Bohm 's approach to quantum field theory is illustrated through its application to cavity quantum scalar field dynamics. Specific calculations demonstrate how the evolution of the well-defined scalar field is governed by the nature of its quantum state. The implications of the nonlocality inherent in quantum mechanics and the meaning of the classical limit are discussed in this context.

We revisit the concept of de Sitter (dS) ‘tachyonic’ scalar fields, characterized by discrete negative squared mass values, and assess their physical significance through a rigorous Wigner-inspired group-theoretical analysis. This perspective demonstrates that such fields, often misinterpreted as inherently unstable due to their mass parameter, are best understood within the framework of unitary irreducible representations (UIRs) of the dS group. The discrete mass spectrum arises naturally in this representation framework, offering profound insights into the interplay between dS (...) relativity and quantum field theory. Contrary to their misleading nomenclature, we argue that the ‘mass’ parameter associated with these fields lacks intrinsic physical relevance, challenging traditional assumptions that link it to physical instability. Instead, any perceived instability originates from mismanagement of the system’s inherent gauge invariance rather than the fields themselves. A proper treatment of this gauge symmetry, particularly through the Gupta–Bleuler formalism, restores the expected characteristics of these fields as free quantum entities in a highly symmetric spacetime. This study seeks to dispel misconceptions surrounding dS ‘tachyonic’ fields, underscoring the importance of precise terminology and robust theoretical tools in addressing their unique properties. (shrink)

In the recent literature, it has been shown that the wave function in the de Broglie–Bohm theory can be regarded as a new kind of field, i.e., a "multi-field", in three-dimensional space. In this paper, I argue that the natural framework for the multi-field is the original second-order Bohm’s theory. In this context, it is possible: i) to construe the multi-field as a real-valued scalar field; ii) to explain the physical interaction between the multi-field and the Bohmian particles; and (...) iii) to clarify the status of the energy-momentum conservation and the dynamics of the theory. (shrink)

The deterministic process of the detection of a single quantum of energy in Bohm's approach to quantum field theory is illustrated using the Jaynes-Cummings model with a scalar field. The nonlocality of differing quantum states of the scalar field is also explored, and this description is compared with the causal picture of an unquantized field acting on the detector.

We construct a world model consisting of a matter field living in 4 dimensional spacetime and a gravitational field living in 11 dimensional spacetime. The seven hidden dimensions are compactified within a radius estimated by reproducing the particle–wave characteristics of diffraction experiments. In the presence of matter fields the gravitational field develops localized modes with elementary excitations called gravonons which are induced by the sources. The final world model treated here contains only gravonons and a scalar matter field. (...) The gravonons are localized in the environment of the massive particles which generate them. The solution of the Schrödinger equation for the world model yields matter fields which are localized in the 4 dimensional subspace. The localization has the following properties: There is a chooser mechanism for the selection of the localization site. The chooser selects one site on the basis of minor energy differences and differences in the gravonon structure between the sites, which at present cannot be controlled experimentally and therefore let the choice appear statistical. The changes from one localization site to a neighbouring one take place in a telegraph-signal like manner. The times at which telegraph like jumps occur depend on subtleties of the gravonon structure which at present cannot be controlled experimentally and therefore let the telegraph-like jumps appear statistical. The fact that the dynamical law acts in the configuration space of fields living in 11 dimensional spacetime lets the events observed in 4 dimensional spacetime appear non-local. In this way the phenomenology of CQM is obtained without the need of introducing the process of collapse and a probabilistic interpretation of the wave function. Operators defining observables need not be introduced. All experimental findings are explained in a deterministic way as a consequence of the time development of the wave function in configuration space according to Schrödinger’s equation without the need of introducing a probabilistic interpretation. (shrink)

We discuss the intimate connection between the chaotic dynamics of a classical field theory and the instability of the one-loop effective action of the associated quantum field theory. Using the example of massless scalar electrodynamics, we show how the radiatively induced spontaneous symmetry breaking stabilizes the vacuum state against chaos, and we speculate that monopole condensation can have the same effect in non-Abelian gauge theories.

We deal with Lagrangians which are not the standard scalar ones. We present a short review of tensor Lagrangians, which generate massless free fields and the Dirac field, as well as vector and pseudovector Lagrangians for the electric and magnetic fields of Maxwell’s equations with sources. We introduce and analyse Lagrangians which are equivalent to the Hamilton-Jacobi equation and recast them to relativistic equations.

