In this paper, I discuss one form of the idea that spacetime and gravity might ‘emerge’ from quantum theory, i.e. via a holographic duality, and in particular via AdS/CFT duality. I begin by giving a survey of the general notion of duality, as well as its connection to emergence. I then review the AdS/CFT duality and proceed to discuss emergence in this context. We will see that it is difficult to find compelling arguments for the emergence of full quantum gravity (...) from gauge theory via AdS/CFT, i.e. for the boundary theory's being metaphysically more fundamental than the bulk theory. (shrink)

This article investigates and resolves the question whether gauge symmetry can display analogs of the famous Galileo’s ship scenario. In doing so, it builds on and clarifies the work of Greaves and Wallace on this subject.

As a prolegomenon to understanding the sense in which dualities are theoretical equivalences, we investigate the intuitive `equivalence' of hyper-regular Lagrangian and Hamiltonian classical mechanics. We show that the symplectification of these theories provides a sense in which they are isomorphic, and mutually and canonically definable through an analog of `common definitional extension'.

This article uncovers a foundational relationship between the ‘gauge symmetry’ of a Newton-Cartan theory and the celebrated Trautman Recovery Theorem and explores its implications for recent philosophical work on Newton-Cartan gravitation.

We discuss some aspects of the relation between dualities and gauge symmetries. Both of these ideas are of course multi-faceted, and we confine ourselves to making two points. Both points are about dualities in string theory, and both have the ‘flavour’ that two dual theories are ‘closer in content’ than you might think. For both points, we adopt a simple conception of a duality as an ‘isomorphism’ between theories: more precisely, as appropriate bijections between the two theories’ sets of states (...) and sets of quantities. The first point is that this conception of duality meshes with two dual theories being ‘gauge related’ in the general philosophical sense of being physically equivalent. For a string duality, such as T-duality and gauge/gravity duality, this means taking such features as the radius of a compact dimension, and the dimensionality of spacetime, to be ‘gauge’. The second point is much more specific. We give a result about gauge/gravity duality that shows its relation to gauge symmetries to be subtler than you might expect. For gauge theories, you might expect that the duality bijections relate only gauge-invariant quantities and states, in the sense that gauge symmetries in one theory will be unrelated to any symmetries in the other theory. This may be so in general; and indeed, it is suggested by discussions of Polchinski and Horowitz. But we show that in gauge/gravity duality, each of a certain class of gauge symmetries in the gravity/bulk theory, viz. diffeomorphisms, is related by the duality to a position-dependent symmetry of the gauge/boundary theory. (shrink)

Philosophers of physics and physicists have long been intrigued by the analogies and disanalogies between gravitational theories and gauge theories. Indeed, repeated attempts to collapse these disanalogies have made us acutely aware that there are fairly general obstacles to doing so. Nonetheless, there is a special case space-time dimensions) in which gravity is often claimed to be identical to a gauge theory. I subject this claim to philosophical scrutiny in this article. In particular, I analyse how the standard disanalogies can (...) be overcome in dimensions, and consider whether really licenses the interpretation of gravity as a gauge theory. Our conceptual analysis reveals more subtle disanalogies between gravity and gauge, and connects these to interpretive issues in classical and quantum gravity. 1 Introduction1.1 Motivation1.2 Prospectus2 Disanalogies3 Three-dimensional gravity and gauge3.1 gravity3.2 Chern–Simons3.2.1 Cartan geometry3.2.2 Overcoming obst-gauge via Cartan connections3.3 Disanalogies collapsed4 Two More Disanalogies4.1 What about the symmetries?4.2 The phase spaces of the two theories5 Summary and Conclusion. (shrink)

Rovelli’s “Why Gauge?” offers a parable to show that gauge-dependent quantities have a modal and relational physical significance. We subject the morals of this parable to philosophical scrutiny and argue that, while Rovelli’s main point stands, there are important disanalogies between his parable and Yang-Mills type gauge theory.

