This article seeks the origin, in the theories of Ibn al-Haytham (Alhazen), Descartes, and Berkeley, of two-stage theories of spatial perception, which hold that visual perception involves both an immediate representation of the proximal stimulus in a two-dimensional ‘‘sensory core’’ and also a subsequent perception of the three dimensional world. The works of Ibn al-Haytham, Descartes, and Berkeley already frame the major theoretical options that guided visual theory into the twentieth century. The field of visual perception was (...) the first area of what we now call psychology to apply mathematics, through geometrical models as used by Euclid, Ptolemy, Ibn al-Haytham, and Descartes (among others). The article shows that Kepler’s discovery of the retinal image, which revolutionized visual anatomy and entailed fundamental changes in visual physiology, did not alter the basic structure of theories of spatial vision. These changes in visual physiology are advanced especially in Descartes' Dioptrics and his L'Homme. Berkeley develops a radically empirist theory vision, according to which visual perception of depth is learned through associative processes that rely on the sense of touch. But Descartes and Berkeley share the assertion that there is a two-dimensional sensory core that is in principle available to consciousness. They also share the observation that we don't usually perceived this core, but find depth and distance to be phenomenally immediate, a point they struggle to accommodate theoretically. If our interpretation is correct, it was not a change in the theory of the psychology of vision that engendered the idea of a sensory core, but rather the introduction of the theory into a new metaphysical context. (shrink)
In this paper we argue that sensory exploitation, a model from sexual selection theory, deserves more attention in evolutionary thinking about art than it has up until now. We base our argument on the observation that in the past sensory exploitation may have been underestimated in sexual selection theory but that it is now winning field. Likewise, we expect sensory exploitation can play a more substantial role in modeling the evolution of art behavior. Darwin's (...)theory of sexual selection provides a mechanistic basis to explain the evolution of male display traits. This mechanistic approach has proven useful to developing hypotheses about the evolution of human art. Both Boyd and Richerson (1985) and Miller (1998, 1999, 2000, 2001) have applied an indirect-benefit model from sexual selection to the evolution of art behavior. We argue that the mechanistic possibilities sensory exploitation has to offer as a model have remained underexplored so far, so we propose a concept based upon it. From the sensory exploitation perspective it follows that exaptive exploitation of psychosensory biases is a primary force in the evolution of art production (notice that the use of a model from sexual selection does not imply art evolved as a sexual display - we only use it for its mechanism) and that the indirect-benefit model only provides secondary forces. Thus, sensory exploitation may operate alone under some conditions but usually secondary processes as a result of indirect benefits are expected to kick in. The concept of sensory exploitation will need to play a central role in articulating all of the existing hypotheses about art. (shrink)
This article argues that modernist fiction pointedly involves all our senses as part of its reaction to the project of modernity and progress, as well as to Victorian realism; it is not just a response to a heighted sensibility towards new soundscapes, new perceptions of motion and new olfactory experiences in the aftermath of industrialization and modernization. This “rebellion” involves a shift of focus from outer, rational and objective reality to inner, irrational and subjective consciousness, which drives the emphasis on (...) emotional and sensational experience. The article suggests that in light of recent important developments in cognitive, psychological and neurological research, as well as in affect studies and intermedial and multimodal studies, there is reason to revise modernist stylistics. This could predominantly be done within the theoretical field and taxonomy of intermediality, as proposed by Lars Elleström. The latter half of the article discusses some textual modernist samples to more convincingly establish a theory of modernist sensorial aesthetics. (shrink)
Can qualia be analyzed by theories that contain only non-qualitative terms? A host of philosophers including Block, Levine, Nagel, and Jackson have argued that, in principle, they cannot. And yet psychophysicists have advanced explanations that seem to account for sensory appearances in terms of the operations of nervous systems. Here are some examples: Mach bands, the assimilation effect, and the Hermann grid illusion all have to do with the look of things, and all are routinely thought to be a (...) consequence of the structure of visual receptive fields. Simultaneous contrast and auditory tuning—both perceptual effects—are lateral inhibition phenomena. That television sets with only three phosphor colors can replicate natural scenes with thousands of distinguishable colors is due to our eyes having just three photopigments. The difference between a three-type receptoral configuration and an array of thousands of receptors with distinct responses accounts for the fact that hues form a closed loop in color space, whereas there are no closed pitch loops in auditory space. (shrink)