We argue that, under certain plausible assumptions, de Sitter space settles into a quiescent vacuum in which there are no dynamical quantum fluctuations. Such fluctuations require either an evolving microstate, or time-dependent histories of out-of-equilibrium recording devices, which we argue are absent in stationary states. For a massive scalar field in a fixed de Sitter background, the cosmic no-hair theorem implies that the state of the patch approaches the vacuum, where there are no fluctuations. We argue that an analogous (...) conclusion holds whenever a patch of de Sitter is embedded in a larger theory with an infinite-dimensional Hilbert space, including semiclassical quantum gravity with false vacua or complementarity in theories with at least one Minkowski vacuum. This reasoning provides an escape from the Boltzmann brain problem in such theories. It also implies that vacuum states do not uptunnel to higher-energy vacua and that perturbations do not decohere while slow-roll inflation occurs, suggesting that eternal inflation is much less common than often supposed. On the other hand, if a de Sitter patch is a closed system with a finite-dimensional Hilbert space, there will be Poincaré recurrences and dynamical Boltzmann fluctuations into lower-entropy states. Our analysis does not alter the conventional understanding of the origin of density fluctuations from primordial inflation, since reheating naturally generates a high-entropy environment and leads to decoherence, nor does it affect the existence of non-dynamical vacuum fluctuations such as those that give rise to the Casimir effect. (shrink)

We analyze the flow into inflation for generic "single-clock" systems, by combining an effective field theory approach with a dynamical-systems analysis. In this approach, we construct an expansion for the potential-like term in the effective action as a function of time, rather than specifying a particular functional dependence on a scalar field. We may then identify fixed points in the effective phase space for such systems, order-by-order, as various constraints are placed on the Mth time derivative of the potential-like (...) function. For relatively simple systems, we find significant probability for the background spacetime to flow into an inflationary state, and for inflation to persist for at least 60 efolds. Moreover, for systems that are compatible with single-scalar-field realizations, we find a single, universal functional form for the effective potential, $V$, which is similar to the well-studied potential for power-law inflation. We discuss the compatibility of such dynamical systems with observational constraints. (shrink)

When the history of life on earth is viewed as a history of cell division, all of life becomes a single cell lineage. The growth and differentiation of this lineage in reciprocal interaction with its environment can be viewed as a developmental process; hence the evolution of life on earth can also be seen as the development of life on earth. Here, in reviewing this field, some potentially fruitful research directions suggested by this change in perspective are highlighted. Variation and (...) selection become, for example, bidirectional information flows between scales, while the notions of “cooperation” and “competition” become scale relative. The language of communication, inference, and information processing becomes more useful than the language of causation to describe the interactions of both homogeneous and heterogeneous living systems at any scale. Emerging scale‐free theoretical frameworks such as predictive coding and active inference provide conceptual tools for reconceptualizing biology as the study of a unified, multiscale dynamical system. (shrink)

In this paper, we use the differential forms of three-dimensional Euclidean space to realize a Clifford algebra which is isomorphic to the algebra of the Pauli matrices or the complex quaternions. This is an associative vector-antisymmetric tensor algebra with division: We provide the algebraic inverse of an eight-component spinor field which is the sum of a scalar + vector + pseudovector + pseudoscalar. A surface of singularities is defined naturally by the inverse of an eight-component spinor and corresponds to (...) a generalized Minkowski “double” light cone in the parameter space. A general description of finite spatial rotations, which utilizes the Baker-Campbell-Hausdorff formula, generalizes the usual infinitesimal treatments of the rotation group. We derive an explicit expression for the angle corresponding to two successive finite rotations in any direction. We also discuss Lorentz transformations and duality rotations of the electromagnetic field and exhibit a relationship between the algebraic inverse and a duality rotated field. Using a combined transformation, one can always transform an arbitrary electromagnetic field (E≠0) into a pure electric field, but never into a pure magnetic field. (shrink)

The purpose of this paper is to introduce the notions of mediational fields and dynamic situated senses as a way to identify the structure of experiences, thoughts and their relations. To reach this purpose I draw some lessons from the debate between Dreyfus and McDowell about the structure of experience, from Cussins’s conception of mediational contents, and from Evans’s account of singular senses. I notice firstly that McDowell’s answer to Dreyfus consists in developing a practical and demonstrative notion of (...) the products of our conceptual capacities. A conception that entails that human experience is not entirely characterised in terms of an abstract specification of truth-conditions. McDowell and Cussins endorse Evans’s conception of singular senses. A specification that takes into account the dynamic and situated abilities involved in making reference. Whereas the first argues in favour of a conceptual conception of experience, the second one argues in favour of a nonconceptual conception. I introduce the notions of mediational fields and dynamic situated senses to argue that both converge in conceiving the contents of experience as mediational and not reducible to an abstract specification of truth-conditions. My proposal is to define a bidimensional space orthogonal to the conceptual/ nonconceptual, experience/thought, know-how/know-that dichotomies. Cognitive contents are ways to disclose the world both as mediational fields and as referential structures. The degree in which those elements are presented determine different varieties of cognition. I use the previous notions to develop the sketch of an account of singular, objective and contextual ways of cognition, and to argue that it is better to begin an enquiry about cognition with notions that do not presuppose a distinction between practical and intellectual capacities. (shrink)

