We give a partial answer to an important open problem in descriptive set theory, the Decomposability Conjecture for Borel functions on an analytic subset of a Polish space to a separable metrizable space. Our techniques employ deep results from effective descriptive set theory and recursion theory. In fact it is essential to extend several prominent results in recursion theory (e.g. the Shore-Slaman Join Theorem) to the setting of Polish spaces. As a by-product we give both positive and negative results on (...) the Martin Conjecture on the degree preserving Borel functions between Polish spaces. Additionally we prove results about the transfinite version as well as the computable version of the Decomposability Conjecture. (shrink)

Let X be a separable Banach space and Q be a coanalytic subset of . We prove that the set of sequences in X which are weakly convergent to some eX and is a coanalytic subset of . The proof applies methods of effective descriptive set theory to Banach space theory. Using Silver’s Theorem [J. Silver, Every analytic set is Ramsey, J. Symbolic Logic 35 60–64], this result leads to the following dichotomy theorem: if X is a Banach space, is (...) a regular method of summability and is a bounded sequence in X, then there exists a subsequence iL such that either there exists eX such that every subsequence iH of iL is weakly summable w.r.t. to e and QiH,e); or for every subsequence iH of iL and every eX with QiH,e)the sequence iH is not weakly summable to e w.r.t. . This is a version for weak convergence of an Erdös–Magidor result, see [P. Erdös, M. Magidor, A note on Regular Methods of Summability, Proc. Amer. Math. Soc. 59 232–234]. Both theorems obtain some considerable generalizations. (shrink)

We prove a recursion theoretic characterization of the Topological Vaught Conjecture in the Zermelo‐Fraenkel set theory by using tools from effective descriptive set theory and by revisiting the result of Miller that orbits in Polish G‐spaces are Borel sets.

Selectionist evolutionary theory has often been faulted for not making novel predictions that are surprising, risky, and correct. I argue that it in fact exhibits the theoretical virtue of predictive capacity in addition to two other virtues: explanatory unification and model fitting. Two case studies show the predictive capacity of selectionist evolutionary theory: parallel evolutionary change in E. coli, and the origin of eukaryotic cells through endosymbiosis.

A map is not its territory. Taking a map too seriously may lead to pernicious reification: map and world are conflated. As one family of cases of such reification, I focus on maps exuding the omphalos syndrome, whereby a centred location on the map is taken to be the world navel of, for instance, an empire. I build on themes from my book _When Maps Become the World_, in which I analogize scientific theories to maps, and develop the tools of (...) assumption archaeology and integration platforms. Here I argue that excavating assumptions helps fill cartographic silences, showing the limitations of perspectives often at war. Furthermore, integrating perspectives permits resisting imperial central or master images. A worthwhile future project would be a repository of world-navel maps, critically annotated with cultural context and imperial information. Mutual understanding may result from such an integration platform, perhaps implemented online or in a museum. (shrink)

Evo-Devo exhibits a plurality of scientific “cultures” of practice and theory. When are the cultures acting—individually or collectively—in ways that actually move research forward, empirically, theoretically, and ethically? When do they become imperialistic, in the sense of excluding and subordinating other cultures? This chapter identifies six cultures – three /styles/ (mathematical modeling, mechanism, and history) and three /paradigms/ (adaptationism, structuralism, and cladism). The key assumptions standing behind, under, or within each of these cultures are explored. Characterizing the internal structure of (...) the cultures is necessary for understanding how they collaborate or compete, and how they are fragmented or integrated, in the rich interdisciplinary /trading zone/ (Galison 1997) of Evo-Devo. Evo-Devo is an important example of how science can progress through a radical plurality of perspectives and cultures. (shrink)

This article investigates young second language learners’ participation in explanatory discourse during peer play in preschools. Twenty-seven 5-year-old Turkish-speaking children in Norwegian preschools were studied in peer play. Characteristics of conversational moves and of various explanatory types, as well as how such types were related to children’s academic language skills in Turkish and Norwegian were examined. Children, both native and non-native speakers of Norwegian, mostly produced explanations spontaneously, while requests for explanations occurred only occasionally. Second language learners who attended play (...) groups with much explanatory peer talk had higher academic language skills. In particular, we discuss whether second language learners with more Principle-based Explanations had higher academic language skills in Norwegian. The contribution of peer play explanatory talk to second language learners’ academically mediated language skills is discussed. (shrink)

