger evolution is also irreversible. The status of Wigner reversal invariance is then discussed. I conclude that the quantum world is fundamentally irreversible, but manages to appear reversible at the classical level. (shrink)

This chapter unfolds a central philosophical problem of statistical mechanics. This problem lies in a clash between the Static Probabilities offered by statistical mechanics and the Dynamic Probabilities provided by classical or quantum mechanics. The chapter looks at the Boltzmann and Gibbs approaches in statistical mechanics and construes some of the great controversies in the field — for instance the Reversibility Paradox — as instances of this conflict. It furthermore argues that a response to this conflict is a critical choice (...) that shapes one's understanding of statistical mechanics itself, namely, whether it is to be conceived as a special or fundamental science. The chapter details some of the pitfalls of the latter ‘globalist’ position and seeks defensible ground for a kind of ‘localist’ alternative. (shrink)

In the science fiction novel Quarantine, Greg Egan imagines a universe where interactions with human observers collapse quantum wavefunctions. Aliens, unable to collapse wavefunctions, tire of being slaughtered by these collapses. In response they erect an impenetrable shield around the solar system, protecting the rest of the universe from human interference and locking humanity into a starless Bubble. When confronting scientific realism and the quantum, many philosophers try to do the theoretical counterpart of this fictional practical strategy. Quantum mechanics is (...) beset with many hard-to-resolve interpretational challenges. Philosophers — appealing to decoherence and coarse-graining — try to put these in a bubble and hope that they can go about their philosophizing as before. My chapter aims to burst this Bubble. (shrink)

In a classical mechanical world, the fundamental laws of nature are reversible. The laws of nature treat the past and future as mirror images of each other. Temporally asymmetric phenomena are ultimately said to arise from initial conditions. But are the laws of nature also reversible in a quantum world? This paper argues that they are not, that time in a quantum world prefers a particular 'hand' or ordering. I argue, first, that the probabilistic algorithm used in the theory picks (...) out a preferred direction of time for almost all interpretations of the theory, and second, that contrary to the received wisdom the Schr?dinger evolution is also irreversible. The status of Wigner reversal invariance is then discussed. I conclude that the quantum world is fundamentally irreversible, but manages to appear (thanks to Wigner reversal invariance) reversible at the classical level. (shrink)

The no-miracles argument and the pessimistic induction are arguably the main considerations for and against scientific realism. Recently these arguments have been accused of embodying a familiar, seductive fallacy. In each case, we are tricked by a base rate fallacy, one much-discussed in the psychological literature. In this paper we consider this accusation and use it as an explanation for why the two most prominent `wholesale' arguments in the literature seem irresolvable. Framed probabilistically, we can see very clearly why realists (...) and anti-realists have been talking past one another. We then formulate a dilemma for advocates of either argument, answer potential objections to our criticism, discuss what remains (if anything) of these two major arguments, and then speculate about a future philosophy of science freed from these two arguments. In so doing, we connect the point about base rates to the wholesale/retail distinction; we believe it hints at an answer of how to distinguish profitable from unprofitable realism debates. In short, we offer a probabilistic analysis of the feeling of ennui afflicting contemporary philosophy of science. (shrink)

This paper searches for an explicit expression of the so-called problem of the direction of time. I argue that the traditional version of the problem is an artifact of a mistaken view in the foundations of statistical mechanics, and that to the degree it is a problem, it is really one general to all the special sciences. I then search the residue of the traditional problem for any remaining difficulty particular to time's arrow and find that there is a special (...) puzzle for some types of scientific realist. (shrink)

Philosophy of time, as practiced throughout the last hundred years, is both language- and existence-obsessed. It is language-obsessed in the sense that the primary venue for attacking questions about the nature of time—in sharp contrast to the primary venue for questions about space—has been philosophy of language. Although other areas of philosophy have long recognized that there is a yawning gap between language and the world, the message is spreading slowly in philosophy of time.[1] Since twentieth-century analytic philosophy as a (...) whole often drew metaphysical conclusions from arguments with linguistic premises, philosophy of time perhaps may be forgiven for this transgression. Connected to this language-saturated way of doing philosophy, however, is a hitherto unnoticed obsession, equally unhealthy; namely, an obsession with existence. Existence draws the very lines of debate in philosophy of time: “eternalists” believe past, present and future events all ‘equally’ exist, “possibilists” believe that past and present events exist, and “presentists” believe that only present events enjoy this lofty status.[2] These differences between what events exist as of some other time are supposed to explain the main puzzles surrounding time. This fixation on existence, I submit, is a lingering symptom of the language-saturated days of philosophy of time.[3] And just as linguistic issues such as the ineliminability of tense fail to elucidate time and temporal experience, so too do the “existence debates” fail to explain much of what is interesting about time. Philosophers should have more to say about such a fascinating topic. (shrink)