We make two points about dualities in string theory. The first point is that the conception of duality, which we will discuss, meshes with two dual theories being ‘gauge related’ in the general philosophical sense of being physically equivalent. The second point is a result about gauge/gravity duality that shows its relation to gauge symmetries to be subtler than one might expect: each of a certain class of gauge symmetries in the gravity theory, that is, diffeomorphisms, is related to a (...) position-dependent symmetry of the gauge theory. (shrink)

The idea that gauge theory has `surplus' structure poses a puzzle: in one much discussed sense, this structure is redundant; but on the other hand, it is also widely held to play an essential role in the theory. In this paper, we employ category-theoretic tools to illuminate an aspect of this puzzle. We precisify what is meant by `surplus' structure by means of functorial comparisons with equivalence classes of gauge fields, and then show that such structure is essential for any (...) theory that represents a rich collection of physically relevant fields which are `local' in nature. (shrink)

Category theory has become central to certain aspects of theoretical physics. Bain has recently argued that this has significance for ontic structural realism. We argue against this claim. In so doing, we uncover two pervasive forms of category-theoretic generalization. We call these ‘generalization by duality’ and ‘generalization by categorifying physical processes’. We describe in detail how these arise, and explain their significance using detailed examples. We show that their significance is two-fold: the articulation of high-level physical concepts, and the generation (...) of new models. 1 Introduction2 Categories and Structuralism 2.1 Categories: abstract and concrete 2.2 Structuralism: simple and ontic3 Bain’s Two Strategies 3.1 A first strategy for defending Objectless 3.2 A second strategy for defending Objectless4 Two Forms of Categorical Generalization 4.1 Generalization by duality 4.2 Generalization by categorification 4.3 The role of category theory in physics5 Conclusion. (shrink)

Rovelli's "Why Gauge?" offers a parable to show that gauge-dependent quantities have a modal and relational physical significance. We subject the morals of this parable to philosophical scrutiny and argue that, while his overarching point stands, there are subtle disanalogies between his parable and our best gauge theories, e.g. Yang-Mills theory and General Relativity.

It is part of information theory folklore that, while quantum theory prohibits the generic cloning of states, such cloning is allowed by classical information theory. Indeed, many take the phenomenon of no-cloning to be one of the features that distinguishes quantum mechanics from classical mechanics. In this paper, we use symplectic geometry to argue that pace conventional wisdom, in the case where one does not include a machine system, there is an analog of the no-cloning theorem for classical systems. However, (...) upon adjoining a non-trivial machine system one finds that, pace the quantum case, the obstruction to cloning disappears for pure states. We then discuss the difference between this result and the quantum case, and show that it can be explained in terms of the rigidity of the theories' respective geometries. Finally, we discuss the relationship between this result and classical no-cloning arguments in the context of symmetric monoidal categories and statistical classical mechanics. (shrink)

Foundations of Relational Realism: A Topological Approach to Quantum Mechanics and the Philosophy of Nature by Michael Epperson and Elias Zafiris sets out to achieve three goals: to develop a version of Whiteheadian metaphysics that the authors call “relational realism”; to formalize relational realism in terms of category theory, in particular sheaf theory; and to use relational realism to solve the interpretative problems of quantum mechanics. These goals are ambitious, to say the least, and all this is leaving aside those (...) sections of FRR which argue that relational realism yields the key to understanding quantum gravity!The text is 388 pages long and comprises two parts. Part I, by Epperson, introduces relational realism and its application to quantum mechanics. Part II, by Zafiris, develops the sheaf theory formalism for relational realism. As the authors say, their exposition is “nonlinear”, and this feature of FRR, alon .. (shrink)

This Element is a concise, high-level introduction to the philosophy of physical symmetry. It begins with the notion of `physical representation' (the kind of empirical representation of nature that we effect in doing physics), and then lays out the historically and conceptually central case of physical symmetry that frequently falls under the rubric of 'the Relativity Principle', or 'Galileo's Ship. This material is then used as a point of departure to explore the key hermeneutic challenge concerning physical symmetry in the (...) last century, namely understanding the physical significance of the notion of 'local' gauge symmetry. The approach taken stresses both the continuity with historically important themes such as the Relativity Principle, as well as novel insights earned by working with contemporary media such as the covariant phase space and derived critical locus formalisms. (shrink)

