In _Neuroscience and Philosophy_ three prominent philosophers and a leading neuroscientist clash over the conceptual presuppositions of cognitive neuroscience. The book begins with an excerpt from Maxwell Bennett and Peter Hacker's _Philosophical Foundations of Neuroscience_, which questions the conceptual commitments of cognitive neuroscientists. Their position is then criticized by Daniel Dennett and John Searle, two philosophers who have written extensively on the subject, and Bennett and Hacker in turn respond. Their impassioned debate encompasses a wide range of central themes: (...) the nature of consciousness, the bearer and location of psychological attributes, the intelligibility of so-called brain maps and representations, the notion of qualia, the coherence of the notion of an intentional stance, and the relationships between mind, brain, and body. Clearly argued and thoroughly engaging, the authors present fundamentally different conceptions of philosophical method, cognitive-neuroscientific explanation, and human nature, and their exchange will appeal to anyone interested in the relation of mind to brain, of psychology to neuroscience, of causal to rational explanation, and of consciousness to self-consciousness. In his conclusion Daniel Robinson explains why this confrontation is so crucial to the understanding of neuroscientific research. The project of cognitive neuroscience, he asserts, depends on the incorporation of human nature into the framework of science itself. In Robinson's estimation, Dennett and Searle fail to support this undertaking; Bennett and Hacker suggest that the project itself might be based on a conceptual mistake. Exciting and challenging, _Neuroscience and Philosophy_ is an exceptional introduction to the philosophical problems raised by cognitive neuroscience. (shrink)

In a recent work, Popper claims to have solved the problem of induction. In this paper I argue that Popper fails both to solve the problem, and to formulate the problem properly. I argue, however, that there are aspects of Popper's approach which, when strengthened and developed, do provide a solution to at least an important part of the problem of induction, along somewhat Popperian lines. This proposed solution requires, and leads to, a new theory of the role of simplicity (...) in science, which may have helpful implications for science itself, thus actually stimulating scientific progress. (shrink)

Il capitolo riguarda un commento su Maxwell, N. Global philosophy: What philosophy ought to be? Exeter, UK: Imprint-Academic, Societas – Essays in Political & Cultural Criticism..

Many people assume that the claims of scientists are objective truths. But historians, sociologists, and philosophers of science have long argued that scientific claims reflect the particular historical, cultural, and social context in which those claims were made. The nature of scientific knowledge is not absolute because it is influenced by the practice and perspective of human agents. Scientific Perspectivism argues that the acts of observing and theorizing are both perspectival, and this nature makes scientific knowledge contingent, as Thomas Kuhn (...) theorized forty years ago. Using the example of color vision in humans to illustrate how his theory of “perspectivism” works, Ronald N. Giere argues that colors do not actually exist in objects; rather, color is the result of an interaction between aspects of the world and the human visual system. Giere extends this argument into a general interpretation of human perception and, more controversially, to scientific observation, conjecturing that the output of scientific instruments is perspectival. Furthermore, complex scientific principles—such as Maxwell’s equations describing the behavior of both the electric and magnetic fields—make no claims about the world, but models based on those principles can be used to make claims about specific aspects of the world. Offering a solution to the most contentious debate in the philosophy of science over the past thirty years, Scientific Perspectivism will be of interest to anyone involved in the study of science. (shrink)

We present an analysis of Szilard's one-molecule Maxwell's demon, including a detailed entropy accounting, that suggests a general theory of the entropy cost of information. It is shown that the entropy of the demon increases during the expansion step, due to the decoupling of the molecule from the measurement information. It is also shown that there is an entropy symmetry between the measurement and erasure steps, whereby the two steps additivelv share a constant entropy change, but the proportion that (...) occurs during each of the two steps is arbitrary. Therefore the measurement step may be accompanied by an entropy increase, a decrease, or no change at all, and likewise for the erasure step. Generalizing beyond the demon, decorrelation between a physical system and information about that system always causes an entropy increase in the joint system comprised of both the original system and the information. Decorrelation causes a net entropy increase in the universe unless, as in the Szilard demon, the information is used to decrease entropy elsewhere before the correlation is lost. Thus, information is thermodynamically costly precisely to the extent that it is not used to obtain work from the measured system. (shrink)

In a recent paper, we describe how a model of quantum communication based on combining consciousness experiment and entanglement can serve as impetus to stop 5G-caused diseases. Therefore, in this paper we will discuss how entanglement can be explained in terms of quantum theory. This short review may be considered as an effort to bring QM into real problem solving, i.e. telecommunication.