Philosophers of physics should be more attentive to the role energy conditions play in General Relativity. I review the changing status of energy conditions for quantum fields-presently there are no singularity theorems for semiclassical General Relativity. So we must reevaluate how we understand the relationship between General Relativity, Quantum Field Theory, and singularities. Moreover, on our present understanding of what it is to be a physically reasonable field, the standard energy conditions are violated classically. Thus the singularity theorems are (...) unavailable for classical General Relativity. Our understanding of singularities in General Relativity turns on delicate issues of what it is to be a matter field-issues distinct from the content of the theory. (shrink)

The first volume of the Brandeis University Summer Institute lecture series of 1970 on theories of interacting elementary particles, consisting of four sets of lectures. Every summer since 1959 Brandeis University has conducted a lecture series centered on various areas of theoretical physics. The areas are sufficiently broad to interest a large number of physicists and the lecturers are among the original explorers of these areas. The 1970 lectures, presented in two volumes, are on theories of interacting elementary particles. The (...) four lecturers of Volume 1, and the range of the topics they cover, are as follows: Stephen L. Adler on "Perturbation Theory Anomalies": introduction and review of perturbation theory; the VVA triangle anomaly; absence of radiative corrections; generalizations of our results; connection between Ward identity anomalies and commutator anomalies; applications of the Bjorken limit; and breakdown of the Bjorken limit in perturbation theory. Stanley Mandelstam on "Dynamical Applications of the Veneziano formula for the four-point scalar amplitude; factorization; the operator formalism; Veneziano-type quark models; and higher-order Feynman-like diagrams. Steven Weinberg on "Dynamic and Algebraic Symmetries": Introduction; hadron electrodynamics; local symmetries; and chirality. Wolfhart Zimmermann on "Local Operator Products and Renormalization in Quantum Field Theory": introduction; renormalization; operator product expansions; and local field equations. The second volume contains lectures by Rudolf Haag on observables and fields, by Maurice Jacob on duality, by Michael Reed on non-Fock representations, and by Bruno Zumino on effective Lagrangians and broken symmetries. (shrink)

We present a stochastic theory for the nonequilibriurn dynamics of charges moving in a quantum scalar field based on the worldline influence functional and the close-time-path (CTP or in-in) coarse-grained effective action method. We summarize (1) the steps leading to a derivation of a modified Abraham-Lorentz-Dirac equation whose solutions describe a causal semiclassical theory free of runaway solutions and without pre-acceleration patholigies, and (2) the transformation to a stochastic effective action, which generates Abraham-Lorentz-Dirac-Langevin equations depicting the fluctuations of (...) a particle’s worldline around its semiclassical trajectory. We point out the misconceptions in trying to directly relate radiation reaction to vacuum fluctuations, and discuss how, in the framework that we have developed, an array of phenomena, from classical radiation and radiation reaction to the Unruh effect, are interrelated to each other as manifestations at the classical, stochastic and quantum levels. Using this method we give a derivation of the Unruh effect for the spacetime worldline coordinates of an accelerating charge. Our stochastic particle-field model, which was inspired by earlier work in cosmological backreaction, can be used as an analog to the black hole backreaction problem describing the stochastic dynamics of a black hole event horizon. (shrink)

Inspired by “One Note Samba,” a standard jazz repertoire, we present an outline of Bose-Einstein Condensate Cosmology (BECC). Although this approach seems awkward and a bit off the wall at first glance, it is not impossible to connect altogether BEC, Scalar Field Cosmology and Feshbach Resonance with Ermakov-Pinney equation. We also discuss shortly possible link with our previous paper, where we describe Newtonian Universe with Vortex in terms of Ermakov equation.

In this volume we situate the future directions of feminist phenomenology in the here and now. We contend that in this moment feminist phenomenology is well positioned to take a leading role, not simply in terms of consolidating existing feminist methodologies but also in engaging the difficult task of thinking through the actual in the fullness of its relational, agential, ontological, experiential, and fleshly being, thereby opening up future possibilities. We also think there is some urgency to this claim. For (...) many, faith in the rational human subject has been shattered by the events of twentieth and twenty-first centuries’ worldwide conflicts and increasing sectarianism. The concept of the subject as such is either obsolete or needs to be dynamically rethought. The current options appear to include resuscitating the rational liberal subject or agent, acknowledging limited agency in the performativity of language and gesture, or recognizing the agency of matter. We want to argue instead for a feminist phenomenological approach that begins with multiple, meaningful points of view on relational being. (shrink)