It has been known for over a century that there is an afferent, as well as an efferent, component to the visceral-atonomic nervous system. Despite the fundamental importance of bodily afferent information- sometimes called interoception- to central nervous system control of visceral organ function, emotional-motivational processes, and dysfunction of these processes, including psychosomatic disorders, its role did not receive much attention until quite recently. This is the first comprehensive review of this topic and it covers both neurobiological and psychobiological aspects. (...) The author first defines the issue and gives an historical background starting with the James-Lange theory of emotion, and addresses learning and motivation, roots in Pavlovian conditioning research, and operant conditioning of visceral function. In the second section he reviews recent scientific findings in the neural basis of visceral perception and studies in cardiovascular-respiratory and alimentary interoception. Finally, he discusses several related areas of research and theory including drug state issues, interoception and psychiatric disorders, and bodily consciousness, and suggests directions for future investigation. The book will be of interest to scientists in neurobiology, psychology, and brain imaging, to indivuals in related clinical fields such as psychiatry, neurology, cardiology, gastroenterology, and clinical psychology, and to their students and trainees. (shrink)
Resumo: Percepção sensorial: até hoje um grande mistério filosófico. O presente trabalho divide-se em duas partes. A primeira sintetiza a crítica ao modelo representacionista intracerebral predominante, e enuncia um argumento que prepara o terreno para a segunda parte do trabalho. Nesta, a teoria pragmatista da percepção é equiparada à de Aristóteles, em De Anima. Eis, grosso modo, o argumento: percepção resulta de fatores causais da natureza inerentes à transação organismo ambiente; tais fatores não podem ser encontrados entre os elementos ontológicos (...) revelados na própria percepção; logo a estrutura ontológica revelada na percepção não reflete a total complexidade da transação real organismo ambiente. Esta conclusão é crucial para entender a teoria pragmatista-aristotélica da percepção; passagem da fase sujeito-no-mundo para a fase mundo-no-sujeito, via recepção imaterial de formas - estabelecimento de campo anteceptivo consciente de potencialidades de ação subentendidas em tais formas. Pragmatismo como naturalismo esclarecido: a percepção é a versão histórico-natural mais evoluída do mesmo mecanismo chave-e-fechadura próprio da detecção de formas inerente a interações ontológicas elementares - biológicas e mesmo físico-químicas. Mas em vez de detecção-na-ação nomológica/biológico automática: detecção consciente, em aberto, de possibilidades de ação livre inscritas no ambiente do precipiente.: Even today, sensorial perception is a great philosophic mystery. This work is divided in two parts: The first synthesizes and criticizes the prevailing cerebral representationism model and enunciates an argument that prepares the field to second one. In this second part the pragmatism perceptions theory is compared to Aristotle's De Anima. Here is, in a general way, the argument: perception is the result of nature's cause factors intrinsic to organism environment transaction; these factors cannot be encountered among revealed ontological elements of this same perception; therefore the ontological structure reveled by perception doesn't reflect the totality of the organism-environment's transaction complexity. This conclusion is vital to understand the Aristotelian-pragmatic perception theory: the subject-on-world's transposition to world-on-subject phase, via "immaterial reception of forms"- establishment of the anteceptive field conscious of the action potentialities in such way. Pragmatism naturalism cleared up: the perception is a natural-historic evolved version of this same key-and-locker mechanism proper to form detection intrinsic of elementary ontological, biologic and even physical-chemical interaction. But instead of detection in the automatic nomological/biological action: conscious detection, opened, of free actions possibilities inserted in the percipient environment. (shrink)
In this article I outline how a digital–visual–sensory approach to anthropological ethnography might participate in the making of relationship between design and anthropology. While design anthropology is itself coming of age, the potential of its relationship with applied visual anthropology methodology and theory has not been considered in the existing debates in this field. Here I bring this question to the centre of the discussion through a reflection on the themes, issues and limitations of applied visual anthropology (...) and how, with the ability of design thinking to engage with the future, this might develop. I argue then for a future-oriented applied visual anthropology that engages with the everyday, ethnography and design as processual and situated at the innovative edge of what is possible. (shrink)
