In honour of Detlef Dürr, we report on a mathematical rigorous computation of the electric vacuum polarisation current and extract the well-known expression for the second order perturbation. Intermediate steps in the presented calculation demonstrate, to the knowledge of the authors for the first time, mathematical rigorous versions of the combined dimensional and Pauli-Villars regularisation schemes. These are employed as computational tools to infer convenient integral representations during the computation. The said second order expression is determined up to a remaining (...) degree of freedom of a real number–without ill-defined terms from start to end. (shrink)

We show that the Bohmian approach in terms of persisting particles that move on continuous trajectories following a deterministic law can be literally applied to quantum field theory. By means of the Dirac sea model—exemplified in the electron sector of the standard model neglecting radiation—we explain how starting from persisting particles, one is led to standard QFT employing creation and annihilation operators when tracking the dynamics with respect to a reference state, the so-called vacuum. Since on the level of wave (...) functions, both formalisms are mathematically equivalent, this proposal provides for an ontology of QFT that includes a dynamics of individual processes, solves the measurement problem, and explains the appearance of creation and annihilation events. 1Bohmian Mechanics from Quantum Mechanics to Quantum Field Theory2The Dirac Sea Model3Equilibrium States and the Vacuum4Excitations of the Vacuum and the Fock Space Formalism5The Appearance of Particle Creations and Annihilations6The Merits of the Bohmian Approach. (shrink)

We show that the Bohmian approach in terms of persisting particles that move on continuous trajectories following a deterministic law can be literally applied to QFT. By means of the Dirac sea model – exemplified in the electron sector of the standard model neglecting radiation – we explain how starting from persisting particles, one is led to standard QFT employing creation and annihilation operators when tracking the dynamics with respect to a reference state, the so-called vacuum. Since on the level (...) of wave functions, both formalisms are mathematically equivalent, this proposal provides for an ontology of QFT that includes a dynamics of individual processes, solves the measurement problem and explains the appearance of creation and annihilation events. (shrink)

This book seeks to work out which commitments are minimally sufficient to obtain an ontology of the natural world that matches all of today’s well-established physical theories. We propose an ontology of the natural world that is defined only by two axioms: (1) There are distance relations that individuate simple objects, namely matter points. (2) The matter points are permanent, with the distances between them changing. Everything else comes in as a means to represent the change in the distance relations (...) in a manner that is both as simple and as informative as possible. The book works this minimalist ontology out in philosophical as well as mathematical terms and shows how one can understand classical mechanics, quantum field theory and relativistic physics on the basis of this ontology. Along the way, we seek to achieve four subsidiary aims: (a) to make a case for a holistic individuation of the basic objects (ontic structural realism); (b) to work out a new version of Humeanism, dubbed Super-Humeanism, that does without natural properties; (c) to set out an ontology of quantum physics that is an alternative to quantum state realism and that avoids any ontological dualism of particles and fields; (d) to vindicate a relationalist ontology based on point objects also in the domain of relativistic physics. (shrink)

This paper elaborates on relationalism about space and time as motivated by a minimalist ontology of the physical world: there are only matter points that are individuated by the distance relations among them, with these relations changing. We assess two strategies to combine this ontology with physics, using classical mechanics as example: the Humean strategy adopts the standard, non-relationalist physical theories as they stand and interprets their formal apparatus as the means of bookkeeping of the change of the distance relations (...) instead of committing us to additional elements of the ontology. The alternative theory strategy seeks to combine the relationalist ontology with a relationalist physical theory that reproduces the predictions of the standard theory in the domain where these are empirically tested. We show that, as things stand, this strategy cannot be accomplished without compromising a minimalist relationalist ontology. (shrink)

The paper sets out and defends against criticism the claims argued for in the book A minimalist ontology of the natural world.