In recent years an uneasy peace has descended in U.S. academe between those who feel research universities have done too little to advance the representation of minority groups and women and those who feel that the administrative policies developed to improve representation can and sometimes do come into conflict with core intellectual commitments of universities. Using quantitative and qualitative evidence from interviews with 47 natural sciences, engineering, and mathematics faculty members at a U.S. research university, the paper examines the background (...) characteristics of three sets of protagonists - academic progressives, academic traditionalists, and those whose views bridge the divide - and the way respondents discussed and justified their viewpoints. The paper draws on the theory of strategic action fields to illuminate the structure and dynamics of the conflict and suggests modifications to the theory that would improve its explanatory power for this case. (shrink)

We describe the picture of physical processes suggested by Edward Nelson’s stochastic mechanics when generalized to quantum field theory regularized on a lattice, after an introductory review of his theory applied to the hydrogen atom. By performing numerical simulations of the relevant stochastic processes, we observe that Nelson’s theory provides a means of generating typical field configurations for any given quantum state. In particular, an intuitive picture is given of the field “beable”—to use a phrase of John Stewart Bell—corresponding to (...) the Fock vacuum, and an explanation is suggested for how particle-like features can be exhibited by excited states. We then argue that the picture looks qualitatively similar when generalized to interacting scalar field theory. Lastly, we compare the Nelsonian framework to various other proposed ontologies for QFT, and remark upon their relative merits in light of the effective field theory paradigm. Links to animations of the corresponding beables are provided throughout. (shrink)

Brown and Pooley’s ‘dynamical approach’ to physical theories asserts, in opposition to the orthodox position on physical geometry, that facts about physical geometry are grounded in, or explained by, facts about dynamical fields, not the other way round. John Norton has claimed that the proponent of the dynamical approach is illicitly committed to spatiotemporal presumptions in ‘constructing’ space-time from facts about dynamical symmetries. In this article, I present an abstract, algebraic formulation of field theories and demonstrate that the proponent (...) of the dynamical approach is not committed, in special relativity, to the illicit presumptions to which Norton refers. (shrink)

If we live on the weak brane with zero effective cosmological constant in a warped 5D bulk spacetime, gravitational waves and brane fluctuations can be generated by a part of the 5D Weyl tensor and carries information of the gravitational field outside the brane. We consider on a cylindrical symmetric warped FLRW background a U self-gravitating scalar field coupled to a gauge field without bulk matter. It turns out that brane fluctuations can be formed dynamically, due to the modified (...) energy–momentum tensor components of the scalar-gauge field. As a result, we find that the late-time behavior could significantly deviate from the standard evolution of the universe. The effect is triggered by the time-dependent warpfactor with two branches of the form \}\) constants) and the modified brane equations comparable with a dark energy effect. This is a brane-world mechanism, not present in standard 4D FLRW, where the large disturbances are rapidly damped as the expansion proceed. Because gravity can propagate in the bulk, the cosmic string can build up a huge angle deficit by the warpfactor and can induce massive KK-modes felt on the brane. Disturbances in the spatial components of the stress-energy tensor cause cylindrical symmetric waves, amplified due to the presence of the bulk space and warpfactor. They could survive the natural damping due to the expansion of the universe. It turns out that one of the metric components becomes singular at the moment the warp factor develops an extremum. This behavior could have influence on the possibility of a transition from acceleration to deceleration or vice versa. (shrink)

We propose a class of new gauge field models in 2n dimensions, with n not less than4. These systems are unrelated to Yang-Mills, in the sense that their gauge-field Higgs descendants in lower dimensions do not include the Yang-Mills dynamics.

The (Feynman) propagator G(x2,x1)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$G(x_2,x_1)$$\end{document} encodes the entire dynamics of a massive, free scalar field propagating in an arbitrary curved spacetime. The usual procedures for computing the propagator—either as a time ordered correlator or from a partition function defined through a path integral—requires introduction of a field ϕ(x)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\phi (x)$$\end{document} and its action functional A[ϕ(x)]\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} (...) \begin{document}$$A[\phi (x)]$$\end{document}. An alternative, more geometrical, procedure is to define a propagator in terms of the world-line path integral which only uses curves, xi(s)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$x^i(s)$$\end{document}, defined on the manifold. I show how the world-line path integral can be reinterpreted as an ordinary integral by introducing the concept of effective number of quantum paths of a given length. Several manipulations of the world-line path integral becomes algebraically tractable in this approach. In particular I derive an explicit expression for the propagator GQG(x2,x1)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$G_\mathrm{QG}(x_2,x_1)$$\end{document}, which incorporates the quantum structure of spacetime through a zero-point-length, in terms of the standard propagator Gstd(x2,x1)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$G_\mathrm{std}(x_2,x_1)$$\end{document}, in an arbitrary curved spacetime. This approach also helps to clarify the interplay between the path integral amplitude and the path integral measure in determining the form of the propagator. This is illustrated with several explicit examples. (shrink)

