This useful anthology comprises seventy-nine selections arranged under three headings. Part I is titled "Ancient and Classical Ideas of Space"; part II, "The Classical and Ancient Concepts of Time"; part III, "Modern Views of Space and Time and their Anticipations." According to the general editors of the Boston series, R. S. Cohen and Marx W. Wartofsky, Capek’s choice of contents was governed by the desire to show that "parts of our view of nature greatly and mutually influence other parts, and (...) that our conception of the world keeps evolving. Thus, ideas of time intertwine with ideas of space, and both with ideas of matter and force." F. M. Cornford’s essays, "The Invention of Space" and "The Elimination of Time by Parmenides," introduce parts I and II respectively. In part I, while Descartes, Pascal, Gassendi, Newton, etc., speak for themselves, the ancients and medievals are given other mouthpieces—Duhem’s monumental Le système du monde, for Plato, Aristotle, and the medievals; C. Bailey, for Leucippus, Epicurus and Lucretius; Koyré, Höffding, Jammer, for the period from Bradwardine to William Gilbert. On the subject of time, however, both ancient and classical authors are allowed to express their opinions in their own words, with the understandable exception of the Stoics. Part III begins with the prerelativistic critique of Newton as well as the well-known Clarke-Leibniz discussion on the nature of space and time. This third part, however, is dominated largely by the implications of Einstein’s general and special relativity theories. For instance, we have Minkowski’s "Union of Space and Time." Four items, at least, are devoted to the twin-paradox. Some argue for a static, subjective, or even idealistic conception of space-time whereas positivists like Frank attack Sir James Jeans’ and other idealistic interpretations of relativity as instances of meaningless metaphysics. Part III concludes with Weyl’s objectivistic interpretation of quantum-mechanical indeterminacy. While it is difficult to find an anthology that will please all readers or teachers, this work goes far towards dealing comprehensively with the subject of space and time. As Cohen and Wartofsky note, what is distinctive of Capek’s approach within the field of philosophy of nature and its history is that "he is greatly appreciative of Bergson, James, Peirce and Whitehead" and though influenced by them, he is also critical because of the "understanding of the philosophical import that contemporary physics brings into our picture of the world." In a lengthy introduction, the editor explains his rationale for each item he includes. In general this is very helpful, but in some instances the suggested historical connections are misleading at best, if not simply false or questionable. Einstein for instance is said to have "rejected any absolute frame of reference which would be a substrate of absolutely simultaneous events... within the context of Michelson’s vain search for the absolute motion of the earth." This seems to imply—as many others have claimed—that the negative results of the ether-drift experiment influenced Einstein in formulating his relativity theory, whereas historians have pointed out that if Einstein referred to the experiment, it would have to be as a confirmation of his theory, since he did not learn of the results obtained by Michelson and Morley until after the publication of his revolutionary paper in 1905. Though there are other generalizations in the introduction which might be open to dispute, Capek’s prefatory remarks are in general helpful, and the essay collection as a whole stands on its own feet. It is valuable, if for no other reason, that a number of the selections appear in English translation for the first time.—A.B.W. (shrink)

© 2015 American Chemical Society.Polarized aluminum K-edge X-ray absorption near edge structure spectroscopy and first-principles calculations were used to probe electronic structure in a series of Al, AlX 2, and AlR 2 coordination compounds. Spectral interpretations were guided by examination of the calculated transition energies and polarization-dependent oscillator strengths, which agreed well with the XANES spectroscopy measurements. Pre-edge features were assigned to transitions associated with the Al 3p orbitals involved in metal-ligand bonding. Qualitative trends in Al 1s core energy and (...) valence orbital occupation were established through a systematic comparison of excited states derived from Al 3p orbitals with similar symmetries in a molecular orbital framework. These trends suggested that the higher transition energies observed for AlX 2 systems with more electronegative X 1- ligands could be ascribed to a decrease in electron density around the aluminum atom, which causes an increase in the attractive potential of the Al nucleus and concomitant increase in the binding energy of the Al 1s core orbitals. For Al and AlH 2 the experimental Al K-edge XANES spectra and spectra calculated using the eXcited electron and Core-Hole approach had nearly identical energies for transitions to final state orbitals of similar composition and symmetry. These results implied that the charge distributions about the aluminum atoms in Al and AlH 2 are similar relative to the AlX 2 and AlMe 2 compounds, despite having different formal oxidation states of +1 and +3, respectively. However, Al was unique in that it exhibited a low-energy feature that was attributed to transitions into a low-lying p-orbital of b 1 symmetry that is localized on Al and orthogonal to the Al plane. The presence of this low-energy unoccupied molecular orbital on electron-rich Al distinguishes its valence electronic structure from that of the formally trivalent compounds AlX 2 and AlR 2. The work shows that Al K-edge XANES spectroscopy can be used to provide valuable insight into electronic structure and reactivity relationships for main-group coordination compounds. (shrink)