Was the first book to examine the exciting area of overlap between philosophy and quantum mechanics with chapters by leading experts from around the world.

I show how the two great Humean ways of understanding laws of nature, projectivism and systems theory, have unwittingly reprised developments in metaethics over the past century. This demonstration helps us explain and understand trends in both literatures. It also allows work on laws to “leap- frog” over the birth of many new positions, the nomic counterparts of new theories in metaethics. However, like leap-frogging from agriculture to the internet age, it’s hardly clear that we’ve landed in a good place. (...) My reactionary advice is to return to Hume and work on the central insights that motivated Humeanism about modality in the first place. When updated with contemporary insights, there we will find an attractive naturalistic theory of laws, or so I’ll argue, and along the way we’ll see how projectivism and systems theory both get something right about this overall theory. (shrink)

Exponential discounted utility theory provides the normative standard for future discounting as it is employed throughout the social sciences. Tracing the justification for this standard through economics, philosophy and psychology, I’ll make what I believe is the best case one can for it, showing how a non-arbitrariness assumption and a dominance argument together imply that discounting ought to be exponential. Ultimately, however, I don’t find the case compelling, as I believe it is deeply flawed. Non-exponential temporal discounting is often rational–indeed, (...) the paragon of rationality. If this is correct, it’s an important point when considering policy interventions. Instead of trying to “fix” non-exponetial discounting because it is irrational and associated with negative life outcomes, we might instead focus attention on why the conditions obtain that make such discounting rational. (shrink)

Collection of original essays by leading philosophers on a range of questions about time.

We propose that scientific representation is a special case of a more general notion of representation, and that the relatively well worked-out and plausible theories of the latter are directly applicable to thc scientific special case. Construing scientific representation in this way makes the so-called “problem of scientific representation” look much less interesting than it has seerned to many, and suggests that some of the (hotly contested) debates in the literature are concerned with non-issues.

Throughout its history, Bohm's interpretation of quantum mechanics has been systematically misunderstood and ignored. It was often dismissed for reasons having more to do with politics, religion, positivism, and sloppy thought, than for reasons central to physics. Still, like any physical theory, Bohm's theory faces challenges of varying degrees of severity. Here we review and evaluate some of these challenges.

Many believe that quantum mechanics makes the world hospitable to the tensed theory of time. Quantum mechanics is said to rescue the significance of the present moment, the mutability of the future and possibly even the whoosh of time’s flow. It allegedly does so in two different ways: by making a preferred foliation of spacetime into space and time scientifically respectable, and by wavefunction collapse injecting temporal ‘becoming’ into the world. The aim of this paper is to show that the (...) reasoning underlying these claims is wishful thinking. Against the first claim I develop what I call the “coordination problem” for tensers. The upshot of this problem is that if tensers escape the threat of relativity, they do so only by embracing conflict with the branch of physics they believed saved them, quantum mechanics. I then step back from the fray and examine some methodological issues, concluding that scientific methodology will always be “against” tenses as they are currently conceived. The Appendix deals with the confused tangle of issues linking wavefunction collapse to an open future. (shrink)

This paper discusses the mistake of understanding the laws and concepts of thermodynamics too literally in the foundations of statistical mechanics. Arguing that this error is still made in subtle ways, the article explores its occurrence in three examples: the Second Law, the concept of equilibrium and the definition of phase transitions.

How should one discount utility across time? The conventional wisdom in social science is that one should use an exponential discount function. Such a function is a representation of the axioms that provide a well-defined utility function plus a condition known as stationarity. Yet stationarity doesnt really have much intuitive normative pull on its own. Here I try to cast it in a normative glow by deriving stationarity from two explicitly normative premises, both suggested by the philosophical thesis of temporal (...) neutralism. Putting the argument in this form helps us better understand exponential discounting and challenges to it. (shrink)

This article argues that most of the approaches to the foundations of statistical mechanics have severed their link with the original foundational project, the project of demonstrating how real mechanical systems can behave thermodynamically.