Since it was first published, Quantum FieldTheory in a Nutshell has quickly established itself as the most accessible and comprehensive introduction to this profound and deeply fascinating area of theoretical physics. Now in this fully revised and expanded edition, A. Zee covers the latest advances while providing a solid conceptual foundation for students to build on, making this the most up-to-date and modern textbook on quantum fieldtheory available. -/- This expanded edition features several additional (...) chapters, as well as an entirely new section describing recent developments in quantum fieldtheory such as gravitational waves, the helicity spinor formalism, on-shell gluon scattering, recursion relations for amplitudes with complex momenta, and the hidden connection between Yang-Mills theory and Einstein gravity. Zee also provides added exercises, explanations, and examples, as well as detailed appendices, solutions to selected exercises, and suggestions for further reading. (shrink)
I argue that our sensory fields are photon fields. The philosophical foundation here is informed by mind/brain identity theory, such as we find in Russell, Feigl, Lockwood and Chalmers. In brief, given Dyson's observation that all material things consist of quantum fields, and given an identity of mind and brain, our sensory fields are then most plausibly photon fields.
Electromagnetic field oscillations produced by the brain are increasingly being viewed as causal drivers of consciousness. Recent research has highlighted the importance of the body’s various endogenous rhythms in organizing these brain-generated fields through various types of entrainment. We expand this approach by examining evidence of extracerebral shared oscillations between the brain and other parts of the body, in both humans and animals. We then examine the degree to which these data support one of General Resonance Theory’s principles: (...) the Slowest Shared Resonance principle, which states that the combination of micro- to macro-consciousness in coupled field systems is a function of the slowest common denominator frequency or resonance. This principle may be utilized to develop a spatiotemporal hierarchy of brain-body shared resonance systems. It is predicted that a system’s SSR decreases with distance between the brain and various resonating structures in the body. The various resonance relationships examined, including between the brain and gastric neurons, brain and sensory organs, and brain and spinal cord, generally match the predicted SSR relationships, empirically supporting this principle of GRT. (shrink)
This book offers novel interpretations of several of Berkeley's most distinctive philosophical doctrines, including his theory of vision, heterogeneity thesis, anti-abstractionism, immaterialism, likeness principle, and the divine language thesis. Key to those interpretations is a focus on Berkeley's critical use of the Cartesian doctrine of objective presence, which demands causal explanations for the content of sensory ideas.
Action is a means of acquiring perceptual information about the environment. Turning around, for example, alters your spatial relations to surrounding objects and, hence, which of their properties you visually perceive. Moving your hand over an object’s surface enables you to feel its shape, temperature, and texture. Sniffing and walking around a room enables you to track down the source of an unpleasant smell. Active or passive movements of the body can also generate useful sources of perceptual information (Gibson 1966, (...) 1979). The pattern of optic flow in the retinal image produced by forward locomotion, for example, contains information about the direction in which you are heading, while motion parallax is a “cue” used by the visual system to estimate the relative distances of objects in your field of view. In these uncontroversial ways and others, perception is instrumentally dependent on action. According to an explanatory framework that Susan Hurley (1998) dubs the “Input-Output Picture”, the dependence of perception on action is purely instrumental: "Movement can alter sensory inputs and so result in different perceptions… changes in output are merely a means to changes in input, on which perception depends directly" (1998: 342). -/- The action-based theories of perception, reviewed in this entry, challenge the Input-Output Picture. They maintain that perception can also depend in a noninstrumental or constitutive way on action (or, more generally, on capacities for object-directed motor control). This position has taken many different forms in the history of philosophy and psychology. Most action-based theories of perception in the last 300 years, however, have looked to action in order to explain how vision, in particular, acquires either all or some of its spatial representational content. Accordingly, these are the theories on which we shall focus here. -/- We begin in Section 1 by discussing George Berkeley’s Towards a New Theory of Vision (1709), the historical locus classicus of action-based theories of perception, and one of the most influential texts on vision ever written. Berkeley argues that the basic or “proper” deliverance of vision is not an arrangement of