The structure of the thermal equilibrium state of a weakly interacting Bose gas is of current interest. We calculate the density matrix of that state in two ways. The most effective method, in terms of yielding a simple, explicit answer, is to construct a generating function within the traditional framework of quantum statistical mechanics. The alternative method, arguably more interesting, is to construct the thermal state as a vector state in an artificial system with twice as many degrees of freedom. (...) It is well known that this construction has an actual physical realization in the quantum thermodynamics of black holes, where the added degrees of freedom correspond to the second sheet of the Kruskal manifold and the thermal vector state is a state of the Unruh or the Hartle–Hawking type. What is unusual about the present work is that the Bogolubov transformation used to construct the thermal state combines in a rather symmetrical way with Bogolubov's original transformation of the same form, used to implement the interaction of the nonideal gas in linear approximation. In addition to providing a density matrix, the method makes it possible to calculate efficiently certain expectation values directly in terms of the thermal vector state of the doubled system. (shrink)

The central idea of this paper is that forming the black hole horizon is attended with the transition from the classical regime of evolution to the quantum one. We offer and justify the following criterion for discriminating between the classical and the quantum: creations and annihilations of particle-antiparticle pairs are impossible in the classical reality but possible in the quantum reality. In flat spacetime, we can switch from the classical picture of field propagation to the quantum picture by changing the (...) overall sign of the spacetime signature. To describe a self-gravitating object at the final stage of its classical evolution, we propose to use the Foldy–Wouthuysen representation of the Dirac equation in curved spacetimes, and the Gozzi classical path integral. In both approaches, maintaining the dynamics in the classical regime is controlled by supersymmetry. (shrink)

We present a framework for analyzing black hole backreaction from the point of view of quantum open systems using influence functional formalism. We focus on the model of a black hole described by a radially perturbed quasi-static metric and Hawking radiation by a conformally coupled massless quantum scalar field. It is shown that the closed-time-path (CTP) effective action yields a non-local dissipation term as well as a stochastic noise term in the equation of motion, the Einstein–Langevin equation. Once the thermal (...) Green's function in a Schwarzschild background becomes available to the required accuracy, the strategy described here can be applied to obtain concrete results on backreaction. We also present an alternative derivation of the CTP effective action in terms of the Bogolyubov coefficients, thus making a connection with the interpretation of the noise term as measuring the difference in particle production in alternative histories. (shrink)

We discuss some recent work by Tim Maudlin concerning Black Hole Information Loss. We argue, contra Maudlin, that there is a paradox, in the straightforward sense that there are propositions that appear true, but which are incompatible with one another. We discuss the significance of the paradox and Maudlin's response to it.

It is commonly assumed that low-mass primordial black holes cannot constitute a significant fraction of the dark matter in our universe due to their predicted short lifetimes from the conventional Hawking radiation and evaporation process. Assuming physical black holes are nonsingular--likely due to quantum gravity or other high-energy physics--we demonstrate that a large class of nonsingular black holes have finite evaporation temperatures. This can lead to slowly evaporating low-mass black holes or to remnant mass states that (...) circumvent traditional evaporation constraints. As a proof of concept, we explore the limiting curvature hypothesis and the evaporation process of a nonsingular black hole solution in two-dimensional dilaton gravity. We identify generic features of the radiation profile and compare them with known regular black holes, such as the Bardeen solution in four dimensions. Remnant masses are proportional to the fundamental length scale, and we argue that slowly evaporating low-mass nonsingular black holes, or remnants, are viable dark matter candidates. (shrink)

Computer vision research involving street and road detection methods usually focuses on driving assistance and autonomous vehicle systems. In this context, street segmentation occurs in real-time, based on images centered on the street. This work, on the other hand, uses street segmentation for urban planning research to classify pavement types of a city or region, which is particularly important for developing countries. For this application, it is needed a dataset with images from various locations for each street. These images are (...) not necessarily centered on the street and include challenges that are not common in street segmentation datasets, such as mixed pavement types and the presence of faults and holes on the street. We implemented a multi-class version of a state-of-the-art segmentation algorithm and adapted it to perform street pavement classification, handling navigation along streets and angle variation to increase the accuracy of the classification. A data augmentation approach is also proposed to use preliminary results from the test instances as new ground truth and increase the amount of training data. A dataset with more than 300,000 images from 773 streets from a Brazilian city was built. Our approach achieved a precision of 0.93, showing the feasibility of the proposed application. (shrink)

BACKGROUND: Hallucinations and delusions that complicate Parkinson’s disease could lead to nursing home placement and are linked to increased mortality. Cognitive impairments are typically associated with the presence of hallucinations but there are no data regarding whether such a relationship exists with delusions. OBJECTIVE: We hypothesized that hallucinations would be associated with executive and visuospatial disturbance. An exploratory examination of cognitive correlates of delusions was also completed to address the question of whether they differ from hallucinations. METHODS: 144 PD subjects (...) completed a neuropsychological battery to assess cognition and the SAPS to examine psychosis. Correlational analyses assessed associations between hallucinations and delusions with cognitive domains. RESULTS: 48 subjects reported psychotic symptoms: 25 experienced hallucinations without delusions, 23 had symptoms dominated by delusions. Severity and/or number of hallucination subtypes were significantly correlated with lower scores in language, memory, attention, executive functioning, and visuospatial ability. Correlations with delusions were non-significant. Tests of differences in the size of the correlations between groups revealed a significant relationship between language and visuospatial performance with hallucinations. CONCLUSIONS: Cognitive correlates of hallucinations and delusions appear to be different in PD, suggesting distinct pathogenic mechanisms and possibly anatomical substrates. Hence, delusions may not share the same associations with dementia as hallucinations. Since this is a new finding, further studies will be needed to confirm our results. (shrink)

Stephen Hawking is well known for his research on general relativity and black holes. The present work is his attempt to explain his research in a form intelligible to the nonspecialist.