We construct a notion of teleparallelization for Newton-Cartan theory, and show that the teleparallel equivalent of this theory is Newtonian gravity; furthermore, we show that this result is consistent with teleparallelization in general relativity, and can be obtained by null-reducing the teleparallel equivalent of a five-dimensional gravitational wave solution. This work thus strengthens substantially the connections between four theories: Newton-Cartan theory, Newtonian gravitation theory, general relativity, and teleparallel gravity.

The recent debate about whether gauge symmetries can be empirically significant has focused on the possibility of 'Galileo's ship' types of scenarios, where the symmetries effect relational differences between a subsystem and the environment. However, it has gone largely unremarked that apart from such Galileo's ship scenarios, Greaves and Wallace (2014) proposed that gauge transformations can also be empirically significant in a 'non-relational' manner that is analogous to a Faraday-cage scenario, where the subsystem symmetry is related to a change in (...) a charged boundary state. In this paper, we investigate the question of whether such non-relational scenarios are possible for gauge theories. Remarkably, the answer to this question turns out to be closely related to a foundational puzzle that has driven a host of recent developments at the frontiers of theoretical physics. By drawing on these recent developments, we show that a very natural way of elaborating on Greaves and Wallace's claim of non-relational empirical significance for gauge symmetry is incoherent. However, we also argue that much of what they suggest is correct in spirit: one can indeed construct non-relational models of the kind they sketch, albeit ones where the empirical significance is not witnessed by a gauge symmetry but instead by a superficially similar boundary symmetry. Furthermore, the latter casts doubt on whether one really abandons Galileo's ship in such scenarios. (shrink)

The equivalence principle has constituted one of the cornerstones of discussions in the foundations of spacetime theories over the past century. However, up to this point the principle has been considered overwhelmingly only within the context of relativistic physics. In this article, we demonstrate that the principle has much broader, super-theoretic significance: to do so, we present a unified framework for understanding the principle in its various guises, applicable to both relativistic and Newtonian contexts. We thereby deepen significantly our understanding (...) of the role played by the equivalence principle in a broad class of spacetime theories. (shrink)

The last two decades have seen two significant trends emerging within the philosophy of science: the rapid development and focus on the philosophy of the specialised sciences, and a resurgence of Aristotelian metaphysics, much of which is concerned with the possibility of emergence, as well as the ontological status and indispensability of dispositions and powers in science. Despite these recent trends, few Aristotelian metaphysicians have engaged directly with the philosophy of the specialised sciences. Additionally, the relationship between fundamental Aristotelian concepts—such (...) as "hylomorphism", "substance", and "faculties"—and contemporary science has yet to receive a critical and systematic treatment. _Neo-Aristotelian Perspectives on Contemporary Science _aims to fill this gap in the literature by bringing together essays on the relationship between Aristotelianism and science that cut across interdisciplinary boundaries. The chapters in this volume are divided into two main sections covering the philosophy of physics and the philosophy of the life sciences. Featuring original contributions from distinguished and early-career scholars, this book will be of interest to specialists in analytical metaphysics and the philosophy of science. (shrink)

Recently, there has been some discussion of how Dutch Book arguments might be used to demonstrate the rational incoherence of certain hidden variable models of quantum theory. In this paper, we argue that the 'form of inconsistency' underlying this alleged irrationality is deeply and comprehensively related to the more familiar 'inconsistency' phenomenon of contextuality. Our main result is that the hierarchy of contextuality due to Abramsky and Brandenburger corresponds to a hierarchy of additivity/convexity-violations which yields formal Dutch Books of different (...) strengths. We then use this result to provide a partial assessment of whether these formal Dutch Books can be interpreted normatively. (shrink)