voluminous objects in three-dimensional space, but rather a two-dimensional manifold of light and color. We then turn to a discussion of Lotze, Helmholtz, and the local sign doctrine. The “local signs” were felt cues for the mind to know what sort of spatial content to imbue visual experience with. For Lotze, these cues were “inflowing” kinaesthetic feelings that result from actually moving the eyes, while, for Helmholtz, they were “outflowing” motor commands sent to move the eyes. -/- In Section 2, we discuss sensorimotor contingency theories, which became prominent in the 20thcentury. These views maintain that an ability to predict the sensory consequences of self-initiated actions is necessary for perception. Among the motivations for this family of theories is the problem of visual direction constancy—why do objects appear to be stationary even though the locations on the retina to which they reflect light change with every eye movement?—as well as experiments on adaptation to optical rearrangement devices (ORDs) and sensory substitution. -/- Section 3 examines two other important 20th century theories. According to what we shall call the motor component theory, efference copies generated in the oculomotor system and/or proprioceptive feedback from eye-movements are used together with incoming sensory inputs to determine the spatial attributes of perceived objects. Efferent readiness theories, by contrast, look to the particular ways in which perceptual states prepare the observer to move and act in relation to the environment. The modest readiness theory, as we shall call it, claims that the way an object’s spatial attributes are represented in visual experience can be modulated by one or another form of covert action planning. The bold readiness theory argues for the stronger claim that perception just is covert readiness for action. -/- In Section 4, we move to the disposition theory, most influentially articulated by Gareth Evans (1982, 1985), but more recently defended by Rick Grush (2000, 2007). Evans’ theory is, at its core, very similar to the bold efferent readiness theory. There are some notable differences, though. Evans’ account is more finely articulated in some philosophical respects. It also does not posit a reduction of perception to behavioral dispositions, but rather posits that certain complicated relations between perceptual input and behavioral provide spatial content. Grush proposes a very specific theory that is like Evans’ in that it does not posit a reduction, but unlike Evans’ view, does not put behavioral dispositions and sensory input on an undifferentiated footing. (shrink)
This paper examines the impact that recent advances in clinical neurology, introspectionist psychology and neuroscience have upon the philosophical psycho?neural Identity Theory. Topics covered include (i) the nature and properties of phenomenal consciousness based on a study of the ?basic? visual field, i.e. that obtained in the complete dark, the Ganzfeld, and during recovery from occipital lobe injuries; (ii) the nature of the ?body?image? of neurology and its relation to the physical body; (iii) Descartes? error in choosing extension (...) in space as the criterion for distinguishing the physical and the mental; (iv) the technical distinction between sensing and perceiving; (v) why phenomenal Direct Realism is incorrect whereas epistemic DR and the representative theory are correct; (vi) the ontological and topological status of phenomenal space and physical space. This leads to considerations of the current ?binding problems? in neuroscience; the role of the brain mechanisms that construct the sensory fields of phenomenal consciousness; the ?homunculus? fallacy; the key difference between epistemic and non?epistemic perception as revealed by brain injury studies; and how the brain codes information, contrasting topological and vectorial coding, with particular reference to the binding problem. My conclusion is that the Identity Theory is incompatible with the scientific evidence from an integrated approach to modern introspectionist psychology, clinical neurology, and neuroscience. However, Cartesian Dualism is even more incompatible with the evidence. This leaves only two viable theories. The first is Bohr's theory of brain?consciousness complementarity. The second is the Broad?Price?Smythies theory of extension, which is a topological theory of the relation between phenomenal space and physical space. (shrink)
In the 1950s, the term ‘deprivation’ entered American psychiatric discourse. This article examines how the concept of deprivation permeated the field of mental retardation, and became an accepted theory of etiology. It focuses on sensory deprivation and cultural deprivation, and analyzes the interventions developed, based on these theories. It argues that the controversial theory of cultural deprivation derived its scientific legitimization from the theory of sensory deprivation, and was a highly politicized concept that took (...) part in the nature—nurture debate. (shrink)