This paper takes a close look at a central aspect of the work of Peter Senge,1 namely his advocacy of the learning organisation and the ‘Communities of Commitment’ that he suggests are its central dynamic. Echoing strands of the liberal-communitarian debate, Senge argues for ‘the primacy of the whole’ and ‘the community nature of the self ’ as two of the three Galilean shifts2 which have the potential to enable business to accomplish fundamental changes in our ways of thinking and (...) being which have thus far eluded other agencies of social and political transformation. My concern is that Senge is not at all clear about the relationship between organisation and community, or, indeed, what community actually is. Arguing that his account is disappointingly partial and damagingly flawed, I then suggest a number of sites for future philosophical work for those who wish to develop an emancipatory notion of community. I end by advocating the work of John Macmurray as a major source of philosophical insight and human wisdom, both with regard to community and the development of a person-centred philosophy of work. A second paper will explore some of this ideas on these matters more fully.. (shrink)

We propose an adynamical, background independent approach to quantum gravity and unification whereby the fundamental elements of Nature are graphical units of space, time and sources. The transition amplitude for these elements of “spacetimesource” is computed using a path integral with discrete Gaussian graphical action. The unit of action for a spacetimesource element is constructed from a difference matrix K and source vector J on the graph, as in lattice gauge theory. K is constructed from graphical relations so that it (...) contains a non-trivial null space, and J is then restricted to the column space of K which ensures it is distributed in a divergence-free fashion over the spacetime defined by the element. This rule for the relational construct of K and J is our proposed fundamental axiom of physics and results in a self-consistency relationship between sources, the spacetime metric, and the stress-energy-momentum content of the element, rather than a dynamical law for time-evolved entities. In its most general form, the set of fundamental elements employed by lattice gauge theory contains scalar fields on nodes and links, and vector fields on nodes. To complete the fundamental set, we propose the addition of scalar fields on plaquettes and vector fields on links. We use this approach via modified Regge calculus to correct proper distance in the Einstein-deSitter cosmology model yielding a fit of the Union2 Compilation supernova data that matches ɅCDM without having to invoke accelerating expansion or dark energy. (shrink)

We consider a model of the state evolution of relativistic vector bosons, which includes both the dynamical equations for the particle four-velocity and the equations for the polarization four-vector evolution in the field of a nonlinear plane gravitational wave. In addition to the gravitational minimal coupling, tidal forces linear in curvature tensor are suggested to drive the particle state evolution. The exact solutions of the evolutionary equations are obtained. Birefringence and tidal deviations from the geodesic motion are discussed.

A (Higgs vacuum)–(spacetime geometry) reciprocity principle is proposed and its consequences are explored. While it has been established that configurations of the spacetime metric tensor field, associated with acceleration with respect to local inertial frames, cause the vacuum to become thermalized, it is asserted that the converse is also possible. An appropriate thermal vacuum, through dynamical mass generation, can cause particles to propagate in a spacetime with a Minkowski metric, as if they were in a spacetime with a non-Minkowski metric. (...) The two points of view are equivalent and interchangeable. Invoking the reciprocity principle in the case of the Unruh effect in an accelerated frame, a mechanism is analyzed whereby in the context of the minimal standard model a gradient in the vacuum expectation value of the Higgs field in the direction of acceleration produces an effective inertial force on an accelerated material body. (shrink)

This exploratory paper considers the concept of generation in the context of learning across the life course. Although researchers have often found considerable inequalities in participation by age, as well as strongly articulated attitudinal differences, there have so far been only a handful of studies that have explored these patterns through the perspective of generational formations. The paper is primarily conceptual, exploratory and reflective, setting out a number of approaches to the concept of generations, most of which derive largely from (...) debates with the ghost of Karl Mannheim; it then considers how these concepts of generation have been applied to understandings of educational inequalities in recent research in Germany and the Nordic nations. It then examines the dynamics of inter-generational relations in learning, drawing on research undertaken as part of the Teaching and Learning Research Programme. The paper argues that although inter-generational dynamics are a relatively neglected dimension of Anglophone research on life chances and learning, there is a strong case for understanding their dual roles in both inequality and cohesion. It concludes by outlining some themes and areas for further investigation in the future. (shrink)