The essays in Invisibility in Visual and Material Culture contribute pioneering and revelatory insights into the phenomenon of invisibility, forging new and multi-disciplinary approaches at the intersection of aesthetics, technology, representation and politics. Importantly, they acknowledge the complex interaction between invisibility and its opposite, visibility, arguing that the one cannot be fully grasped without the other. Considering these entanglements across different media forms, the chapters reveal that the invisible affects many cultural domains, from digital communication and operative images to the (...) activism of social movements, as well as to identity, race, gender and class issues. Whether the subject is comic books, photographic provocations, biometric and brainwave sensing technologies, letters, or a cinematic diary, the analyses in this book engage critically and theoretically with the topic of invisibility and thus represent the first scholarly study to identify its importance for the field of visual culture. (shrink)

Arne Grøn’s reading of Søren Kierkegaard’s authorship revolves around existential challenges of human identity. The 35 essays that constitute this book are written over three decades and are characterized by combining careful attention to the augmentative detail of Kierkegaard’s text with a constant focus on issues in contemporary philosophy. Contrary to many approaches to Kierkegaard’s authorship, Grøn does not read Kierkegaard in opposition to Hegel. The work of the Danish thinker is read as a critical development of Hegelian phenomenology with (...) particular attention to existential aspects of human experience. Anxiety and despair are the primary existential phenomena that Kierkegaard examines throughout his authorship, and Grøn uses these negative phenomena to argue for the basically ethical aim of Kierkegaard’s work. In Grøn’s reading, Kierkegaard conceives human selfhood not merely as relational, but also a process of becoming the self that one is through the otherness of self-experience, that is, the body, the world, other people, and God. This book should be of interest to philosophers, theologians, literary studies scholars, and anyone with an interest not only in Kierkegaard, but also in human identity. (shrink)

A rotating disk with angular acceleration is given a relativistic description as observed from the rotating rest frameR of the disk. It is shown how a non-Euclidean intrinsic spatial geometry develops inR, as the disk gets an angular velocity. The explanation of this as given by anR-observer is discussed. A recent description of the geometry inR presented by Grünbaum and Janis is criticized. The motion of light as described by use of coordinate clocks inR is discussed in connection with some (...) recent work by R. C. Jennison and coworkers. The significance of the difference between directed signals and circular waves when clocks inR are to be synchronized by means of light emitted from the axis inR is made clear. (shrink)

Kierkegaard y Hegel son puntos de referencia en la Filosofía moderna. El artículo se ocupa de cómo debe ser entendida la ética si partimos de la noción de la relación entre la relación consigo mismo y el otro, al reinterpretar a Hegel y a Kierkegaard. En la primera parte se discute la cuestión de la dimensión normativa del reconocimiento, por mediante la interpretación de la teoría del reconocimiento hegeliana en Fenomenología del espíritu, capítulo IV A. En la segunda parte, se (...) interpreta la "segunda" ética de Kierkegaard en trabajos sobre el amor como una ética de la visión. Se plantea que el reconocimiento, como medio para ver al otro, es una comunicación en la cual está en juego la relación entre la relación consigo-mismo y el otro. (shrink)

It is shown how a consistent kinematic resolution of Ehrenfest's paradox may be given in accordance with the special theory of relativity. Some statements by T. E. Phipps, Jr., connected with these matters, are commented upon. Problems connected with the relation between stress and strain are solved by a manifestly covariant formulation of Hooke's law.

If the title of this article resounds with the polemical palavering of literary theory in the 1940s, I have to submit that the allusion is not entirely accidental. It is not my intention here, however, to resuscitate the arguments of W. K. Wimsatt Jr and Monroe C. Beardsley, but rather to evoke a sense of parallelism between their issues and those at stake here. A crucial objective which informed Wimsatt's and Beardsley's project was to buttress the significance and irreducibility of (...) the literary text in the face of monopolistic authorial and receptional meaning-making. [3] The scholarly environment that was American New Criticism tended to consider intentionalism and emotionalism as threats to the epistemological prominence and integrity of the text, which was all too readily lost in a plenitude of contexts whose relevance for the literary work was not always impressively transparent. Similarly, within the domain of film studies, it has perhaps become increasingly unclear whether the real object of study is the film text itself, or rather a concatenation of different disciplinary discourses hailing from departments of psychology, sociology, and biology (to name a few). The colonization of cinema studies is not a novel development; as a process its apogee was in the 1970s. (shrink)

This chapter examines Soren Kierkegaard's views about the concept of time and history. It suggests that while time and history do not figure prominently in the works of Kierkegaard, the implications of his key concepts can only be understood through the questions of time and history, particularly his ideas about selfhood, existence, and the ethical. The chapter also discusses the different notions of time and history, and considers how time and history come into play in the works of Kierkegaard.