Throughout this century many philosophers and physicists have gone for thc ‘big ki11’ regarding tenses. They have tried to show via McTaggart’s paradox and special relativity that tcnscs arc logically and physically impossible, rcspcctivcly. Ncithcr attempt succccds, though as I argue, both lcavc their mark. In thc iirst two sections of thc paper I introduce some conceptual difficulties for the tensed theory of time. The next section then discusses the standing 0f tenses in light of special relativity, cspccially rcccnt work (...) by Stcin on thc topic. I argue that, Stcin’s possibility thcorcm notwithstanding, special relativity is inconsistent with any philosophicully interesting conception of tense. Finally, I search for help for tenses in the broader context of quantum theory, Lorcntzian interpretations 0f time dilation/length contraction, and gcncral relativistic spacctimcs. I suggest that these avenues d0 not provide tenses the home for which some have hoped. (shrink)

An important feature of life is the temporal value asymmetry. Not to be confused with temporal discounting, the value asymmetry is the fact that we prefer future rather than past preferences be satisfied. Misfortunes are better in the past--where they are "over and done"--than in the future. Using recent work in empirical psychology and evolutionary theory, we develop a theory of the nature and causes of the temporal value asymmetry. The account we develop undercuts philosophy of time arguments such as (...) that of Prior (1959), but more importantly, also begins a serious study of an interesting but understudied feature of our valuations and emotional attitudes. While in the spirit of certain past sketches about the possible origins of the temporal value asymmetry, our theory improves on them in many significant respects and suggests many clear avenues of future study. More generally, our hope is that work on the temporal value asymmetry will eventually attain the degree of rigor and explanatory power that the discounting asymmetry presently enjoys, for like this latter asymmetry, we believe the temporal value asymmetry has relevance to many practical issues in decision-making. Our paper can thus be seen as a call for a more unified methodological treatment of the two temporal asymmetries. (shrink)

We propose that scientific representation is a special case of a more general notion of representation, and that the relatively well worked-out and plausible theories of the latter are directly applicable to the scientific special case.

For the generalizations of thermodynamics to obtain, it appears that a very ‘special’ initial condition of the universe is required. Is this initial condition itself in need of explanation? I argue that it is not. In so doing, I offer a framework in which to think about ‘special’ initial conditions in all areas of science, though I concentrate on the case of thermodynamics. I urge the view that it is not always a serious mark against a theory that it must (...) posit an ‘improbable’ initial condition. (shrink)

Why does time seem to flow in one direction? Can we influence the past? Is only the present real? Does relativity conflict with our common understanding of time? How does time relate to free will? Could science do away with time? These questions and others about time are among the most puzzling problems in philosophy and science. In this exciting collection of original articles, eminent philosophers propose novel answers to these and other questions. Based on the latest research in philosophy (...) and physics, these essays will be enjoyable to anyone with a speculative turn of mind. (shrink)

This is my commentary on Jonathan Schaffer's paper "Evidence for Fundamentality?”; both the paper and comments were presented at the Pacific APA, San Francisco, March 2001. Schaffer argues against the view that there is an ultimate fundamental level to the world. Seeing that quarks and leptons may have an infinite hierarchy of constituents, he claims, “empowers and dignifies the whole of nature” (15). Like Kant he holds that there are as good reasons for believing matter infinitely divisible as composed of (...) fundamental simples. I’m afraid that Schaffer’s provocative arguments have not convinced me. In the paper, I criticize the idea that fundamentalism 'weakens' and 'denigrates' the whole of nature and try to show that an infinite hierarchy can not do the work Schaffer needs it to. I then argue that we should not in fact be agnostic between the two rival hypotheses. (shrink)

By developing an absurd counterfactual history, I show that many objections launched against Bohmian mechanics could also have been made against Newtonian mechanics. This paper introduces readers to Koopman–von Neumann dynamics, an operator-based Hilbert space representation of classical statistical mechanics. Lessons for quantum foundations are drawn by replaying the battles between advocates of standard quantum theory and Bohmian mechanics in a fictional classical history.