We set out a fundamental ontology of atomism in terms of matter points. While being most parsimonious, this ontology is able to match both classical and quantum mechanics, and it remains a viable option for any future theory of cosmology that goes beyond current quantum physics. The matter points are structurally individuated: all there is to them are the spatial relations in which they stand; neither a commitment to intrinsic properties nor to an absolute space is required. The spatial relations (...) change. All that is needed to capture change is a dynamical structure, namely dynamical relations as expressed in terms of the dynamical parameters of a physical theory. (shrink)

The Many-Interacting-Worlds (MIW) approach to a quantum theory without wave functions proposed in [8] leads naturally to numerical integrators of the Schrödinger equation on comoving grids. As yet, little is known about concrete MIW models for more than one spatial dimension and/or more than one particle. In honour of Detlef Dürr, we report on a further development of the MIW approach to treat arbitrary degrees of freedom and provide a numerical proof of concept for ground states in 2d. The latter (...) is part of a systematic numerical study [22] that includes also 1d ground and excited states. With this step towards the treatment of higher degrees of freedom we hope to stimulate their further study. (shrink)

By means of the examples of classical and Bohmian quantum mechanics, we illustrate the well-known ideas of Boltzmann as to how one gets from laws defined for the universe as a whole to dynamical relations describing the evolution of subsystems. We explain how probabilities enter into this process, what quantum and classical probabilities have in common and where exactly their difference lies.

Although laughter plays an essential part in emotional vocal communication, little is known about the acoustical correlates that encode different emotional dimensions. In this study we examined the acoustical structure of laughter sounds differing along four emotional dimensions: arousal, dominance, sender's valence, and receiver-directed valence. Correlation of 43 acoustic parameters with individual emotional dimensions revealed that each emotional dimension was associated with a number of vocal cues. Common patterns of cues were found with emotional expression in speech, supporting the hypothesis (...) of a common underlying mechanism for the vocal expression of emotions. (shrink)

Michael Esfeld & Dirk-André Deckert, A Minimalist Ontology of the Natural World. New York/Abingdon: Routledge, 2018.

‘Know-that’, like so many natural language expressions, exhibits patterns of use that provide evidence for its context-sensitivity. A popular family of views – call it prag- matic invariantism – attempts to explain the shifty patterns by appeal to a pragmatic thesis: while the semantic meaning of ‘know-that’ is stable across all contexts of use, sentences of the form ‘S knows [doesn’t know] that p’ can be used to communicate a pragmatic content that depends on the context of use. In this (...) paper, the author argues that pragmatic invariantism makes inaccurate predictions for a wide range of well- known use data and is committed to attributing systematic pragmatic error to ordinary speakers. But pragmatic error is unprecedented, and it is doubtful that speakers are systematically wrong about what they intend to communicate. (shrink)

We show that it is impossible in quantum mechanics to describe two separated physical systems. This is due to the mathematical structure of quantum mechanics. It is possible to give a description of two separated systems in a theory which is a generalization of quantum mechanics and of classical mechanics, in the sense that this theory contains both theories as special cases. We identify the axioms of quantum mechanics that make it impossible to describe separated systems. One of these axioms (...) is equivalent to the superposition principle. We show how these findings throw a different light on the paradox of Einstein, Podolsky, and Rosen. (shrink)

In "Plato's Ghost" Jeremy Gray presented many connections between mathematical practices in the nineteenth century and the rise of mathematical platonism in the context of more general developments, which he refers to as modernism. In this paper, I take up this theme and present a condensed discussion of some arguments put forward in favor of and against the view of mathematical platonism. In particular, I highlight some pressures that arose in the work of Frege, Cantor, and Gödel, which support adopting (...) a platonist position. The aim of this discussion is to provide an historically informed introduction to the philosophical position of mathematical platonism and to point at some of its mathematical and philosophical roots in the nineteenth century. (shrink)

We propose a characterization of mathematical experiments in terms of a setup, a process with an outcome, and an interpretation. Using a broad notion of process, this allows us to consider arithmetic calculations and geometric constructions as components of mathematical experiments. Moreover, we argue that mathematical experiments should be considered within a broader context of an experimental research project. Finally, we present a particular case study of the genesis of a geometric construction to illustrate the experimental use of hand drawings (...) and computers in mathematical practice. (shrink)

The works of the early Greek philosophers are not only a fundamental source for understanding archaic Greek culture and the whole of ancient philosophy, but also a perennially fresh resource that has stimulated Western thought until the present day. This nine-volume edition presents all the major fragments from the sixth to the fourth centuries BC.