Quantum fieldtheory (QFT) presents a genuine example of the underdetermination of theory by empirical evidence. There are variants of QFT—for example, the standard textbook formulation and the rigorous axiomatic formulation—that are empirically indistinguishable yet support different interpretations. This case is of particular interest to philosophers of physics because, before the philosophical work of interpreting QFT can proceed, the question of which variant should be subject to interpretation must be settled. New arguments are offered for basing the (...) interpretation of QFT on a rigorous axiomatic variant of the theory. The pivotal considerations are the roles that consistency and idealization play in this case. *Received June 2009; revised August 2009. †To contact the author, please write to: Department of Philosophy, University of Waterloo, 200 University Avenue West, Waterloo, ON N2L 3G1, Canada; e‐mail: [email protected] (shrink)
Quantum fieldtheory (QFT) combines quantum mechanics with Einstein's special theory of relativity and underlies elementary particle physics. This book presents a philosophical analysis of QFT. It is the first treatise in which the philosophies of space-time, quantum phenomena, and particle interactions are encompassed in a unified framework. Describing the physics in nontechnical terms, and schematically illustrating complex ideas, the book also serves as an introduction to fundamental physical theories. The philosophical interpretation both upholds the reality of (...) the quantum world and acknowledges the irreducible cognitive elements in its representation. The interpretation is based on an analysis of our ways of thinking as the are embedded in the logical structure of QFT. The author argues that philosophical categories are significant only if they play active and essential roles in our knowledge and hence constitute part of the theories in actual use. Thus she regards physical theories as primary, extracts their categorical structure, and uses it to rethink key philosophical questions. Among the questions this book tries to answer are: What are the quantum properties independent of measurements? How do we refer to individual things in a continuous field? How do theories relate to objects? What are the general conditions of the world and of our ways of thinking that make possible our knowledge of the microscopic realm, which is so intangible and counterintuitive? As a penetrating analysis of vital themes in contemporary science, the book will engage the interest of students and professionals in physics and philosophy alike. (shrink)
Quantum FieldTheory (QFT) is the mathematical and conceptual framework for contemporary elementary particle physics. In a rather informal sense QFT is the extension of quantum mechanics (QM), dealing with particles, over to fields, i.e. systems with an infinite number of degrees of freedom. (See the entry on quantum mechanics.) In the last few years QFT has become a more widely discussed topic in philosophy of science, with questions ranging from methodology and semantics to ontology. QFT taken seriously (...) in its metaphysical implications seems to give a picture of the world which is at variance with central classical conceptions of particles and fields, and even with some features of QM. -/- The following sketches how QFT describes fundamental physics and what the status of QFT is among other theories of physics. Since there is a strong emphasis on those aspects of the theory that are particularly important for interpretive inquiries, it does not replace an introduction to QFT as such. One main group of target readers are philosophers who want to get a first impression of some issues that may be of interest for their own work, another target group are physicists who are interested in a philosophical view upon QFT. (shrink)
Effective field theories have been a very popular tool in quantum physics for almost two decades. And there are good reasons for this. I will argue that effective field theories share many of the advantages of both fundamental theories and phenomenological models, while avoiding their respective shortcomings. They are, for example, flexible enough to cover a wide range of phenomena, and concrete enough to provide a detailed story of the specific mechanisms at work at a given energy scale. (...) So will all of physics eventually converge on effective field theories? This paper argues that good scientific research can be characterised by a fruitful interaction between fundamental theories, phenomenological models and effective field theories. All of them have their appropriate functions in the research process, and all of them are indispensable. They complement each other and hang together in a coherent way which I shall characterise in some detail. To illustrate all this I will present a case study from nuclear and particle physics. The resulting view about scientific theorising is inherently pluralistic, and has implications for the debates about reductionism and scientific explanation. (shrink)