It is now well-known that Newton–Cartan theory is the correct geometrical setting for modelling the quantum Hall effect. In addition, in recent years edge modes for the Newton–Cartan quantum Hall effect have been derived. However, the existence of these edge modes has, as of yet, been derived using only orthodox methodologies involving the breaking of gauge-invariance; it would be preferable to derive the existence of such edge modes in a gauge-invariant manner. In this article, we employ recent work by Donnelly (...) and Freidel in order to accomplish exactly this task. Our results agree with known physics, but afford greater conceptual insight into the existence of these edge modes: in particular, they connect them to subtle aspects of Newton–Cartan geometry and pave the way for further applications of Newton–Cartan theory in condensed matter physics. (shrink)

Publication pressure has been touted to promote questionable research practices (QRP) and scientific or research misconduct (RM). However, logically attractively as it is, there is no unequivocal evidence for this notion, and empirical studies have produced conflicting results. Other than difficulties in obtaining unbiased empirical data, a direct causal relationship between perceived publication pressure (PPP) and QRP/RM is inherently difficult to establish, because the former is a complex biopsychosocial construct that is variedly influenced by multiple personal and environmental factors. To (...) effectively address QRP/RM by tackling the sources of PPP would also be difficult because of the competitive nature of the reward and merit system of contemporary science. We might do better with efforts in enhancing knowledge in research ethics and integrity among the practitioners, as well as institutional infrastructures and mechanisms to fairly and efficiently adjudicate cases of QRP/RM. (shrink)

Hofmann and Holm’s recent survey on issues of research misconduct with PhD graduates culminated with a notable conclusion by the authors: ‘ Scientific misconduct seems to be an environmental issue as much as a matter of personal integrity’. Here, we re-emphasise the usefulness of an education-based countermeasure against toxic research environments or cultures that promote unethical practices amongst the younger researchers. We posit that an adequately conducted course in research ethics and integrity, with a good dose of case studies and (...) analyses, can function in a manner that is metaphorically akin to vaccination. The training would cultivate the ability to analyse and build confidence in young researchers in making decisions with sound moral reasoning as well as in speaking up or arguing against pressure and coercions into unacceptable behaviour. A sufficiently large number of young researchers exposed to research ethics trainings would essentially provide a research community some degree of lasting herd immunity at its broadest base. Beyond passive immunity, a crop of research ethics-savvy young researchers could also play active and influential roles as role models for others at their level and perhaps even help correct the wayward attitudes of some senior researchers and initiate prompt action from institutional policy makers in a bottom-up manner. (shrink)

In mainstream analytic epistemology, Reformed theology has made its presence prominently felt in Reformed epistemology, the view of religious belief according to which religious beliefs can be properly basic and warranted when formed by the proper functioning of the sensus divinitatis, an inborn capacity or faculty for belief in God that can be prompted to generate certain religious beliefs when presented with things (e.g., certain majestic aspects of creation). A major competitor to Reformed epistemology is Wittgensteinian quasi-fideism, a position drawn (...) from the epistemology of Wittgenstein’s On Certainty, according to which some foundational religious commitments are not properly basic beliefs but some kind of apodictic, unshakeable certainties that form part of the structure of one’s rationality and worldview. I argue that the Reformed tradition has contained elements of quasi-fideism at least as far back as Calvin’s account of faith from the Institutes of the Christian Religion, book 3, chapter 2. (shrink)

Unregulated patient treatments and approved clinical trials have been conducted with haematopoietic stem cells and mesenchymal stem cells for children with autism spectrum disorder. While the former direct-to-consumer practice is usually considered rogue and should be legally constrained, regulated clinical trials could also be ethically questionable. Here, we outline principal objections against these trials as they are currently conducted. Notably, these often lack a clear rationale for how transplanted cells may confer a therapeutic benefit in ASD, and thus, have ill-defined (...) therapeutic outcomes. We posit that ambiguous and unsubstantiated descriptions of outcome from such clinical trials may nonetheless appeal to the lay public as being based on authentic scientific findings. These may further fuel caregivers of patients with ASD to pursue unregulated direct-to-consumer treatments, thus exposing them to unnecessary risks. There is, therefore, a moral obligation on the part of those regulating and conducting clinical trials of stem cell-based therapeutic for ASD minors to incorporate clear therapeutic targets, scientific rigour and reporting accuracy in their work. Any further stem cell-based trials for ASD unsupported by significant preclinical advances and particularly sound scientific hypothesis and aims would be ethically indefensible. (shrink)

How can we think about things in the outside world? There is still no widely accepted theory of how mental representations get their meaning. In light of pioneering research, Nicholas Shea develops a naturalistic account of the nature of mental representation with a firm focus on the subpersonal representations that pervade the cognitive sciences.