In a recent article in this journal, Kingsley has tried to show that the postulates of special relativity contradict each other. Here we show that the arguments of Kingsley are invalid because of an erroneous appeal to symmetry in a non-symmetric situation. The consistency of the postulates of special relativity and the relativistic kinematics deduced from them is restated.

The question is discussed whether the description of the gravitational Doppler effect as a simple energy effect is consistent with its general-relativistic description as a metric-time effect. The difference between a local description and a global one is stressed. In the local description one is permitted to ignore metric effects. The global description yields a position-dependent rate of proper time in a gravitational field, and the energy, or the frequency, of a “freely falling” photon is described as a constant of (...) motion. An experiment of nonlocal character measuring, simultaneously, the gravitational Doppler effect and the position-dependent rate of proper time may be performed by the use of a geostationary satellite. A simple general-relativistic treatment of the satellite experiment is obtained by transforming the Schwarzschild metric to a rotating frame, and describing the motion of free particles and the rates of standard clocks in the resulting metric. (shrink)

Using the Weyl-type canonical coordinates, an integration of Einstein's field equations in the cylindrosymmetric case considered by Kurşunoğlu is reexamined. It is made clear that the resulting metric is not describing the spacetime in a rotating frame, but in astatic cylindrical elastic medium. The conclusion of Kurşunoğlu that “for an observer on a rotating disk there is no way of escape from a curved spacetime” is therefore not valid. The metric in an empty rotating frame is found as a solution (...) of Einstein's field equations, and is not orthogonal. It is shown that the corresponding orthogonal solution represents spacetime in an inertial frame expressed in cylindrical coordinates. Introducing a noncoordinate basis, the metric in a rotating frame is given the static form of Kurşunoğlu's solution. The essential role played by the nonvanishing structure coefficients in this case is made clear. (shrink)

"This book originates from a conference ... which took place at the Danish National Research Foundation's Center for Subjectivity Research, University of Copenhagen, on December 4-5, 2008... The articles collected ... are not proceedings but a selection of re-written texts from the conference including additional texts by authors invited to contribute to the book"--Page V.

Einstein's gravitational field equations in empty space outside a massive plane with infinite extension give a class of solutions describing a field with flat spacetime giving neutral, freely moving particles an acceleration. This points to the necessity of defining the concept “gravitational field” not simply by the nonvanishing of the Riemann curvature tensor, but by the nonvanishing of certain elements of the Christoffel symbols, called the physical elements, or the nonvanishing of the Riemann curvature tensor. The tidal component of a (...) gravitational field is associated with a nonvanishing Riemann tensor, while the nontidal components are associated with nonvanishing physical elements of the Christoffel symbols. Spacetime in a nontidal gravitational field is flat. Such a field may be separated into a homogeneous and a rotational component. In order to exhibit the physical significance of these components in relation to their transformation properties, coordinate transformations inside a given reference frame are discussed. The mentioned solutions of Einstein's field equations lead to a metric identical to that obtained as a result of a transformation from an inertial frame to a uniformly accelerated frame. The validity of the strong principle of equivalence in extended regions for nontidal gravitational fields is made clear. An exact calculation of the weight of an extended body in a uniform gravitational field, from a global point of view, gives the result that its weight is independent of the position of the scale on the body. (shrink)

Kierkegaard y Hegel son puntos de referencia en la Filosofía moderna. El artículo se ocupa de cómo debe ser entendida la ética si partimos de la noción de la relación entre la relación consigo mismo y el otro, al reinterpretar a Hegel y a Kierkegaard. En la primera parte se discute la cuestión de la dimensión normativa del reconocimiento, por mediante la interpretación de la teoría del reconocimiento hegeliana en Fenomenología del espíritu, capítulo IV A. En la segunda parte, se (...) interpreta la "segunda" ética de Kierkegaard en trabajos sobre el amor como una ética de la visión. Se plantea que el reconocimiento, como medio para ver al otro, es una comunicación en la cual está en juego la relación entre la relación consigo-mismo y el otro. (shrink)