This is in memoriam of Robert (Bob) C. Solomon from the University of Texas at Austin, a great philosopher, teacher, and friend.

There is evidence of reciprocal connectivity, similarity of oscillatory responses to stimulation of multiple motor and somatosensory cortices, whole system oscillation, and short- latency responses to behavioral perturbation. These suggest that frame/content may be instantiated by overlapping neural populations, and that the genesis of frame oscillations may be profitably thought of as an emergent property of a distributed neural system.

. Ably marshalling ideas from theology, philosophy, and neurology, personality theorist Joseph F. Rychlak criticizes mechanistic psychologists' neglect of will and responsibility; these human qualities involve dialectically considering alternatives. I disagree with Rychlaks suggestion of fundamental mystery in the minds transcendence of the body and believe transcendent mind is intimately related to biological evolution and the brain. For example, dialectics, seen in simpler forms in lower animals, may require neural inhibition, feedback circuits, and topographic mappings. However, epistemologically speaking, neuroscientists strongly (...) need the human insights of work such as Rychlak's to understand the alternatives, in planning investigation at more microscopic levels. (shrink)

We analyze the rather unusual properties of some exact solutions in 2D dilaton gravity for which infinite quantum stresses on the Killing horizon can be compatible with regularity of the geometry. In particular, the Boulware state can support a regular horizon. We show that such solutions are contained in some well-known exactly solvable models (for example, RST). Formally, they appear to account for an additional coefficient B in the solutions (for the same Lagrangian which contains also “traditional” solutions) that gives (...) rise to the deviation of temperature T from its Hawking value T H . The Lorentzian geometry, which is a self-consistent solution of the semiclassical field equations, in such models, is smooth even at B≠0 and there is no need to put B=0 (T=T H ) to smooth it out. We show how the presence of B≠0 affects the structure of spacetime. In contrast to “usual” black holes, full fledged thermodynamic interpretation, including definite value of entropy, can be ascribed (for a rather wide class of models) to extremal horizons, not to nonextreme ones. We find also new exact solutions for “usual” black holes (with T=T H ). The properties under discussion arise in the weak-coupling regime of the effective constant of dilaton-gravity interaction. Extension of features, traced in 2D models, to 4D dilaton gravity leads, for some special models, to exceptional nonextreme black holes having no own thermal properties. (shrink)

The neural basis of human memory is incredibly complex. We argue that the diversity of neural systems underlying various forms of memory suggests that any discussion of enhancing ‘memory’ per se is too broad, thus obfuscating the biopolitical debate about human enhancement. Memory can be differentiated into at least four major systems with largely dissociable neural substrates. We outline each system, and discuss both the practical and the ethical implications of these diverse neural substrates. In practice, distinct neural bases imply (...) the possibility, and likely the necessity, of specific approaches for the safe and effective enhancement of various memory systems. In the debate over the ethical and social implications of enhancement technologies, this fine-grained perspective clarifies—and may partially mitigate—certain common concerns in enhancement debates, including issues related to safety, fairness, coercion, and authenticity. While many researchers certainly appreciate the neurobiological complexity of memory, the political debate tends to revolve around a monolithic one-size-fits-all conception. The overall project—exploring how human enhancement technologies affect society – stands to benefit from a deeper appreciation of memory’s neurobiological diversity. (shrink)

A tight control of intracellular [Ca2+\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^{2+}$$\end{document}] is essential for the survival and normal function of cells. In this study we investigate key mechanistic steps by which calcium is regulated and calcium oscillations could occur using in silico modeling of membrane transporters. To do so we give a deterministic description of intracellular Ca2+\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^{2+}$$\end{document} dynamics using nonlinear dynamics in order to understand Ca2+\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} (...) \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^{2+}$$\end{document} signaling. We first present the ordinary differential equations (ODEs) system for cell calcium kinetics and make a preliminary work on Sobol indices. We then describe and analyze complex transporters action. Besides, we analyze the whole system. We finally perform numerical simulations and compare our results to real data. (shrink)

Pothos & Busemeyer (P&B) argue that classical probability (CP) fails to describe human decision processes accurately and should be supplanted by quantum probability. We accept the premise, but reject P&B's conclusion. CP is a prescriptive framework that has inspired a great deal of valuable research. Also, because CP is used across the sciences, it is a cornerstone of interdisciplinary collaboration.

We show a sense in which the spacetime property of effective completeness—a type of “local hole-freeness” or “local inextendibility”—is not stable.