A clearly written, authoritative introduction to Taylor's work.

This is a book about the meanings of words and how they can combine to form larger meaningful units, as well as how they can fail to combine when the ...

How is consciousness possible? What biological purpose does it serve? And why do we value it so highly? In Soul Dust, the psychologist Nicholas Humphrey, a leading figure in consciousness research, proposes a startling new theory. Consciousness, he argues, is nothing less than a magical-mystery show that we stage for ourselves inside our own heads. This self-made show lights up the world for us and makes us feel special and transcendent. Thus consciousness paves the way for spirituality, and allows (...) us, as human beings, to reap the rewards, and anxieties, of living in what Humphrey calls the "soul niche." Tightly argued, intellectually gripping, and a joy to read, Soul Dust provides answers to the deepest questions. It shows how the problem of consciousness merges with questions that obsess us all--how life should be lived and the fear of death. Resting firmly on neuroscience and evolutionary theory, and drawing a wealth of insights from philosophy and literature..."--Jacket. (shrink)

This volume is about abstract objects and the ways we refer to them in natural language. Asher develops a semantical and metaphysical analysis of these entities in two stages. The first reflects the rich ontology of abstract objects necessitated by the forms of language in which we think and speak. A second level of analysis maps the ontology of natural language metaphysics onto a sparser domain--a more systematic realm of abstract objects that are fully analyzed. This second level reflects the (...) commitments of real metaphysics. The models for these commitments assign truth conditions to natural language discourse. Annotation copyright by Book News, Inc., Portland, OR. (shrink)

In this entertaining and provocative introduction, Royle offers lucid explanations of various key ideas, including deconstruction, undecidability, iterability, differance, aporia, the pharmakon, the supplement, a new enlightenment, and the democracy to come. He also gives attention, however, to a range of less obvious key ideas of Derrida, such as earthquakes, animals and animality, ghosts, monstrosity, the poematic, drugs, gifts, secrets, war, and mourning. Derrida is seen as an extraordinarily inventive thinker, as well as a brilliantly imaginative and often very funny (...) writer. Other critical introductions tend to highlight the specifically philosophical nature and genealogy of his work. Royle's book proceeds in a new and different way, in particular by focusing on the crucial but strange place of literature in Derrida's writings. He thus provides an appreciation and understanding based on detailed reference to Derrida's texts, interwoven with close readings of such writers as Shakespeare, Coleridge, P.B. Shelley, Poe, Emily Brontë, Franz Kafka and Elizabeth Bowen. In doing so, he explores Derrida's consistent view that deconstruction is "a coming-to-terms with literature". He emphasizes the ways in which "literature", for Derrida, is indissociably bound up with other concerns, such as philosophy and psychoanalysis, politics and ethics, responsibility and justice, law and democracy. (shrink)

Identifying arguments -- Formal analysis of arguments -- Presenting your case -- Attacking an argument -- Defending your case -- Cause-and-effect reasoning.

This volume sets out to reverse the neglect.

The authors explore the history of experiments in economics, provide examples of different types of experiments and show that the growing use of experimental methods is transforming economics into an empirical science.

We discuss the rational role of highly inattentive experiences, and argue that they can provide rational support for beliefs.