Neuroscience investigates how neuronal processing circuits work, but it has problems explaining experiences this way. For example, it hasn’t explained how colour and shape circuits bind together in visual processing, nor why colours and other qualia are experienced so differently yet processed by circuits so similarly, nor how to get from processing circuits to pictorial images spread across inner space. Some theorists turn from these circuits to their electromagnetic fields to deal with such difficulties concerning the mind’s qualia, unity, privacy, (...) and causality. They include Kohler, Libet, Popper, Lindahl, Arhem, Charman, Pockett, John, McFadden, Fingelkurts, Maxwell, and Jones. They’re classifiable as computationalist, reductionist, dualist, realist, interactionist, epiphenomenalist, globalist, and localist. However, they’ve never been analysed together as a whole, which hinders evaluations of them. This article tries to rectify this. It concludes that while field theories face challenges, they aren’t easily dismissed, for they draw on considerable evidence and may avoid serious problems in neuroscience concerning the mind’s qualia, unity, causality, and ontology. (shrink)
This article summarizes a variety of current as well as previous research in support of a new theory of consciousness. Evidence has been steadily accumulating that information about a stimulus complex is distributed to many neuronal populations dispersed throughout the brain and is represented by the departure from randomness of the temporal pattern of neural discharges within these large ensembles. Zero phase lag synchronization occurs between discharges of neurons in different brain regions and is enhanced by presentation of stimuli. (...) This evidence further suggests that spatiotemporal patterns of coherence, which have been identified by spatial principal component analysis, may encode a multidimensional representation of a present or past event. How such distributed information is integrated into a holistic percept constitutes the binding problem. How a percept defined by a spatial distribution of nonrandomness can be subjectively experienced constitutes the problem of consciousness. Explanations based on a discrete connectionistic network cannot be reconciled with the relevant facts. Evidence is presented herein of invariant features of brain electrical activity found to change reversibly with loss and return of consciousness in a study of 176 patients anesthetized during surgical procedures. A review of relevant research areas, as well as the anesthesia data, leads to a postulation that consciousness is a property of quantumlike processes, within a brain field resonating within a core of structures, which may be the neural substrate of consciousness. This core includes regions of the prefrontal cortex, the frontal cortex, the pre- and paracentral cortex, thalamus, limbic system, and basal ganglia. (shrink)
The metaphysical commitments of quantum fieldtheory are examined. A thesis of underdetermination as between field and particle approaches to the "elementary particles" is argued for but only if a disputed notion of transcendental individuality is admitted. The superiority of the field approach is further emphasized in the context of heuristics.
Effective FieldTheory (EFT) is the successful paradigm underlying modern theoretical physics, including the "Core Theory" of the Standard Model of particle physics plus Einstein's general relativity. I will argue that EFT grants us a unique insight: each EFT model comes with a built-in specification of its domain of applicability. Hence, once a model is tested within some domain (of energies and interaction strengths), we can be confident that it will continue to be accurate within that domain. (...) Currently, the Core Theory has been tested in regimes that include all of the energy scales relevant to the physics of everyday life (biology, chemistry, technology, etc.). Therefore, we have reason to be confident that the laws of physics underlying the phenomena of everyday life are completely known. (shrink)
Quantum fieldtheory, one of the most rapidly developing areas of contemporary physics, is full of problems of great theoretical and philosophical interest. This collection of essays is the first systematic exploration of the nature and implications of quantum fieldtheory. The contributors discuss quantum fieldtheory from a wide variety of standpoints, exploring in detail its mathematical structure and metaphysical and methodological implications.
According to a Received View, relativistic quantum field theories (RQFTs) do not admit particle interpretations. This view requires that particles be localizable and countable, and that these characteristics be given mathematical expression in the forms of local and unique total number operators. Various results (the Reeh-Schlieder theorem, the Unruh Effect, Haag's theorem) then indicate that formulations of RQFTs do not support such operators. These results, however, do not hold for nonrelativistic QFTs. I argue that this is due to the (...) absolute structure of the classical spacetimes associated with such theories. This suggests that the intuitions that underlie the Received View are non-relativistic. Thus, to the extent that such intuitions are inappropriate in the relativistic context, they should be abandoned when it comes to interpreting RQFTs. (shrink)
This essay considers the extent to which a concept of emergence can be associated with Effective Field Theories (EFTs). I suggest that such a concept can be characterized by microphysicalism and novelty underwritten by the elimination of degrees of freedom from a high-energy theory, and argue that this makes emergence in EFTs distinct from other concepts of emergence in physics that have appeared in the recent philosophical literature.