Determinism is the thesis that the past determines the future, but efforts to define it precisely have exposed deep methodological disagreements. Standard possible-worlds formulations of determinism presuppose an "agreement" relation between worlds, but this relation can be understood in multiple ways -- none of which is particularly clear. We critically examine the proliferation of definitions of determinism in the recent literature, arguing that these definitions fail to deliver clear verdicts about actual scientific theories. We advocate a return to a formal (...) approach, in the logical tradition of Carnap, that treats determinism as a property of scientific theories, rather than an elusive metaphysical doctrine. We highlight two key distinctions: (1) the difference between qualitative and "full" determinism, as emphasized in recent discussions of physics and metaphysics, and (2) the distinction between weak and strong formal conditions on the uniqueness of world extensions. We argue that defining determinism in terms of metaphysical notions such as haecceities is unhelpful, whereas rigorous formal criteria -- such as Belot's D1 and D3 -- offer a tractable and scientifically relevant account. By clarifying what it means for a theory to be deterministic, we set the stage for a fruitful interaction between physics and metaphysics. (shrink)

Mind uploading speculation and debate often concludes that a procedure described as gradual in-place replacement preserves personal identity while a procedure described as destructive scan-and-copy produces some other identity in the target substrate such that personal identity is lost along with the biological brain. This paper demonstrates a chain of reasoning that establishes metaphysical equivalence between these two methods in terms of preserving personal identity.

I describe how gravitational entropy is intimately connected with the concept of gravitational heat, expressed as the difference between the total and free energies of a given gravitational system. From this perspective one can compute these thermodyanmic quantities in settings that go considerably beyond Bekenstein's original insight that the area of a black hole event horizon can be identified with thermodynamic entropy. The settings include the outsides of cosmological horizons and spacetimes with NUT charge. However the interpretation of gravitational entropy (...) in these broader contexts remains to be understood. (shrink)

This brief paper shows how an exact analogue of Einstein's original hole argument can be constructed in the loop representation of quantum gravity. The new argument is based on the embedding of spin-networks in a manifold and the action of the diffeomorphism constraint on them. The implications of this result are then discussed. I argue that the conclusions of many physicists working on loop quantum gravity---Rovelli and Smolin in particular---that the loop representation uniquely supports relationalism are unfounded.

Doubts are raised concerning Rickles' claim that ``an exact analog of the hole argument can be constructed in the loop representation of quantum gravity'' (Rickles, `A new spin on the hole argument', Studies in History and Philosophy of Modern Physics 36 (2005) 415–434).

Religion persists, even within enlightened secular society, because it has adaptive functions. In particular, Ralph Wendell Burhoe's theory holds that religion is the repository of cultural wisdom that most encourages mutual altruism among nonkin, long-term social survival, and human progress. This article suggests a variant of Burhoe's rationalized naturalistic view. Cognitive theism is a proposal that secularists sometimes take religion on its own terms by suspending disbelief about God. If we consider particular human capacities and limitations in memory, perception, personality, (...) and motivation, the regulated “mind expansion” of cognitive theism may help us to evaluate, coordinate, and invigorate things in a modern environment. In this environment, communicative and travel technologies have led to a high loading of consciousness with a historically unusual diverse range of experiences and responsibilities, a high rate of cultural change relative to biological evolution, and a tendency to factionalize. Burhoe's extension of the concept of symbiosis to the coevolution of culture and genes is modified here in recognition of individual differences and of individuals' potential for choosing strategies, recombining in groups, and learning. In human biocultural symbiont pools, cultural phenomena can evolve while changing partners in a dance with genetic substrates, a dance that broadly supports these substrates. In the context of diversity and incessant change in a large predominantly secular community, Judeo-Christian monotheism can have a valuable advisory unifying function. (shrink)

Clambering down slippery rocks to a swimming hole. Ducking the plume of smoke from a barbecue grill. Wishing for a breeze in a too-small dome tent. Scanning the sky for rain from a postage-stamp backyard. It is in these small moments of action—and inaction—that Justin Kimball captures our everyday attempts to relax. Indeed, one might argue that the events depicted are everyday life. Kimball’s compelling photographs depict ordinary people—parents and teens, grandparents and kids—in landscapes of leisure. These are not the (...) exclusive resorts and white sand beaches of the affluent; rather, they are the parks, campgrounds, and fishing piers where most Americans vacation. They are natural landscapes—inviting, green, and sometimes beautiful—but at the same time they are imperfect—muddy, crowded, and partially paved. There is nothing idyllic about these vacation spots; indeed, Kimball’s photographs make clear that daily life can never be fully left behind. The people in his pictures, though momentarily transformed by cascading water or the shade of towering trees, remain enmeshed in ties of family and obligation, shadowed by thoughts of home. It is Kimball’s particular genius to isolate these moments between duty and pleasure. Where We Find Ourselves enables viewers to identify with—and participate in—this bittersweet aspect of American leisure and the ambiguous contemporary relationship between people and nature. (shrink)

Most early studies of consciousness have focused on human subjects. This is understandable, given that humans are capable of reporting accurately the events they experience through language or by way of other kinds of voluntary response. As researchers turn their attention to other animals, “accurate report” methodologies become increasingly difficult to apply. Alternative strategies for amassing evidence for consciousness in non-human species include searching for evolutionary homologies in anatomical substrates and measurement of physiological correlates of conscious states. In addition, creative (...) means must be developed for eliciting behaviors consistent with consciousness. In this paper, we explore whether necessary conditions for consciousness can be established for species as disparate as birds and cephalopods. We conclude that a strong case can be made for avian species and that the case for cephalopods remains open. Nonetheless, a consistent effort should yield new means for interpreting animal behavior. (shrink)