There has recently been a wave of attempts to make sense of the role of de se thoughts in linguistic communication. A majority of the attempts assume a Perryan or a Lewisian view of de se thought. Views with these assumptions, I suggest, come in four varieties: uncentering (Egan 2007, Kölbel 2013, Moss 2012), recentering (Heim 2004, Weber 2012), multicentering (Kindermann 2014, Ninan 2010, Torre 2009), and no centering (Kaplan 1989, Perry 1979). I argue first that all four varieties of (...) centering are committed to what I call a shifting operation on the hearer's part. I argue second that, against common assumption, there is no real choice to make between the views. By showing that attempts to establish an advantage for some view over the others fail across the board, I make the case for neutralism regarding the varieties of centering – the claim that coverage of the empirical data is exactly the same for each view, and that the views are broadly equal in simplicity and elegance. (shrink)

In this paper we examine some of the astrological content in Proclus' exegesis of the 'nuptial number' in Republic 545d, ff. The downfall of the best city-state is said by Socrates to be due to the fact that the Guardians, for all their wisdom, make a mistake about the timing of the breeding of future rulers and this mistake is somehow due to perception. We argue that Proclus' Republic Commentary is best understood as supposing that the Guardians are highly capable (...) astrologers who can -- up until one fateful day -- reliably hit the astrological trifecta: they combine conception astrology with natal and katarchic astrology. The marriage festivals are timed so that future Guardians are conceived under the right stars, with pregnancies of the right duration, and are born under the right stars, with guardian daemons whose names and natures are known through an astrologically-oriented theurgic practice. All this (and more) Proclus took to be hinted at through Socrates' opaque specification of the marriage number. (shrink)

Plato's Tim. 90b1-c6 describes a pathway to the soul's salvation via the study of the heavens. This paper poses three questions about this theme in Platonism: 1. The epistemological question: How is the paradigmatic function of the visible heavenly bodies to be reconciled with various Platonic misgivings about the faculty of perception? 2. The metaphysical question: How can »assimilation« to the motions of bodies in the realm of Becoming provide for the salvation of souls when souls are »higher«- a mid-point (...) between Being and Becoming? 3. The psychological question: What can it mean for an incorporeal soul to utilise the motions of a body for an ethical and cognitive paradigm? And provides an account of how Proclus and some of his fellow Neoplatonists answered these questions. (shrink)

Volume IV (which comprises two half-volumes) focuses on the life sciences, whose object of research is life itself, that which (necessarily) mediates between the physical and the psyche. Typical philosophical questions in this context include: What is “life” in the sense of the term relevant to the life sciences? How do we know that life has not “always existed” but must have arisen in the course of abiogenesis from inanimate nature? And how is it possible to know something about how (...) evolution has occurred? These are explored in the first half-volume. In its second half-volume, the book first deals with methodological and conceptual questions regarding the concrete natural history of mankind. Examples for pertinent questions in this context are: "What would be adequate criteria for singling out autapomorphic traits defining the genus "homo"?" and "Has the concept of "race" biological meaning and reality?" (Spoiler: The answer to the latter question is "no".) In the context of that question, a considerable part of the second half-volume deals with the history of "scientific" theories of race from the 17th century up until the 1990ies. In particular, Kant's theory of race and his racism (as well as his sexism) are discussed thoroughly. Pertinent questions are: "Did Kant invent the concept of race?", "Was Kant the founder of "scientific racism"?", "Did Kant invent and promote a concept of "racial purity"?" and "Did Kant endorse slave trade?". Furthermore, for anyone whose own philosophical positions rest on Kantian premises, the following questions will be of special importance: "Is Kant's racism implied by his transcendental philosophy?" and "Is Kant's racism implied by his ethics?" Regarding all these questions, the contributions of important authors like Eze, Bernasconi, Kleingeld and Mills are discussed and critically examined. Finally, the second half-volume closes with a thorough exploration of the methodological foundations of neuroscience and its limitations as a contribution to philosophy of mind (which as such will have its say in Volume VI). (shrink)