A detailed outline is presented of several convergent points of view connecting the self-dual and anti-self-dual fields with their free data. This is done for the Maxwell and for linearized gravity as exemplifying the approaches. The Sparling equation provides one tool of great power and characterizes one approach. The twistor theory of Penrose yields another equally powerful point of view. The links between these two basic approaches given in this paper provide a unification that allows workers and others with (...) interest in this area to proceed more readily toward the goal of understanding the full nonlinear Einstein equations. (shrink)

The canonical formalism for the Maxwell field on a null surface has been revisited. A new pair of gauge-independent canonical variables is introduced. It is shown that these variables are derivable from a Hamillon-Jacobi functional. The construction of the appropriate C * algebra is carried out in preparation for quantization. The resulting quantum theory is similar to a previous result. It is then shown that one can construct the T-variables of Rovelli and Smolin on the null surface. The Poisson (...) bracket algebra exhibits causal relations along the null rays, but is nonsingular if the loops are restricted to those whose projections along the null rays are not tangent and one-to-one. Finally, there is a brief discussion of the relevance of this work to general relativity. (shrink)

The Lagrangian and Hamiltonian properties of classical electrodynamics models and their associated Dirac quantizations are studied. Using the vacuum field theory approach developed in (Prykarpatsky et al. Theor. Math. Phys. 160(2): 1079–1095, 2009 and The field structure of a vacuum, Maxwell equations and relativity theory aspects. Preprint ICTP) consistent canonical Hamiltonian reformulations of some alternative classical electrodynamics models are devised, and these formulations include the Lorentz condition in a natural way. The Dirac quantization procedure corresponding to the Hamiltonian formulations (...) is developed. The crucial importance of the rest reference systems, with respect to which the dynamics of charged point particles is framed, is explained and emphasized. A concise expression for the Lorentz force is derived by suitably taking into account the duality of electromagnetic field and charged particle interactions. Finally, a physical explanation of the vacuum field medium and its relativistic properties fitting the mathematical framework developed is formulated and discussed. (shrink)

"Contemporary Mind - Some Modern Answers" is a fantastic collection of essays by English science writer John W. Sullivan. They deal with a range of subjects, ranging from mysticism and immortality to the relationship between science and art. John William Navin Sullivan (1886 - 1937) was a literary journalist and popular science writer most famous for his study of Beethoven. He is also responsible for having written some of the earliest non-technical accounts of Einstein's General Theory of Relativity, and he (...) was acquainted with many important writers in London in the 1920s, including John Middleton Murry, Aldous Huxley, Wyndham Lewis, Aleister Crowley and T. S. Eliot. Other notable works by this author include "Aspects of Science" (1923), "Aspects of Science: Second Series" (1926), and An Outline of Modern Knowledge (1931). Contents include: "The Balanced Life," "The Problem of Suffering," "The Necessity of Mysticism," "Human Immortality," "A Dissertation on Beethoven," "The Scientific Outlook," "A Dissertation on Maxwell," "New Principles," "A Dissertation on Newton," "Science and Art," "Mathematics and Culture," "Sir Josiah Stamp," "Mr. Aldous Huxley," etc. Many vintage books such as this are increasingly scarce and expensive. It is with this in mind that we are republishing this volume now in an affordable, modern, high-quality edition complete with the original text and artwork. (shrink)

The gauge compensation fields induced by the differential operators of the Stueckelberg-Schrödinger equation are discussed, as well as the relation between these fields and the standard Maxwell fields; An action is constructed and the second quantization of the fields carried out using a constraint procedure. The properties of the second quantized matter fields are discussed.