This work develops a systematic Hegelian critique of Advaita Vedānta’s doctrine of pure consciousness (śuddha-caitanya), diagnosing its central non-dual claim as a case of hypostatized abstraction—treating the conceptual product of reflection as though it were the primordial ground of reality. Through five interconnected problems (immediacy, identity, totality, negation, and temporality), the analysis shows how Vedānta abstracts “consciousness-in-general” from determinate acts of consciousness and then reverses the logical order by claiming that concrete particulars derive from this abstract universal. The error functions (...) like the “missing dollar” puzzle: a miscount produced by treating what is already included as though it were an additional remainder. Drawing on Hegel’s Science of Logic and Lacanian signifier theory, the work argues that this is not Vedānta’s isolated mistake but a recurrent temptation of reflective thought—one that reappears in contemporary philosophy of mind. The same structure animates debates about AI consciousness, panpsychism, and the hard problem, where abstractions (“phenomenal character,” “proto-consciousness,” “what-it’s-like”) are then reified into metaphysical substances. The constructive alternative reconceives consciousness as self-relating activity: the temporal movement through which living beings differentiate themselves, return to themselves, and thereby achieve self-awareness. This framework preserves the genuine insights of contemplative practice while dissolving the metaphysical confusions that absolutize them. Consciousness requires no transcendent substrate; properly understood, finitude is its only possible concrete unity. (shrink)

Part I of this two-part paper provided a broad overview of clinical and experimental findings bearing on the neural correlates of conscious processes. It was argued that several neurocognitive models related to: orienting to the outer world, dream sleep, and the integration of sensory-motor representations, converge upon a core ‘conscious system’, dubbed the extended reticular-thalamic activating system . The functions of the ERTAS, which shares extensive projections with the cerebral cortex, are mostly ‘implicit’, in contrast to the explicit representation of (...) conscious content within the neocortex. Part II expands this ERTAS model to encompass: the generation of coherent patterns of EEG activation, the integration of distributed cortical processes into a stream of unified percepts , and selective attention, as well as links between the ERTAS and systems providing the neural substrates for episodic memory and volition. (shrink)

Places is a Features column presenting descriptions of and reports on major research institutes in biology. Previous articles have dealt with, amongst other institutions, the Imperial Cancer Research Fund, the Marine Biological Laboratory at Woods Hole, the John Innes Institute, and the Department of Embryology of the Carnegie Institute. In the following article, Irving B. Fritz reviews the history and present program of one of Canada's outstanding institutions, the Banting and Best Department of Medical Research of the University of Toronto.

In the long journey of the human mind attempting to decode the workings of reality, one trusted companion has to be abandoned: the materialistic and reductionistic scientific worldviewWorldviewmaterialistic and reductionistic scientific. What new notion should fill the void? Slowly a novel worldview is emerging, supported by different theoretical traditions. Most intriguingly, at the nexus of these formal approaches a new ontology of reality is becoming most apparent. Two novel mantras are spreading through humanity’s collective mind: Information is physical “Information is (...) physical” and “Information represents the ultimate natureNature of reality of reality.” These surprisingly simple assertions have many deep consequences. Information theory is the wellspring of our contemporary digital world. Computation is, in essence, information processing. Then, information can be harnessed for mechanical work. Moreover, some of the pioneers of modern theoretical physics have, for a long time, suspected that information plays a fundamental role in nature. One striking consequence of this paradigm is that reality is inherently finite. Infinities can only be found in the abstract thought systems of the human mindHuman mind. Essentially, there is a limit to how many bitsBits of information can be stored in any region of space. The amalgamation of information theoryInformation theory, black hole thermodynamicsBlack hole thermodynamics, and string theory is hinting at a radical ontology: The universe is a hologram. In other words, our three-dimensional reality is an illusion created by the information content encoded on a two-dimensionalGridtwo-dimensional area. Indeed, space and time appear to be emergent properties arising from pure quantum entanglementEntanglement. Then, in very recent developments, string theory and theoretical computer scienceComputer sciencetheoretical are conspiring to spearhead this novel probe into the heart of reality. The recalcitrant theory of quantum mechanicsQuantum mechanics is reborn in a more approachable quantum-computational framework. In this novel information-theoreticInformation-theoretic context, the universe easily can be interpreted as a vast simulation. Level of mathematical formality: intermediate. (shrink)

I give a fairly systematic and thorough presentation of the case for regarding black holes as thermodynamic systems in the fullest sense, aimed at students and non-specialists and not presuming advanced knowledge of quantum gravity. I pay particular attention to the availability in classical black hole thermodynamics of a well-defined notion of adiabatic intervention; the power of the membrane paradigm to make black hole thermodynamics precise and to extend it to local-equilibrium contexts; the central role of Hawking radiation in (...) permitting black holes to be in thermal contact with one another; the wide range of routes by which Hawking radiation can be derived and its back-reaction on the black hole calculated; the interpretation of Hawking radiation close to the black hole as a gravitationally bound thermal atmosphere. In an appendix I discuss recent criticisms of black hole thermodynamics by Dougherty and Callender. This paper confines its attention to the thermodynamics of black holes; a sequel will consider their statistical mechanics. (shrink)