This document is a set of notes I took on QFT as a graduate student at the University of Pennsylvania, mainly inspired in lectures by Burt Ovrut, but also working through Peskin and Schroeder (1995), as well as David Tong’s lecture notes available online. They take a slow pedagogical approach to introducing classical fieldtheory, Noether’s theorem, the principles of quantum mechanics, scattering theory, and culminating in the derivation of Feynman diagrams.
Algebraic quantum fieldtheory provides a general, mathematically precise description of the structure of quantum field theories, and then draws out consequences of this structure by means of various mathematical tools -- the theory of operator algebras, category theory, etc.. Given the rigor and generality of AQFT, it is a particularly apt tool for studying the foundations of QFT. This paper is a survey of AQFT, with an orientation towards foundational topics. In addition to covering (...) the basics of the theory, we discuss issues related to nonlocality, the particle concept, the field concept, and inequivalent representations. We also provide a detailed account of the analysis of superselection rules by Doplicher, Haag, and Roberts (DHR); and we give an alternative proof of Doplicher and Robert's reconstruction of fields and gauge group from the category of physical representations of the observable algebra. The latter is based on unpublished ideas due to J. E. Roberts and the abstract duality theorem for symmetric tensor *-categories, a self-contained proof of which is given in the appendix. (shrink)
In the April 2002 edition of JCS I outlined the conscious electromagnetic information fieldtheory, claiming that consciousness is that component of the brain's electromagnetic field that is downloaded to motor neurons and is thereby capable of communicating its informational content to the outside world. In this paper I demonstrate that the theory is robust to criticisms. I further explore implications of the theory particularly as regards the relationship between electromagnetic fields, information, the phenomenology of (...) consciousness and the meaning of free will. Using cemi fieldtheory I propose a working hypothesis that shows, among other things, that awareness and information represent the same phenomenon viewed from different reference frames. (shrink)
In this paper I elicit a prediction from structural realism and compare it, not to a historical case, but to a contemporary scientific theory. If structural realism is correct, then we should expect physics to develop theories that fail to provide an ontology of the sort sought by traditional realists. If structure alone is responsible for instrumental success, we should expect surplus ontology to be eliminated. Quantum fieldtheory (QFT) provides the framework for some of the best (...) confirmed theories in science, but debates over its ontology are vexed. Rather than taking a stand on these matters, the structural realist can embrace QFT as an example of just the kind of theory SR should lead us to expect. Yet, it is not clear that QFT meets the structuralist's positive expectation by providing a structure for the world. In particular, the problem of unitarily inequivalent representations threatens to undermine the possibility of QFT providing a unique structure for the world. In response to this problem, I suggest that the structuralist should endorse pluralism about structure. (shrink)
Quantum mechanics is a subject that has captured the imagination of a surprisingly broad range of thinkers, including many philosophers of science. Quantum fieldtheory, however, is a subject that has been discussed mostly by physicists. This is the first book to present quantum fieldtheory in a manner that makes it accessible to philosophers. Because it presents a lucid view of the theory and debates that surround the theory, An Interpretive Introduction to Quantum (...)FieldTheory will interest students of physics as well as students of philosophy. -/- Paul Teller presents the basic ideas of quantum fieldtheory in a way that is understandable to readers who are familiar with non-relativistic quantum mechanics. He provides information about the physics of the theory without calculational detail, and he enlightens readers on how to think about the theory physically. Along the way, he dismantles some popular myths and clarifies the novel ways in which quantum fieldtheory is both a theory about fields and about particles. His goal is to raise questions about the philosophical implications of the theory and to offer some tentative interpretive views of his own. This provocative and thoughtful book challenges philosophers to extend their thinking beyond the realm of quantum mechanics and it challenges physicists to consider the philosophical issues that their explorations have encouraged. (shrink)