A [1983] review, 'Relativity before Einstein' made no mention of the work of Joseph Larmor, whose early derivation of the Lorentz transformation seems to be less well known than those of Lorentz and Poincare. In 1897, Larmor, starting from a first-order transformation similar to Lorentz's first order version, presented the correct form of what is now known as the Lorentz transformation. In his presentation of the theory in 1900 Larmor saw the time dilation effect as a consequence of Maxwell's (...) electromagnetic theory. It was Lorentz who, in 1895, introduced the notion of the relativity of simultaneity (local time), without the time dilation effect. Poincare in 1900 discussed how Lorentz's local time would arise from the procedure of synchronizing moving clocks by exchanging light signals assumed to travel at the same speed in either direction. Lorentz presented the correct version of the transformation in 1899, and discussed the variation of mass with velocity arising from it. In 1902 Lorentz was aware of Larmor's 1897 work but apparently missed its significance. Nevertheless, the credit for the first presentation of the Lorentz transformation including the crucial time dilation belongs to Larmor. (shrink)

The book addresses the question of what are the routes and mechanisms of the theory-change process in science at the level when the change involves the calling in question of a mature theory, i.e. one which has been accepted as accounting very well for a large range of experimental phenomenon.

The book takes the reader from the elementary principles of Newtonian mechanics and Maxwell's equations to hydrodynamics and magnetohydrodynamics equations. The author has intended this book to be conversations, as the title indicates.

The development of physical theory is one of our greatest intellectual achievements. Its products--the currently prevailing theories of physics, astronomy, and cosmology--have proved themselves to possess intrinsic beauty and to have enormous explanatory and predictive power. This anthology of primary readings chronicles the birth and maturation of five such theories (the heliocentric theory, the electromagnetic field theory, special and general relativity, quantum theory, and the big bang theory) in the words of the scientists who brought them to life. It is (...) the first historical account that captures the rich substance of these theories, each of which represents a fascinating story of the interplay of evidence and insight--and of dialogue among great minds. Readers sit in with Copernicus, Kepler, and Galileo as they overturn the geocentric universe; observe the genius of Faraday and Maxwell as they "discover" the electromagnetic field; look over Einstein's shoulder as he works out the details of relativity; listen in as Einstein and Bohr argue for the soul of quantum mechanics in the Completeness Debate; and watch as Hubble and others reveal the history of the universe. The editors' approach highlights the moments of discovery that rise from scientific creativity, and the presentation humanizes the scientific process, revealing the extent to which great scientists were the first to consider the philosophical implications of their work. But, most significantly, the editors offer this as their central thesis: although each was ushered in by a revolution, and each contains counterintuitive elements that delayed its acceptance, these five theories exhibit a continuous rational development that has led them to a permanent place in the worldview of science. Accessible to the general reader yet sufficiently substantive that working scientists will find value in it, The Tests of Time offers an intimate look into how physical theory has been developed, by the brilliant people who have developed it. (shrink)

In accordance with an old suggestion of Asher Peres (1962), we consider the electromagnetic field as fundamental and the metric as a subsidiary field. In following up this thought, we formulate Maxwell’s theory in a diffeomorphism invariant and metric-independent way. The electromagnetic field is then given in terms of the excitation $H = ({\cal H}, {\cal D})$ and the field strength F = (E,B). Additionally, a local and linear “spacetime relation” is assumed between H and F, namely H ~ (...) κ F, with the constitutive tensor κ. The propagation is studied of electromagnetic wave fronts (surfaces of discontinuity) with a method of Hadamard. We find a generalized Fresnel equation that is quartic in the wave covector of the wave front. We discuss under which conditions the waves propagate along the light cone. Thereby we derive the metric of spacetime, up to a conformal factor, by purely electromagnetic methods. (shrink)

Photonic Crystals is the first book to address one of the newest and most exciting developments in physics--the discovery of photonic band-gap materials and their use in controlling the propagation of light. Recent discoveries show that many of the properties of an electron in a semiconductor crystal can apply to a particle of light in a photonic crystal. This has vast implications for physicists, materials scientists, and electrical engineers and suggests such possible developments as an entirely optical computer. Combining cutting-edge (...) research with the basic theoretical concepts behind photonic crystals, the authors present to undergraduates and researchers a concise, readable, and comprehensive text on these novel materials and their applications. The first chapters develop the theoretical tools of photonic crystals in a broad, intuitive fashion, starting from nothing more than Maxwell's equations and Fourier analysis, and include analogies to traditional solid-state physics and quantum theory. There follows an investigation of the unique phenomena that take place within photonic crystals, at defect sites, and at surfaces and interfaces. The authors offer a new treatment of the traditional multilayer film (a one-dimensional photonic crystal), which allows for the extension to higher dimensions and more complex geometries. After exploring the capabilities of photonic crystals to guide and localize light, the authors demonstrate how these notions can be put to work. (shrink)

Essay Review of two books of A.N. Maxwell, last of the Neo-Popperians: The Comprehensibility of the Universe (1998) and The Human World in the Physical Universe (2001).