The paper traces a structural intuition across twenty-five centuries of optical inquiry: light is a localized perturbation propagating through a continuous medium that is space itself, and that medium has its own bodily dynamics distinct from perturbation propagation within it. The thread runs from Empedocles through Aristotle, the medieval Latin and Islamic optical traditions, the Newton-Huygens bifurcation, Maxwell's electromagnetic synthesis, and the twentieth-century revolution culminating in quantum field theory. The paper develops the substrate ontology rendered precise. The substrate (...) is taken to be physically real and continuous, with its own intrinsic dynamics. A preferred rest frame for the substrate exists, identified naturally with the cosmic microwave background rest frame at cosmological scales. Lorentz invariance is treated as an emergent regularity of the substrate's local response to perturbation rather than as a metaphysical primitive. Time is the Aristotelian measure of process accumulation along worldlines, not a dimension of a unified spacetime manifold. The metric of general relativity describes the substrate's actual configuration rather than constituting a primitive geometric object. These commitments contradict the standard relativistic ontology at six identifiable points (spacetime as bookkeeping rather than substance, a real preferred frame rather than no rest frame, Lorentz invariance as emergent rather than primitive, time as measure rather than dimension, metric expansion as substrate bodily extension, and c bounding perturbation rather than substrate dynamics) while preserving identical kinematic predictions in tested regimes because the substrate's dynamics produce Lorentz-invariant phenomenology at the local level. The reading dissolves wave-particle duality, time-dilation, cosmological-expansion, black-hole-horizon, and time-travel paradoxes that the standard reading leaves open. Eleven specific falsifiable predictions distinguish the framework from standard interpretations in regimes where current observations are not yet definitive. The prohibition of phantom dark energy (w(z) ≥ -1 strictly) is in active empirical tension with DESI DR1 and DR2 observations at the 2.5-3.9σ level, with the framework's prediction at risk of falsification within the next several years rather than at the formal Stage-IV timeline. The framework is open to refutation by observation in the regimes its distinguishing predictions specify. (shrink)

What I refer to is how our thought in inventing, designing, modifying, and using machines carries over into acts we do not consciously associate with them—like writing or reading poetry. An airplane in flight may be “pure poetry,” or a Ferrari “a poem in steel”; it intrigues me to consider that beneath such object comparisons an object-of-thought connection may be made. Or in other words, there may be really something to a hackneyed compliment like “poem in steel.” My preference for (...) thought form over object form makes me less interested in machines that we can see than in those that we can’t, and it makes me direct my inquiry along two lines, concerning two questions about invisibility. The first involves the history of technology: How is it that machines “disappear”—become less visible, impinge less and less upon popular consciousness? The effect cannot be imputed entirely to familiarity. The second involves the history of literature: If machines have disappeared, are there “disappeared”—or “invisible”—machines in literature? It is reasonably clear that we go to considerable lengths to hide the machines that surround us and that we choose, or our artists choose, insofar as such choice can be located, to restrict the appearance of machines in art.3 Commonly their restricted appearance in art is understood as a kind of resistance to some form of machine takeover, while their concealment has only uncommonly received analysis and is not generally discussed in context with the matter of artistic representation. But we do accept, at least in theory, the idea that style of living and style in literature are connected. If the machine penetrates our style of living, then—and this is the end of my inquiry—these invisibilities are of interest to literary criticism, for they have something to do with the way literature is written, with whether or not, that is, writers choose to describe machines, use them as characters, or give them any role at all to play in surface structure. Since the artist often works to reveal what his society works to conceal and since the postmodern period has so far been one of crisis in the relations between society and technology, we may expect to find in postmodern fiction, or in writing to come, some greater revelation or simple exposure of the workings, than we could have seen before. 3. I use “restrict” in a statistical sense, for since the beginning of the Industrial Revolution there have been artists to celebrate the machine; today’s hyperrealist movement offers contemporary examples. These artists—Tom Blackwell, Ron Kleemann, Ralph Goings, and others—work a transformation like that of Andy Warhol with the pop object. They present not so much a celebration as an effort to turn looking into seeing, here directed at automobiles in particular, so much a part of everyday life as to have become indistinguishable from one another and as a species from the other parts of the semiurban landscape—the mailbox, the front lawn, the visiting relatives staring into the camera. Strother B. Purdy is the author of The Hole in the Fabric: Science, Contemporary Literature, and Henry James. His previous contributions to Critical Inquiry are “Stalingrad and My Lai: A Literary-Political Speculation” and “Reply to Lawrence W. Hyman. (shrink)