Proposals to make us smarter than the greatest geniuses or to add thousands of years to our life spans seem fit only for the spam folder or trash can. And yet this is what contemporary advocates of radical enhancement offer in all seriousness. They present a variety of technologies and therapies that will expand our capacities far beyond what is currently possible for human beings. In _Humanity's End,_ Nicholas Agar argues against radical enhancement, describing its destructive consequences. Agar examines (...) the proposals of four prominent radical enhancers: Ray Kurzweil, who argues that technology will enable our escape from human biology; Aubrey de Grey, who calls for anti-aging therapies that will achieve "longevity escape velocity"; Nick Bostrom, who defends the morality and rationality of enhancement; and James Hughes, who envisions a harmonious democracy of the enhanced and the unenhanced. Agar argues that the outcomes of radical enhancement could be darker than the rosy futures described by these thinkers. The most dramatic means of enhancing our cognitive powers could in fact kill us; the radical extension of our life span could eliminate experiences of great value from our lives; and a situation in which some humans are radically enhanced and others are not could lead to tyranny of posthumans over humans. (shrink)

Block’s well-known distinction between phenomenal consciousness and access consciousness has generated a large philosophical literature about putative conceptual connections between the two. The scientific literature about whether they come apart in any actual cases is rather smaller. Empirical evidence gathered to date has not settled the issue. Some put this down to a fundamental methodological obstacle to the empirical study of the relation between phenomenal consciousness and access consciousness. Block (2007) has drawn attention to the methodological puzzle and attempted to (...) answer it. While the evidence Block points to is relevant and important, this paper puts forward a more systematic framework for addressing the puzzle. To give it a label, the approach is to study phenomenal consciousness as a natural kind. The approach allows consciousness studies to move beyond the initial means of identifying instances of the kind, like verbal report, and to find its underlying nature. It is wellrecognised that facts about an underlying kind may allow identification of instances of the kind that do not match the initial means of identification (cp. non-liquid samples of water). This paper shows that the same method can be deployed to investigate phenomenal consciousness independently of access consciousness. (shrink)

In this provocative book, philosopher Nicholas Agar defends the idea that parents should be allowed to enhance their children’s characteristics. Gets away from fears of a Huxleyan ‘Brave New World’ or a return to the fascist eugenics of the past Written from a philosophically and scientifically informed point of view Considers real contemporary cases of parents choosing what kind of child to have Uses ‘moral images’ as a way to get readers with no background in philosophy to think about (...) moral dilemmas Provides an authoritative account of the science involved, making the book suitable for readers with no knowledge of genetics Creates a moral framework for assessing all new technologies. (shrink)

In this provocative book, philosopher Nicholas Agar defends the idea that parents should be allowed to enhance their children’s characteristics. Gets away from fears of a Huxleyan ‘Brave New World’ or a return to the fascist eugenics of the past Written from a philosophically and scientifically informed point of view Considers real contemporary cases of parents choosing what kind of child to have Uses ‘moral images’ as a way to get readers with no background in philosophy to think about (...) moral dilemmas Provides an authoritative account of the science involved, making the book suitable for readers with no knowledge of genetics Creates a moral framework for assessing all new technologies. (shrink)

Proposals to make us smarter than the greatest geniuses or to add thousands of years to our life spans seem fit only for the spam folder or trash can. And yet this is what contemporary advocates of radical enhancement offer in all seriousness. They present a variety of technologies and therapies that will expand our capacities far beyond what is currently possible for human beings. In _Humanity's End,_ Nicholas Agar argues against radical enhancement, describing its destructive consequences. Agar examines (...) the proposals of four prominent radical enhancers: Ray Kurzweil, who argues that technology will enable our escape from human biology; Aubrey de Grey, who calls for anti-aging therapies that will achieve "longevity escape velocity"; Nick Bostrom, who defends the morality and rationality of enhancement; and James Hughes, who envisions a harmonious democracy of the enhanced and the unenhanced. Agar argues that the outcomes of radical enhancement could be darker than the rosy futures described by these thinkers. The most dramatic means of enhancing our cognitive powers could in fact kill us; the radical extension of our life span could eliminate experiences of great value from our lives; and a situation in which some humans are radically enhanced and others are not could lead to tyranny of posthumans over humans. (shrink)