A Higgsless model for strong, electroweak and gravitational interactions is proposed. This model is based on the local symmetry group SU(3)×SU(2)L×U(1)×C,where C is the local conformal symmetry group. The natural minimal conformally invariant form of total Lagrangian is postulated. It contains all standard model fields and gravitational interaction. Using the unitary gauge and the conformal scale fixing conditions, we can eliminate all four real components of the Higgs doublet in this model. However, the masses of vector mesons, leptons, and (...) quarks are automatically generated and are given by the same formulas as in the conventional standard model. In this manner one gets the mass generation without the mechanism of spontaneous symmetry breaking and without the remaining real dynamical Higgs field. The gravitational sector is analyzed, and it is shown that the model admits in the classical limit the Einsteinian form of gravitational interactions. (shrink)

As we know, Merleau-Ponty was struggling with a dynamic shift in his thinking at the premature end of his life. In those last notes he raises the question of how to elaborate a phenomenology of “’the other world’, as the limit of a phenomenology of the imaginary and the ‘hidden’”—a phenomenology that would open onto an invisible life, community, other and culture. In her essay on “Eye and Mind”, “To Paint the Invisible”, Luce Irigaray argues that Merleau-Ponty was not yet (...) ready to address this question, of the limits posed to his vision by the presence of an other. The artworks of abstract expressionist artist Joan Mitchell are considered in the ways that they open up a different time-space suggesting an other world with which we intertwine without appropriation. Her works, I argue, defy reduction to essences, but also do not rely merely on sensation—for this reason they point in the direction of how to think phenomenology anew. For I do think Merleau-Ponty would be open to these conversations, to these other worlds and other visions. (shrink)

How does conscious thought occur? In the scene 'The cat is next to the dog', the cat is within a proximal distance to the left or right of the dog. This probabilistic proximal left/right cognitive space is an example of a mental 'place field'. A place field -- also in humans presumably represented by place cells in the hippocampus -- represents latent and thus potentially unconscious thought. Mentally 'seeing' the cat to the left or right is an example of a (...) 'localized point' within a place field. A localized point represents manifest and thus conscious thought. As proposed, this field-to-point reduction is naturally described in terms of force dynamics, a prominent theory of causal cognition. Possible generalizations from spatial mental imagery to all conscious occurrences of thought and emotion are discussed. (shrink)

Classical and quantum field theory provide not only realistic examples of extant notions of empirical equivalence, but also new notions of empirical equivalence, both modal and occurrent. A simple but modern gravitational case goes back to the 1890s, but there has been apparently total neglect of the simplest relativistic analog, with the result that an erroneous claim has taken root that Special Relativity could not have accommodated gravity even if there were no bending of light. The fairly recent acceptance of (...) nonzero neutrino masses shows that widely neglected possibilities for nonzero particle masses have sometimes been vindicated. In the electromagnetic case, there is permanent underdetermination at the classical and quantum levels between Maxwell's theory and the one-parameter family of Proca's electromagnetisms with massive photons, which approximate Maxwell's theory in the limit of zero photon mass. While Yang–Mills theories display similar approximate equivalence classically, quantization typically breaks this equivalence. A possible exception, including unified electroweak theory, might permit a mass term for the photons but not the Yang–Mills vector bosons. Underdetermination between massive and massless (Einstein) gravity even at the classical level is subject to contemporary controversy. (shrink)

Hamiltonian light-front dynamics of quantum fields may provide a useful approach to systematic nonperturbative approximations to quantum field theories. We investigate inequivalent Hilbert-space representations of the light-front field algebra in which the stability group of the light front is implemented by unitary transformations. The Hilbert space representation of states is generated by the operator algebra from the vacuum state. There is a large class of vacuum states besides the Fock vacuum which meet all the invariance requirements. The light-front (...) Hamiltonian must annihilate the vacuum and have a positive spectrum. We exhibit relations of the Hamiltonian to the nontrivial vacuum structure. (shrink)

A mechanism describing state reduction dynamics in relativistic quantum field theory is outlined. The mechanism involves nonlinear stochastic modifications to the standard description of unitary state evolution and the introduction of a relativistic field in which a quantized degree of freedom is associated to each point in spacetime. The purpose of this field is to mediate in the interaction between classical stochastic influences and conventional quantum fields. The equations of motion are Lorentz covariant, frame independent, and do not (...) result in divergent behavior. It is shown that the mathematical framework permits the specification of unambiguous local properties providing a connection between the model and evidence of real world phenomena. The collapse process is demonstrated for an idealized example. (shrink)