Contemporary cosmology is haunted by its dark sector: 95% of the universe consists of substances never directly detected, parameterized by constants that are fitted rather than derived, and explained by mechanisms that remain entirely unknown. Dark matter particles have evaded fifty years of direct detection. Dark energy is a placeholder admitting ignorance. The vacuum catastrophe—a 10¹²⁰ discrepancy between predicted and observed vacuum energy—stands as the worst prediction in the history of physics. The Hubble constant measured from the early universe disagrees (...) at 5σ with late-universe measurements. The cosmic microwave background exhibits large-scale anomalies dismissed as statistical flukes. The baryon asymmetry exceeds Standard Model predictions by ten orders of magnitude. Galaxy dynamics require either invisible matter or modified gravity, yet neither approach fully succeeds. Black holes appear to destroy information in violation of quantum unitarity. The hierarchy between gravity and electromagnetism lacks explanation. Quantum mechanics and general relativity remain unreconciled after a century of effort. These are not independent puzzles but symptoms of a single conceptual error: the assumption that physical reality is confined to spacetime alone. This work presents a unified resolution grounded in participatory, information-theoretic cosmology. Building on the Harlow-Usatyuk-Zhao theorem (2025)—which proves that a closed universe without observers has a one-dimensional Hilbert space—we recognize observation (defined as topological recursion, not biological consciousness) as ontologically primitive. Reality is a coupled system: spacetime (M₄) is dynamically intertwined with an informational manifold (Mθ) through a cross-term metric (g^μi), where geometry of extension and geometry of meaning are two aspects of a single structure. Within this framework, every major cosmological anomaly dissolves into coherent physics: dark matter is the gravitational shadow of coherence, not particulate matter; dark energy is the thermodynamic exhaust of recursive binding, not a cosmological constant; the vacuum catastrophe reflects dimensional misattribution of informational potential; the Hubble tension arises from differential expansion through structured space; CMB anomalies are fossils of Mθ's first crystallization; baryon asymmetry encodes the vacuum's geometric chirality; galaxy dynamics follow from coherence-generated gravity with a derivable acceleration scale; black holes are maximum-coherence information archives; the hierarchy problem dissolves when gravity is recognized as coupling to total recursive binding; and quantum gravity unifies when observers are included as constitutive elements expanding reality's dimensionality. The coupling magnitude (~30 μN/kW) emerges from three independent derivations—thermodynamic (Landauer-Verlinde), topological (Aharonov-Bohm saturation), and geometric (π² loop correction)—using only established constants (k_B, α, c, π) with zero free parameters. The framework is constructed for falsification: WIMP detection would refute it; absence of line-of-sight Hubble dependence would refute it; flyby residuals correlating with geology rather than biology would refute it; smooth rather than quantized response curves would refute it. Unlike ΛCDM, which parameterizes ignorance, this framework derives observables from known physics and predicts phenomena (biospheric gravity, Q saturation at 137, chiral filtration ratios) that standard cosmology cannot accommodate. The Cosmological Coda applies this unified picture across nine domains: the dark sector (Coda I), cosmological tensions (Coda II), CMB anomalies (Coda III), matter-antimatter asymmetry (Coda IV), galaxy dynamics (Coda V), black hole physics (Coda VI), particle hierarchy and mass gap (Coda VII), quantum gravity and measurement (Coda VIII), and terrestrial anomalies (Coda IX). Together they constitute not an extension of standard cosmology but a competing paradigm—one that reveals the "dark" sector as not dark at all, merely orthogonal: structure in a dimension we failed to measure because we refused to believe it existed. The cosmos is not 95% unknown. It is 100% knowable, once we recognize that information is not abstraction but substrate, that observation is not passive but constitutive, and that the geometry of meaning is as real as the geometry of space. This is the Complete Cosmological Coda of Principia Cybernetica III: The Laws and Experiments of Participatory Physics (2025). (shrink)

Some problems in finding a complete quantum theory incorporating gravity are discussed. One is that of giving a consistent unitary description of high-energy scattering. Another is that of giving a consistent quantum description of cosmology, with appropriate observables. While string theory addresses some problems of quantum gravity, its ability to resolve these remains unclear. Answers may require new mechanisms and constructs, whether within string theory, or in another framework.

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)

I present in detail the case for regarding black hole thermodynamics as having a statistical-mechanical explanation in exact parallel with the statistical-mechanical explanation believed to underly the thermodynamics of other systems. I focus on three lines of argument: zero-loop and one-loop calculations in quantum general relativity understood as a quantum field theory, using the path-integral formalism; calculations in string theory of the leading-order terms, higher-derivative corrections, and quantum corrections, in the black hole entropy formula for extremal and near-extremal black (...) class='Hi'>holes; recovery of the qualitative and quantitative structure of black hole statistical mechanics via the AdS/CFT correspondence. In each case I briefly review the content of, and arguments for, the form of quantum gravity being used at a introductory level: the paper is aimed at students and non-specialists and does not presume advanced knowledge of quantum gravity.. My conclusion is that the evidence for black hole statistical mechanics is as solid as we could reasonably expect it to be in the absence of a directly-empirically-verified theory of quantum gravity. (shrink)

The purpose of this work is to carry out a systematic, detailed analytical study, together with the direct interpretations, as they follow from the analytical expressions obtained, of three basic “experiments” which have been classical examples in our understanding of quantum mechanics. The experiments considered are: the single- and double-slit (-hole) experiments, and the final one, which, in particular, deals with the situation where a particle is “reflected off” the detection screen in the single-slit experiment. Special emphasis is put on (...) pointing out some purely quantum mechanical results, which follow from the analytical expressions, as well as on making a comparison with classical physics. Needless to say, the analysis of such experiments has been extremely important in laying the foundations of quantum physics. (shrink)