Over the past years, in books and journals (this journal included), N. Maxwell launched a ferocious attack on B. C. van Fraassen’s view of science called Constructive Empiricism (CE). This attack has been totally ignored. Must we conclude from this silence that no defence is possible and that a fortiori Maxwell has buried CE once and for all? Or is the attack too obviously flawed as not to merit exposure? A careful dissection of Maxwell’s reasoning will make (...) it clear that neither is the case. This dissection includes an analysis of Maxwell’s ‘aberrance–argument’ (omnipresent in his many writings) for the claim that science implicitly and permanently accepts a substantial, metaphysical thesis about the universe, which then paves the way for his own metaphysical-realist hierarchy-view of science. This aberrance-claim, which Maxwell directs against a widely shared and harmful ideology of science called ‘Standard Empiricism’, generally has been ignored too, for more than a quarter of a century. Our conclusions will be that (i) Maxwell’s attacks on CE can be beaten off, and (ii) his ‘aberrance–arguments’ do not establish what Maxwell believes they establish, but (iii) we can draw a number of valuable lessons from these attacks about the nature of science and of the libertarian nature of CE. (shrink)

In the context of a covariant mechanics with Poincaré-invariant evolution parameter τ, Sa'ad, Horwitz, and Arshansky have argued that for the electromagnetic interaction to be well posed, the local gauge function of the field should include dependence on τ, as well as on the spacetime coordinates. This requirement of full gauge covariance leads to a theory of five τ-dependent gauge compensation fields, which differs in significant aspects from conventional electrodynamics, but whose zero modes coincide with the Maxwell theory. The (...) pre-Maxwell fields may exchange mass with charged particles, permitting pair annihilation even at the classical level. The total mass-energy-momentum tensor of the fields and particles is conserved. The Green's functions for the fields provide spacelike and timelike support for correlations, as well as lightlike propagation. A τ-integration of the fields—singling out the massless photons—recovers the standard Maxwell theory, which then has the character of an equilibrium limit of the underlying microscopic dynamics. The pre-Maxwell theory also turns out to be the solution of the inverse problem in variational mechanics: it is shown to be the most general local gauge theory consistent with unconstrained commutation relations in four dimensions. Posed in this framework, the extension to n-dimensions, curved background space, and non-abelian gauge symmetry becomes straightforward. (shrink)

A laboratory-testable, solid-state Maxwell demon is proposed that utilizes the electric field energy of an open-gap p-n junction. Numerical results from a commercial semiconductor device simulator (Silvaco International–Atlas) verify primary results from a 1-D analytic model. Present day fabrication techniques appear adequate for laboratory tests of principle.

Since 2002, at least two kinds of laboratory-testable, solid-state Maxwell demons have been proposed that utilize the electric field energy of an open-gap n-p junction and that seem to challenge the validity of the Second Law of Thermodynamics. In the present paper we present some arguments against the alleged functioning of such devices.

Landauer’s principle is the loosely formulated notion that the erasure of n bits of information must always incur a cost of k ln n in thermodynamic entropy. It can be formulated as a precise result in statistical mechanics, but for a restricted class of erasure processes that use a thermodynamically irreversible phase space expansion, which is the real origin of the law’s entropy cost and whose necessity has not been demonstrated. General arguments that purport to establish the unconditional validity of (...) the law fail. They turn out to depend on the illicit formation of a canonical ensemble from memory devices holding random data. To exorcise Maxwell’s demon one must show that all candidate devices—the ordinary and the extraordinary—must fail to reverse the second law of thermodynamics. The theorizing surrounding Landauer’s principle is too fragile and too tied to a few specific examples to support such general exorcism. Charles Bennett’s recent extension of Landauer’s principle to the merging of computational paths fails for the same reasons as trouble the original principle. (shrink)