A realist causal model of quantum cosmology (QC) is developed. By applying the de Broglie-Bohm interpretation of quantum mechanics to QC, we resolve the notorious 'problem of time' in QC, and derive exact equations of motion for cosmological dynamical variables. Due to this success, it is argued that if the situation in QC is used as a yardstick by which other interpretations are measured, the de Broglie-Bohm theory seems uniquely fit as an interpretation of quantum mechanics.

For much of this century, philosophers hoped that Einstein’s general theory of relativity would play the role of physician to philosophy. Its development would positively influence the philosophy of methodology and confirmation, and its ontology would answer many traditional philosophical debates—for example, the issue of spacetime substantivalism. In physics, by contrast, the attitude is increasingly that GTR itself needs a physician. The more we learn about GTR the more we discover how odd are the spacetimes that it allows. Not only (...) does GTR permit singularities, naked and clothed, but it allows time travel, topology change, and event and particle horizons, to name but a few of these oddities. Rather than revel in the riches of the theory, however, many physicists seek to rule out one or more of the above “pathologies” on the grounds that they are “physically unreasonable.” Thus contemporary researchers hawk various “cures” for the “illnesses” of GTR: among them, Chronology Protection to ensure against time travel, Cosmic Censorship for naked singularities, Inflation for horizons, and so on. The physics of these illnesses and cures, and the problems they engender, are the source of much controversy in the physics literature. Philosophers have largely neglected it. But clearly the subject needs philosophers of physics to determine whether the patient is genuinely ailing, and if so, to sift the real antidotes from the snake oil. (shrink)

A persistent question about the deBroglie–Bohm interpretation of quantum mechanics concerns the understanding of Born’s rule in the theory. Where do the quantum mechanical probabilities come from? How are they to be interpreted? These are the problems of emergence and interpretation. In more than 50 years no consensus regarding the answers has been achieved. Indeed, mirroring the foundational disputes in statistical mechanics, the answers to each question are surprisingly diverse. This paper is an opinionated survey of this literature. While acknowledging (...) the pros and cons of various positions, it defends particular answers to how the probabilities emerge from Bohmian mechanics and how they ought to be interpreted. (shrink)

The Past Hypothesis is the claim that the Boltzmann entropy of the universe was extremely low when the universe began. Can we make sense of this claim when *classical* gravitation is included in the system? I first show that the standard rationale for not worrying about gravity is too quick. If the paper does nothing else, my hope is that it gets the problems induced by gravity the attention they deserve in the foundations of physics. I then try to make (...) plausible a very weak claim: that there is a well-defined Boltzmann entropy that *can* increase in *some* interesting self-gravitating systems. More work is needed before we can say whether this claim answers the threat to the standard explanation of entropy increase. (shrink)

A persistent question about the deBroglie–Bohm interpretation of quantum mechanics concerns the understanding of Born’s rule in the theory. Where do the quantum mechanical probabilities come from? How are they to be interpreted? These are the problems of emergence and interpretation. In more than 50 years no consensus regarding the answers has been achieved. Indeed, mirroring the foundational disputes in statistical mechanics, the answers to each question are surprisingly diverse. This paper is an opinionated survey of this literature. While acknowledging (...) the pros and cons of various positions, it defends particular answers to how the probabilities emerge from Bohmian mechanics and how they ought to be interpreted. (shrink)

Black hole thermodynamics is regarded as one of the deepest clues we have to a quantum theory of gravity. It motivates scores of proposals in the field, from the thought that the world is a hologram to calculations in string theory. The rationale for BHT playing this important role, and for much of BHT itself, originates in the analogy between black hole behavior and ordinary thermodynamic systems. Claiming the relationship is “more than a formal analogy,” black holes are said to (...) be governed by deep thermodynamic principles: what causes your tea to come to room temperature is said additionally to cause the area of black holes to increase. Playing the role of philosophical gadfly, we pour a little cold water on the claim that BHT is more than a formal analogy. First, we show that BHT is often based on a kind of caricature of thermodynamics. Second, we point out an important ambiguity in what systems the analogy is supposed to govern, local or global ones. Finally, and perhaps worst, we point out that one of the primary motivations for the theory arises from a terribly controversial understanding of entropy. BHT may be a useful guide to future physics. Only time will tell. But the analogy is not nearly as good as is commonly supposed. (shrink)