As research on mind wandering has accelerated, the construct’s defining features have expanded and researchers have begun to examine different dimensions of mind wandering. Recently, Christoff and colleagues have argued for the importance of investigating a hitherto neglected variety of mind wandering: “unconstrained thought,” or, thought that is relatively unguided by executive-control processes. To date, with only a handful of studies investigating unconstrained thought, little is known about this intriguing type of mind wandering. Across two experiments, we examined, for the (...) first time, whether changes in task demand influence rates of constrained versus unconstrained thoughts. In both experiments, participants completed either an easy (0-back) or hard (2-back) task and responded to intermittently presented thought probes that gauged thought constraint throughout the task. In Experiment 1, we found that participants completing the easy task engaged in unconstrained thoughts more frequently than those completing the difficult task. In Experiment 2, we replicated this result and further demonstrated manipulations of unconstrained thought while also measuring task-relatedness (a common dimension of mind wandering). Finally, exploratory analyses showed associations between constrained thought and age, verbal intelligence, and an assessment of flow (‘deep effortless concentration’), thereby adding further evidence to indicate a dissociation between task-relatedness and constraint. We discuss the methodological and theoretical applications of our findings to the burgeoning field of research on unconstrained thought. (shrink)

Recent investigation on the short-time dynamic scaling of critical dynamics is reviewed, with the aim of applying it to the field theory. The contents of this paper are as follows: (1) Short-time behavior of the critical relaxation dynamics, (2) Numerical evidence of the short-time scaling—2-dimensional Ising model and Universality, (3) Theoretical background of the generalized scaling form, (4) Application to a field theoretical model—(2+1)-dimensional SU(2) lattice gauge theory at finite temperature, and (5) Concluding remarks.

The phenomenon of entrepreneurship has attracted researchers from a variety of disciplines and a diverse number of analytical approaches. Currently, there is a considerable amount of confusion and a variety of conflicting theories which are being used interchangeably and ambiguously. In this important new book, the authors argue that there are analytically distinct forms of entrepreneurship, each of them having an individual logic of their own. They highlight the role of individual economic agents with endowments of new knowledge or new (...) combinations of old knowledge as entrepreneurs, and thus identify them as dynamic factors in the knowledge economy. Overall, this book not only provides a contemporary overview of current research in the field, but also summarizes the policy conclusions that can be drawn from current research. (shrink)

The wave function and spin are shown to be attributes of the dynamics which is a dominant structure of the quantum mechanics. A self-consistent force field κ (not the quantum axiomatics) appears to be responsible for quantum effects. The field κ can escape from the matter and produce pairs.

Protein structure is dynamic: the intrinsic flexibility of polypeptides facilitates a range of conformational fluctuations, and individual protein chains can assemble into complexes. Proteins are also dynamic in evolution: significant variations in secondary, tertiary and quaternary structure can be observed among divergent members of a protein family. Recent work has highlighted intriguing similarities between these structural and evolutionary dynamics occurring at various levels. Here we review evidence showing how evolutionary changes in protein sequence and structure are often closely related (...) to local protein flexibility and disorder, large‐scale motions and quaternary structure assembly. We suggest that these correspondences can be largely explained by neutral evolution, while deviations between structural and evolutionary dynamics can provide valuable functional insights. Finally, we address future prospects for the field and practical applications that arise from a deeper understanding of the intimate relationship between protein structure, dynamics, function and evolution. (shrink)

Shifts are a well-known feature of the literature on spacetime symmetries. Recently, discussions have focused on so-called dynamic shifts, which by analogy with static and kinematic shifts enact arbitrary linear accelerations of all matter (as well as a change in the gravitational potential). But in mathematical formulations of these shifts, the analogy breaks down: while static and kinematic shift act on the matter field, the dynamic shift acts on spacetime structure instead. I formulate a different, `active' version of the dynamic (...) shift which does act on matter. (shrink)

The potential of a static electric charge located in a Schwarzschild gravitational field is given by Linet. The expressions for the field lines derived from this potential are calculated by numerical integration and drawn for different locations of the static charge in the gravitational field. The field lines calculated for a charge located very close to the central mass can be compared to those calculated by Hanni–Ruffini. Maxwell equations are used to analyze the dynamics of the falling electric field (...) in a gravitational field. (shrink)