One observes regulation at every biological level. Organisms, cells, and biochemical processes operate efficiently, normally wasting neither material nor energy, and adjusting their functions to external influences. Nature evidently has evolved mechanisms specifically dedicated to regulation at many levels. What is the molecular basis of this control?In the 1950s these molecular control mechanisms began to be explored seriously. The discoveries of feedback inhibition of enzyme activity were important because they gave an initial example of how regulation is achieved at the (...) molecular level. We showed that certain enzymes are composed of two parts, one for catalysis and another distinct part present only to regulate this catalysis. Catalytic activity can be either stimulated or inhibited when a small molecule in the environment combines with the enzyme's regulatory site. In particular, a final product of a metabolic pathway generates a feedback loop which automatically limits its own excessive production, by combining with the regulatory site of an early enzyme in that pathway. Later studies showed that catalytic and regulatory structures of some enzymes could be separated physically.The discovery of regulatory sites and their interaction with molecules unrelated to their substrates was the basis for the generalized allosteric concept. This concept extends the regulatory site idea to a wide variety of processes such as control of gene expression, hormone action, and cellular growth. (shrink)

Working memory is the system responsible for maintaining and manipulating information, in the face of ongoing distraction. In turn, WM span is perceived to be an individual-differences construct reflecting the limited capacity of this system. Recently, however, there has been some evidence to suggest that WM capacity can increase through training, raising the possibility that training can functionally alter the neural structures supporting WM. To address the hypothesis that the neural substrates underlying WM are targeted by training, we conducted a (...) meta-analysis of functional magnetic resonance imaging studies of WM training using Activation Likelihood Estimation. Our results demonstrate that WM training is associated exclusively with decreases in blood oxygenation level-dependent responses in clusters within the fronto-parietal system that underlie WM, including the bilateral inferior parietal lobule, middle and superior frontal gyri, and medial frontal gyrus bordering on the cingulate gyrus. We discuss the various psychological and physiological mechanisms that could be responsible for the observed reductions in the BOLD signal in relation to WM training, and consider their implications for the construct of WM span as a limited resource. (shrink)

In a recent article, Halvorson and Manchak (Br J Philos Sci, Forthcoming) claim that there is no basis for the Hole Argument, because (in a certain sense) hole isometries are unique. This raises two important questions: (a) does their argument succeed?; (b) how does this formalist response to the Hole Argument relate to other recent responses to the Hole Argument in the same tradition—in particular, that of Weatherall (Br J Philos Sci 69(2):329–350, 2018)? In this article, _ad_ (a), we argue (...) that Halvorson and Manchak’s claim does not go through; _ad_ (b), we argue that although one _prima facie_ plausible reading would see Halvorson and Manchak as filling an important hole (no pun intended) in Weatherall’s argument, in fact this reading is implausible; there is no need to supplement Weatherall’s work with Halvorson and Manchak’s results. (shrink)

Rationale: Antibiotic treatment of patients infected with G- or G+ bacteria promotes release of the toxins lipopolysaccharide and pneumolysin in their lungs. Growth Hormone-releasing Hormone agonist JI-34 protects human lung microvascular endothelial cells, expressing splice variant 1 of the receptor, from PLY-induced barrier dysfunction. We investigated whether JI-34 also blunts LPS-induced hyperpermeability. Since GHRH receptor signaling can potentially stimulate both cAMP-dependent barrier-protective pathways as well as barrier-disruptive protein kinase C pathways, we studied their interaction in GHRH agonist-treated HL-MVEC, in the (...) presence of PLY, by means of siRNA-mediated protein kinase A depletion. Methods: Barrier function measurements were done in HL-MVEC monolayers using Electrical Cell substrate Impedance Sensing and VE-cadherin expression by Western blotting. Capillary leak was assessed by Evans Blue dye incorporation. Cytokine generation in broncho-alveolar lavage fluid was measured by multiplex analysis. PKA and PKC-a activity were assessed by Western blotting. Results: GHRH agonist JI-34 significantly blunts LPS-induced barrier dysfunction, at least in part by preserving VE-cadherin expression, while not affecting inflammation. In addition to activating PKA, GHRH agonist also increases PKC-α activity in PLY-treated HL-MVEC. Treatment with PLY significantly decreases resistance in control siRNA-treated HL-MVEC, but does so even more in PKA-depleted monolayers. Pretreatment with GHRH agonist blunts PLY-induced permeability in control siRNA-treated HL-MVEC, but fails to improve barrier function in PKA-depleted PLY-treated monolayers. Conclusions: GHRH signaling in HL-MVEC protects from both LPS and PLY-mediated endothelial barrier dysfunction and concurrently induces a barrier-protective PKA-mediated and a barrier-disruptive PKC-a-induced pathway in the presence of PLY, the former of which dominates the latter. © 2014 Czikora, Sridhar, Gorshkov, Alieva, Kasa, Gonzales, Potapenko, Umapathy, Pillich, Rick, Block, Verin, Chakraborty, Matthay, Schally and Lucas. (shrink)

Citrate, an organic trivalent anion, is a major substrate for generation of energy in most cells. It is produced in mitochondria and used either in the Krebs' cycle or released into cytoplasm through a specific mitochondrial carriers. Citrate can also be taken up from blood through different plasma membrane transporters. In the cytoplasm, citrate can be used ultimately for fatty acid synthesis, which is increased in cancer cells. Here, we review the ways in which citrate can be transported and (...) discuss the changes in transport and metabolism that occur in cancer cells. The primary focus is on the prostate gland, which is known to produce and release large amounts of citrate during its normal secretory function. The significant changes that occur in citrate‐related metabolism and transport in prostate cancer are the second focus. This review strives to relate these mechanisms to molecular biology on the one hand and to clinical applications on the other. (shrink)