15,634 research outputs found
The Dualizing Spectrum, II
To an inclusion topological groups H->G, we associate a naive G-spectrum. The
special case when H=G gives the dualizing spectrum D_G introduced by the author
in the first paper of this series. The main application will be to give a
purely homotopy theoretic construction of Poincare embeddings in stable
codimension.Comment: Fixed an array of typo
Poincare submersions
We prove two kinds of fibering theorems for maps X --> P, where X and P are
Poincare spaces. The special case of P = S^1 yields a Poincare duality analogue
of the fibering theorem of Browder and Levine.Comment: Published by Algebraic and Geometric Topology at
http://www.maths.warwick.ac.uk/agt/AGTVol5/agt-5-2.abs.html Version 5:
Statement of Theorem B corrected, see footnote p2
Coarse-grained entropy and causal holographic information in AdS/CFT
We propose bulk duals for certain coarse-grained entropies of boundary
regions. The `one-point entropy' is defined in the conformal field theory by
maximizing the entropy in a domain of dependence while fixing the one-point
functions. We conjecture that this is dual to the area of the edge of the
region causally accessible to the domain of dependence (i.e. the `causal
holographic information' of Hubeny and Rangamani). The `future one-point
entropy' is defined by generalizing this conjecture to future domains of
dependence and their corresponding bulk regions. We show that the future
one-point entropy obeys a nontrivial second law. If our conjecture is true,
this answers the question "What is the field theory dual of Hawking's area
theorem?"Comment: 43 pages, 9 figures. v3: minor changes suggested by referee v2: added
a few additional reference
List Size, Standards and Perfromance in General Practice - A Pilot Study in the South East Thames Region
This is a report of a piolt study carried out among 155 general practitioner trainers in South East Thames region. Similar pilot studies have been carried out among trainers in four other regions on England. Separate reports have been prepared for each of the five regions, together with a summary report comparing the findings among the regions. The pilot studies were funded by the DHSS and carried out by staff of the Health Services Research Unit at the University of Kent at Camterbury
Structural characterization of YBa(2)Cu(3)O(7)/Y(2)O(3) composite films
Using 4-circle x-ray diffraction and transmission electron microscopy we have
studied the microstructure and in-plane orientation of the phases present in
thin film composite mixtures of YBa(2)Cu(3)O(7) and Y(2)O(3). We see a high
degree of in-plane orientation and have verified a previous prediction for the
in-plane order of Y(2)BaCuO(5) on (110) MgO. Transmission electron microscopy
shows the composite films to be a mixture of two phases, with YBCO grain sizes
of 1 micron. We have also compared our observations of the in-plane order to
the predictions of a modified near coincidence site lattice model.Comment: To be published in Journal of Materials Research, (4 pages, 4 jpeg
figures
On the homotopy invariance of configuration spaces
For a closed PL manifold M, we consider the configuration space F(M,k) of
ordered k-tuples of distinct points in M. We show that a suitable iterated
suspension of F(M,k) is a homotopy invariant of M. The number of suspensions we
require depends on three parameters: the number of points k, the dimension of M
and the connectivity of M. Our proof uses a mixture of Poincare embedding
theory and fiberwise algebraic topology.Comment: Published by Algebraic and Geometric Topology at
http://www.maths.warwick.ac.uk/agt/AGTVol4/agt-4-35.abs.htm
Spherical alterations of handles: embedding the manifold plus construction
A key tool in our earlier work on ends of manifolds high-dimensional
manifolds was an ability to embed cobordisms provided by the Quillen Plus
Construction into those ends. Here we develop a `spherical modification' trick
which provides a constructive approach to obtaining such embeddings. More
importantly, this approach allows for more general embedding results. In this
paper we develop generalizations of the plus construction and show how the
corresponding cobordisms can be embedded in manifolds satisfying appropriate
fundamental group properties. Results obtained here play an important role in
our ongoing study of noncompact manifolds.Comment: This final version will appear in Algebraic & Geometric Topology.
Small corrections, including a fix to the statement of Theorem 5.3. 22 pages,
4 figure
Results of literature search on dielectric properties and electron interaction phenomena related to spacecraft charging
The objective of the literature search was to determine the required material properties and electron interaction parameters needed for modeling charge buildup and breakdown in insulators. A brief overview of the results of the literature search is given. A partial list of the references covered is included in a bibliography. Although inorganic insulators were also considered in the search, coverage is limited to the organics, primarily Kapton and Teflon
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