Dirk Paul Bogner widmet sich der Frage, welche Relevanz Kurt Lewins Feldtheorie im Bereich der pädagogischen Diagnostik haben könnte. Er untermauert die These, dass die Lewin’sche Feldtheorie eine völlig neue Sicht auf Lern-, Entwicklungs- und Erziehungsprozesse eröffnen würde, und legt dar, inwiefern die Einbeziehung der Dimension des Raumes die Analyse dieser erziehungswissenschaftlich relevanten Topoi verfeinern könnte. Er erörtert mittels hermeneutischer Textauslegung und vergleichender Dokumentenanalyse, warum Lewin keine erziehungswissenschaftliche Resonanz erzeugen konnte, obwohl in der Erziehungswissenschaft auch heute noch intensiv Begriffe, (...) die entweder direkt aus der Feldtheorie stammen oder aber von dieser konsequent definiert wurden, verwendet werden. (shrink)

To this day, there persists a widespread assumption that Adorno's references to Marx - and especially to Marx's critique of political economy - represent a relic from an early and short-lived stage of Adorno's theoretical development. On the basis of relevant and largely unpublished textual sources, this book refutes this thesis while showing that the centre of Adorno's critical theory of society is occupied by a critique not only of political economy, but of economy in general.

Gesprekken tussen filosoof en ecoloog Johan Braeckman en moraalfilosoof Dirk Verhofstadt over de evolutietheorie van Darwin, religie, irrationalieit, humanisme en atheïsme."--Publisher information.

In der synthetischen Biologie werden Methoden insbesondere der Molekularbiologie, der Ingenieurwissenschaften und der Informationstechnik miteinander verbunden. Ziel dieser Kooperation ist die Erzeugung von biologischen Konstrukten, die weder eindeutig der Kategorie eines naturlich gewachsenen Organismus noch der einer technisch geschaffenen Maschine zuzuordnen sind. Die synthetische Biologie wirft damit ethische und naturphilosophische Fragen auf und stellt zudem neue Anforderungen an die bisherigen rechtlichen Regelungen.

'Risquons-Tout' is an ambitious, thematic group exhibition that explores the potential of transgression and unpredictability. It examines how art challenges the homogenisation of thought in the now infamous echo chambers of our overcrowded info-sphere. 'Risquons-Tout' presents some of the most innovative and influential artists and authors from the Eurocore region, which extends between Amsterdam, Paris, Cologne, Düsseldorf and London, with Brussels at its centre. The title is borrowed from a place located on the Belgian-French border, a real yet liminal space (...) of transition, passage and informal exchanges, notably smuggling. The invited artists negotiate different dynamics of bridging, passing, translating and transgressing. In doing so they burst the safe bubbles generated by prediction algorithms, designed to avoid any risk, whether intellectual, financial, emotional or physical. The exhibition's geographic and political scope addresses today's global connectivity, trans-national circulation and diasporic movements. 'Risquons-Tout' will occupy the entire WIELS building and range out into neighbouring exhibition and performance spaces. It will present the works of 38 internationally recognised or emerging artists. The exhibition proposes a rich array of practices that defy easy categorisation. 'Risquons-Tout' will also include a performative section and an Open School that will serve as a laboratory for artists and scholars to draw upon questions of risk, unpredictability and borders through a range of alternative methods for the transmission of knowledge. Exhibition: WIELS, Brussels, Belgium (12.09.2020 - 10.01.2021). (shrink)

The thesis of mental fragmentation has recently attracted increased attention as a way of explaining facts about mind and language. This volume provides an accessible introduction and essays on foundations and applications of fragmentation.

This book offers a penetrating analysis of issues raised by the perennial question, 'Are We Special?' It brings together scholars from a variety of disciplines, from astronomy and palaeontology to philosophy and theology, to explore this question. Contributors cover a wide variety of issues, including what makes humans distinct from other animals, the possibilities of artificial life and artificial intelligence, the likelihood of life on other planets, and the role of religious behavior. A variety of religious and scientific perspectives are (...) brought to bear on these matters. As a whole, the book addresses whether the issue of human uniqueness is one to which sciences and religions necessarily offer differing responses. (shrink)