This thesis is on information dynamics modeled using *dynamic epistemic logic*. It takes the simple perspective of identifying models with maps, which under a suitable topology may be analyzed as *topological dynamical systems*. It is composed of an introduction and six papers. The introduction situates DEL in the field of formal epistemology, exemplifies its use and summarizes the main contributions of the papers.Paper I models the information dynamics of the *bystander effect* from social psychology. It shows how augmenting (...) the standard machinery of DEL with a decision making framework yields mathematically self-contained models of dynamic processes, a prerequisite for rigid model comparison.Paper II extrapolates from Paper I's construction, showing how the augmentation and its natural peers may be construed as maps. It argues that under the restriction of dynamics produced by DEL dynamical systems still falls a collection rich enough to be of interest. Paper III compares the approach of Paper II with *extensional protocols*, the main alternative augmentation to DEL. It concludes that both have benefits, depending on application. In favor of the DEL dynamical systems, it shows that extensional protocols designed to mimic simple, DEL dynamical systems require infinite representations. Paper IV focuses on *topological dynamical systems*. It argues that the *Stone topology* is a natural topology for investigating logical dynamics as, in it, *logical convergence* coinsides with topological convergence. It investigates the recurrent behavior of the maps of Papers II and III, providing novel insigths on their long-term behavior, thus providing a proof of concept for the approach.Paper V lays the background for Paper IV, starting from the construction of metrics generalizing the Hamming distance to infinite strings, inducing the Stone topology. It shows that the Stone topology is unique in making logical and topological convergens coinside, making it the natural topology for logical dynamics. It further includes a metric-based proof that the hitherto analyzed maps are continuous with respect to the Stone topology. Paper VI presents two characterization theorems for the existence of *reduction laws*, a common tool in obtaining complete dynamic logics. In the compact case, continuity in the Stone topology characterizes existence, while a strengthening is required in the non-compact case. The results allow the recasting of many logical dynamics of contemporary interest as topological dynamical systems. (shrink)

Two of the world's leading astrophysicists, James Binney and Scott Tremaine, here present a comprehensive review of the theory of galactic dynamics at a level suitable for both graduate students and researchers. Their work in this volume describes our present understanding of the structure and dynamics of stellar systems such as galaxies and star clusters. Nicknamed "the Bible of galactic dynamics," this book has become a classic treatise, well known and widely used by researchers and students of (...) galactic astrophysics and stellar dynamics. Praised for its modern approach, as well as for the rigor and exemplary clarity with which the authors handle the material in this book, Galactic Dynamics includes classic results and data while also reflecting the many recent developments in the field. The authors maintain an effective style of exposition throughout, keeping clear what is present knowledge and what is still speculation, while allowing the reader to grasp an overview of the subject before following through with the mathematical detail. Most of the astronomical community since the late 1980s was introduced to galactic dynamics through Galactic Dynamics, and it remains the most widely used graduate textbook in galactic astrophysics today. No other book gathers together and presents our current understanding of the field in such a clear and concise way. Through this approach, Binney and Tremaine succeeded in creating a classic reference of enormous pedagogic value. (shrink)

We give a general method for producing various effective Null and Positivstellensätze, and getting new Positivstellensätze in algebraically closed valued fields and ordered groups. These various effective Nullstellensätze produce algebraic identities certifying that some geometric conditions cannot be simultaneously satisfied. We produce also constructive versions of abstract classical results of algebra based on Zorn's lemma in several cases where such constructive version did not exist. For example, the fact that a real field can be totally ordered, or the fact (...) that a field can be embedded in an algebraically closed field. Our results are based on the concepts we develop of dynamical proofs and simultaneous collapse. (shrink)

Dynamic algebras combine the classes of Boolean (B 0) and regular (R ; *) algebras into a single finitely axiomatized variety (B R ) resembling an R-module with scalar multiplication . The basic result is that * is reflexive transitive closure, contrary to the intuition that this concept should require quantifiers for its definition. Using this result we give several examples of dynamic algebras arising naturally in connection with additive functions, binary relations, state trajectories, languages, and flowcharts. The main (...) result is that free dynamic algebras are residually finite (i.e. factor as a subdirect product of finite dynamic algebras), important because finite separable dynamic algebras are isomorphic to Kripke structures. Applications include a new completeness proof for the Segerberg axiomatization of prepositional dynamic logic, and yet another notion of regular algebra. (shrink)

Stakeholder literature tends to presume that effective stakeholder dialogue, occurring directly or indirectly, among a focal firm, local communities, governments, and nongovernmental organizations is desirable for successful firm–stakeholder relationships. Even if theoretically desirable, effective dialogue does not always occur. There are two key theory-informing lessons in Botnia’s Fray Bentos successful green field pulp mill investment and start-up in Western Uruguay. First, critics could not halt the project politically supported by Uruguay in an expanding multi-party international dispute. Second, the Botnia corporate (...) communications process did not succeed in building consensus relationships, and attention was not paid to discourse creating shared meanings among all stakeholders. Participatory relationships were few, and successful dialogue was at best limited to supporters. This article uses discursive analysis to examine how newspaper and press release texts and language used therein both shaped and reflected the dynamically changing nature of firm–stakeholder relations in the Fray Bentos dispute. Despite the focal firm’s professed good intentions to create participatory relationships with its stakeholders during the building project, various stakeholders opposed the project and Botnia was caught in the crossfire of heated debate between Uruguay and Argentina. Three different frames changing over time are identified: the investment frame, the conflict frame, and the political frame. The analysis shows that the relationships between the focal firm and stakeholders involved many meanings only partly shared, due in part to a lack of corporate appreciation for the role of language in managing firm–stakeholder relationships. (shrink)