Landauer’s principle is the loosely formulated notion that the erasure of n bits of information must always incur a cost of k ln n in thermodynamic entropy. It can be formulated as a precise result in statistical mechanics, but for a restricted class of erasure processes that use a thermodynamically irreversible phase space expansion, which is the real origin of the law’s entropy cost and whose necessity has not been demonstrated. General arguments that purport to establish the unconditional validity of (...) the law fail. They turn out to depend on the illicit formation of a canonical ensemble from memory devices holding random data. To exorcise Maxwell’s demon one must show that all candidate devices—the ordinary and the extraordinary—must fail to reverse the second law of thermodynamics. The theorizing surrounding Landauer’s principle is too fragile and too tied to a few specific examples to support such general exorcism. Charles Bennett’s recent extension of Landauer’s principle to the merging of computational paths fails for the same reasons as trouble the original principle. (shrink)

This paper examines J. C. Maxwell’s electromagnetic field as the key idea for the development of A. N. Whitehead's event ontology. Whitehead viewed Maxwell's electromagnetism as the most revolutionary development of modern physics whereby events rather than substances become the basic units of reality.

We propose a new way of looking at the quantum Maxwell’s demon problem in terms of conditional action. A “conditional action” on a system is a unitary time evolution, selected according to the result of a previous measurement, which can reduce the entropy of the system. However, any conditional action can be realized by an unitary time evolution of a larger system and a subsequent Lüders measurement, whereby the entropy of the entire system is either increased or remains constant. (...) We give some examples that illustrate and confirm our proposal, including the erasure of N qubits and the Szilard engine, thus relating the present approach to the Szilard principle and the Landauer principle that have been discussed as possible solutions of the Maxwell’s demon problem. (shrink)

Originally published in 1973, this book shows that methods developed for the semantics of systems of formal logic can be successfully applied to problems about the semantics of natural languages; and, moreover, that such methods can take account of features of natural language which have often been thought incapable of formal treatment, such as vagueness, context dependence and metaphorical meaning. Parts 1 and 2 set out a class of formal languages and their semantics. Parts 3 and 4 show that these (...) formal languages are rich enought to be used in the precise description of natural languages. Appendices describe some of the concepts discussed in the text. (shrink)

We present a multiscale integrationist interpretation of the boundaries of cognitive systems, using the Markov blanket formalism of the variational free energy principle. This interpretation is intended as a corrective for the philosophical debate over internalist and externalist interpretations of cognitive boundaries; we stake out a compromise position. We first survey key principles of new radical views of cognition. We then describe an internalist interpretation premised on the Markov blanket formalism. Having reviewed these accounts, we develop our positive multiscale account. (...) We argue that the statistical seclusion of internal from external states of the system—entailed by the existence of a Markov boundary—can coexist happily with the multiscale integration of the system through its dynamics. Our approach does not privilege any given boundary, nor does it argue that all boundaries are equally prescient. We argue that the relevant boundaries of cognition depend on the level being characterised and the explanatory interests that guide investigation. We approach the issue of how and where to draw the boundaries of cognitive systems through a multiscale ontology of cognitive systems, which offers a multidisciplinary research heuristic for cognitive science. (shrink)

This paper presents a version of neurophenomenology based on generative modelling techniques developed in computational neuroscience and biology. Our approach can be described as _computational phenomenology_ because it applies methods originally developed in computational modelling to provide a formal model of the descriptions of lived experience in the phenomenological tradition of philosophy (e.g., the work of Edmund Husserl, Maurice Merleau-Ponty, etc.). The first section presents a brief review of the overall project to naturalize phenomenology. The second section presents and evaluates (...) philosophical objections to that project and situates our version of computational phenomenology with respect to these projects. The third section reviews the generative modelling framework. The final section presents our approach in detail. We conclude by discussing how our approach differs from previous attempts to use generative modelling to help understand consciousness. In summary, we describe a version of computational phenomenology which uses generative modelling to construct a computational model of the inferential or interpretive processes that best explain this or that kind of lived experience. (shrink)