124,692 research outputs found
Categorical models for equivariant classifying spaces
Starting categorically, we give simple and precise models of equivariant
classifying spaces. We need these models for work in progress in equivariant
infinite loop space theory and equivariant algebraic K-theory, but the models
are of independent interest in equivariant bundle theory and especially
equivariant covering space theory.Comment: 29 pages. Revised version, to appear in AGT. Considerable changes of
notation and organization and other changes aimed at making the paper more
user friendl
Diagram spaces, diagram spectra, and spectra of units
This article compares the infinite loop spaces associated to symmetric
spectra, orthogonal spectra, and EKMM S-modules. Each of these categories of
structured spectra has a corresponding category of structured spaces that
receives the infinite loop space functor \Omega^\infty. We prove that these
models for spaces are Quillen equivalent and that the infinite loop space
functors \Omega^\infty agree. This comparison is then used to show that two
different constructions of the spectrum of units gl_1 R of a commutative ring
spectrum R agree.Comment: 62 pages. The definition of the functor \mathbb{Q} is changed.
Sections 8, 9, 17 and 18 contain revisions and/or new materia
Continuous functors as a model for the equivariant stable homotopy category
In this paper, we investigate the properties of the category of equivariant
diagram spectra indexed on the category W_G of based G-spaces homeomorphic to
finite G-CW-complexes for a compact Lie group G. Using the machinery of
Mandell, May, Schwede, and Shipley, we show that there is a "stable model
structure" on this category of diagram spectra which admits a monoidal Quillen
equivalence to the category of orthogonal G-spectra. We construct a second
"absolute stable model structure" which is Quillen equivalent to the "stable
model structure". Our main result is a concrete identification of the fibrant
objects in the absolute stable model structure. There is a model-theoretic
identification of the fibrant continuous functors in the absolute stable model
structure as functors Z such that for A in W_G the collection {Z(A smash S^W)}
form an Omega-G-prespectrum as W varies over the universe U. We show that a
functor is fibrant if and only if it takes G-homotopy pushouts to G-homotopy
pullbacks and is suitably compatible with equivariant Atiyah duality for orbit
spaces G/H_+ which embed in U. Our motivation for this work is the development
of a recognition principle for equivariant infinite loop spaces.Comment: This is the version published by Algebraic & Geometric Topology on 8
December 200
Embodiment, Transparency and the Disclosiveness of Failure
In this paper, I want to argue that embodiment is characterised by a plasticity which entails that it can include both the biological limb and the ‘artificial’ tool, as evidenced by recent research in cognitive science. Moreover, I want to claim that it is only in failure that the embodied limb and tool are phenomenologically distinct. I will go on to argue that this claim is essential for understanding the phenomenon of failed embodiment, such as that found within the clowning tradition, before concluding with a short provocation regarding the social and political implications of such a view
House of Commons Select Committee on Transport: Inquiry into Urban Congestion Charging
INTRODUCTION
This evidence, submitted to the Select Committee for its inquiry into Urban Congestion Charging, is based on my research into the subject, and professional involvement in studies of methods for managing the demand for urban travel, over the last twenty years. In the 1970s I was responsible, within the Greater London Council, for their studies of the use of comprehensive parking control, physical restriction of road space, and supplementary licensing (a low technology method of congestion charging) as methods of traffic restraint. At the same time, I was an adviser to the World Bank in its study of Singapore's area licensing scheme which is still the only congestion charging system in operation. In the 1980s I was an adviser to the US Transport Research Board in its investigation of appropriate methods for managing urban traffic, and to The MVA Consultancy in its study of electronic road pricing for Hong Kong. Since 1987 I have been involved, as a director of The MVA Consultancy, in a series of integrated transport studies in London (for the London Planning Advisory Committee), Birmingham, Edinburgh, Bristol and Merseyside, each of which has investigated the role of congestion charging as part of a wider transport strategy. I am currently directing a programme of research, funded by the Engineering and Physical Sciences Research Council, which is assessing the relative impact on urban road networks of different methods of imposing congestion charging, on their own and in combination with traffic signal control and bus priorities. This research has used Cambridge and York as case studies. In addition, I am currently acting as one of the technical advisers to the Department of Transport's study of congestion charging in London.
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Rearticulating the case for minority language rights
While advocacy of minority language rights (MLR) has become well established in sociolinguistics, language policy and planning and the wider human rights literature, it has also come under increased criticism in recent times for a number of key limitations. In this paper, I address directly three current key criticisms of the MLR movement. The first is a perceived tendency towards essentialism in articulations of language rights. The second is the apparent utopianism and artificiality of 'reversing language shift' in the face of wider social and political 'realities'. And the third is that the individual mobility of minority-language speakers is far better served by shifting to a majority language. While acknowledging the perspicacity of some of these arguments, I aim to rearticulate a defence of minority language rights that effectively addresses these key concerns. This requires, however, a sociohistorical/sociopolitical rather than a biological/ecological analysis of MLR. In addition, I will argue that a sociohistorical/sociopolitical defence of MLR can problematise the positions often adopted by minority language rights' critics themselves, particularly those who defend majoritarian forms of linguistic essentialism and those who sever the instrumental/identity aspects of language. Implications for language policy and planning will also be discussed
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