The availability of unitarily inequivalent representations of the canonical commutation relations constituting a quantization of a classical fieldtheory raises questions about how to formulate and pursue quantum fieldtheory. In a minimally technical way, I explain how these questions arise and how advocates of the Hilbert space and of the algebraic approaches to quantum theory might answer them. Where these answers differ, I sketch considerations for and against each approach, as well as considerations which (...) might temper their apparent rivalry. (shrink)
This survey covers some of the main philosophical debates raised by the framework of effective field theories during the last decades. It is centered on three issues: whether effective field theories underpin a specific realist picture of the world, whether they support an anti-reductionist picture of physics, and whether they provide reasons to give up the ultimate aspiration of formulating a final and complete physical theory. Reviewing the past and current literature, we argue that effective field (...) theories do not give convincing reasons to adopt a particular stance towards these speculative issues. They hold good prospects for asking ontologically perspicuous and sensible questions about currently accessible domains. With respect to more fundamental questions, however, the only certainty is provisional and instrumental: effective theories are currently indispensable for conducting fruitful scientific research. (shrink)
In recent years, a ''change in attitude'' in particle physics has led to our understanding current quantum field theories as effective field theories (EFTs). The present paper is concerned with the significance of this EFT approach, especially from the viewpoint of the debate on reductionism in science. In particular, I shall show how EFTs provide a new and interesting case study in current philosophical discussion on reduction, emergence, and inter-level relationships in general.
Aron Gurwitsch’s Gestalt-inspired “fieldtheory of consciousness” was introduced in the same period as Wolfgang Köhler’s theory of “electrical brain fields.” I consider parallels between these theories, drawing on results that have emerged in the last five years. First, I consider the claim that fields of consciousness supervene on electromagnetic fields in the brain, then I outline Gurwitsch’s fieldtheory of consciousness, and finally I consider how the structures described by Gurwitsch might relate to structures (...) in the brain’s electro-magnetic field. Along the way, I expose a dogma (that qualia are paradigmatic conscious states) and develop an interpretation of Gurwitsch’s fieldtheory. (shrink)
Quantum fieldtheory provides the framework for many fundamental theories in modern physics, and over the last few years there has been growing interest in its historical and philosophical foundations. This anthology on the foundations of QFT brings together 15 essays by well-known researchers in physics, the philosophy of physics, and analytic philosophy.Many of these essays were first presented as papers at the conference?Ontological Aspects of Quantum FieldTheory?, held at the Zentrum fr interdisziplinre Forschung, Bielefeld, (...) Germany. The essays contain cutting-edge work on ontological aspects of QFT, including: the role of measurement and experimental evidence, corpuscular versus field-theoretic interpretations of QFT, the interpretation of gauge symmetry, and localization.This book is ideally suited to anyone with an interest in the foundations of quantum physics, including physicists, philosophers and historians of physics, as well as general readers interested in philosophy or science. (shrink)
Several theories of consciousness first described about a decade ago, including the conscious electromagnetic information (CEMI) fieldtheory, claimed that the substrate of consciousness is the brain’s electromagnetic (EM) field. These theories were prompted by the observation, in many diverse systems, that synchronous neuronal firing, which generates coherent EM fields, was a strong correlate of attention, awareness, and consciousness. However, when these theories were first described there was no direct evidence that synchronous firing was actually functional, rather (...) than an epiphenomenon of brain function. Additionally, any EM field-based consciousness would be a ‘ghost in the machine’ unless the brain’s endogenous EM field is also able to influence neuron firing. Once again, when these theories were first described, there was only indirect evidence that the brain’s EM field influenced neuron firing patterns in the brain. In this paper I describe recent experimental evidence which demonstrate that synchronous neuronal firing does indeed have a functional role in the brain; and also that the brain’s endogenous EM field is involved in recruiting neurons to synchronously firing networks. The new data point to a new and unappreciated form of neural communication in the brain that is likely to have significance for all theories of consciousness. I describe an extension of the CEMI fieldtheory that incorporates these recent experimental findings and integrates the theory with the ‘communication through coherence’ hypothesis. (shrink)