880 research outputs found
Access to Capital: Milwaukee's Continuing Small Business Lending Gaps
This study provides a detailed review of small business lending in Milwaukee, Wisconsin and illustrates how this new data set can be utilized to assess small business lending in virtually any local market. Milwaukee is a fairly typical industrial community that has been hit hard by decades of disinvestment but which also has been the location of many successful community reinvestment initiatives in recent years (Squires and O'Connor 2001). Previous research found that among the nation's fifty largest metropolitan areas Milwaukee had the smallest share of small business loans going to low- and moderate-income areas (Norman 1998). Lending to small businesses, that is firms with assets below $1 million, was also found to be below nationwide levels. Small business lending has also been concentrated in white communities with black and Hispanic communities receiving relatively small shares of such loans and loan dollars. But lenders vary dramatically in Milwaukee in terms of the distribution of their small business loans by neighborhood income level (Squires and O'Connor 1999). This study examines changes in small business lending patterns in Milwaukee between 1996, when these data first became available, and 1999, the most recent data that are available
Isotropy and Stability of the Brane
We reexamine Wald's no-hair theorem for global anisotropy in the brane world
scenarios. We derive a set of sufficient conditions which must be satisfied by
the brane matter and bulk metric so that a homogeneous and anisotropic brane
asymptotically evolves to a de Sitter spacetime in the presence of a positive
cosmological constant on the brane. We discuss the violations of these
sufficient conditions and we show that a negative nonlocal energy density or
the presence of strong anisotropic stress (i.e., a magnetic field) may lead the
brane to collapse. We discuss the generality of these conditions.Comment: 8 pages, 2 figures, corrected some typos and titl
Scalar brane backgrounds in higher order curvature gravity
We investigate maximally symmetric brane world solutions with a scalar field.
Five-dimensional bulk gravity is described by a general lagrangian which yields
field equations containing no higher than second order derivatives. This
includes the Gauss-Bonnet combination for the graviton. Stability and
gravitational properties of such solutions are considered, and we particularily
emphasise the modifications induced by the higher order terms. In particular it
is shown that higher curvature corrections to Einstein theory can give rise to
instabilities in brane world solutions. A method for analytically obtaining the
general solution for such actions is outlined. Genericaly, the requirement of a
finite volume element together with the absence of a naked singularity in the
bulk imposes fine-tuning of the brane tension. A model with a moduli scalar
field is analysed in detail and we address questions of instability and
non-singular self-tuning solutions. In particular, we discuss a case with a
normalisable zero mode but infinite volume element.Comment: published versio
Dialectics and difference: against Harvey's dialectical post-Marxism
David Harvey`s recent book, Justice, nature and the geography of difference (JNGD), engages with a central philosophical debate that continues to dominate human geography: the tension between the radical Marxist project of recent decades and the apparently disempowering relativism and `play of difference' of postmodern thought. In this book, Harvey continues to argue for a revised `post-Marxist' approach in human geography which remains based on Hegelian-Marxian principles of dialectical thought. This article develops a critique of that stance, drawing on the work of Jacques Derrida, Gilles Deleuze and Felix Guattari. I argue that dialectical thinking, as well as Harvey's version of `post-Marxism', has been undermined by the wide-ranging `post-' critique. I suggest that Harvey has failed to appreciate the full force of this critique and the implications it has for `post-Marxist' ontology and epistemology. I argue that `post-Marxism', along with much contemporary human geography, is constrained by an inflexible ontology which excessively prioritizes space in the theory produced, and which implements inflexible concepts. Instead, using the insights of several `post-' writers, I contend there is a need to develop an ontology of `context' leading to the production of `contextual theories'. Such theories utilize flexible concepts in a multilayered understanding of ontology and epistemology. I compare how an approach which produces a `contextual theory' might lead to more politically empowering theory than `post-Marxism' with reference to one of Harvey's case studies in JNGD
Brane World Dynamics and Conformal Bulk Fields
In the Randall-Sundrum scenario we investigate the dynamics of a spherically
symmetric 3-brane world when matter fields are present in the bulk. To analyze
the 5-dimensional Einstein equations we employ a global conformal
transformation whose factor characterizes the symmetric warp. We find a
new set of exact dynamical collapse solutions which localize gravity in the
vicinity of the brane for a stress-energy tensor of conformal weight -4 and a
warp factor that depends only on the coordinate of the fifth dimension.
Geometries which describe the dynamics of inhomogeneous dust and generalized
dark radiation on the brane are shown to belong to this set. The conditions for
singular or globally regular behavior and the static marginally bound limits
are discussed for these examples. Also explicitly demonstrated is complete
consistency with the effective point of view of a 4-dimensional observer who is
confined to the brane and makes the same assumptions about the bulk degrees of
freedom.Comment: 26 pages, latex, no figures. Minor revisions. Some references added.
Revised version to appear in Phys. Rev.
Black holes on thick branes
The interplay between topological defects (branes) and black holes has been a
subject of recent study, motivated in part by interest in brane-world
scenarios. In this paper we analyze in detail the description of a black hole
bound to a domain wall (a two-brane in four dimensions), for which an exact
description in the limit of zero wall thickness has been given recently. We
show how to smooth this singular solution with a thick domain wall. We also
show that charged extremal black holes of a size (roughly) smaller than the
brane thickness expel the wall, thereby extending the phenomenon of flux
expulsion. Finally, we analyze the process of black hole nucleation {\it on} a
domain wall, and argue that it is preferred over a previously studied mechanism
of black hole nucleation {\it away} from the wall.Comment: 22 pages revtex, 4 figures, comments adde
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