2,865 research outputs found
Isotropy of the early universe from CMB anisotropies
The acoustic peak in the CMB power spectrum is sensitive to causal processes
and cosmological parameters in the early universe up to the time of last
scattering. We provide limits on correlated spatial variations of the peak
height and peak position and interpret these as constraints on the spatial
variation of the cosmological parameters (baryon density, cold dark matter
density and cosmological constant as well as the amplitude and tilt of the
original fluctuations). We utilize recent work of Hansen, Banday and Gorski
(HBG) who have studied the spatial isotropy of the power spectrum as measured
by WMAP by performing the power spectrum analysis on smaller patches of the
sky. We find that there is no statistically significant correlated asymmetry of
the peak. HBG have also provided preliminary indications of a preferred
direction in the lower angular momentum range(~ 2-40) and we show how possible
explanations of this asymmetry are severely constrained by the data on the
acoustic peak. Finally we show a possible non-gaussian feature in the data,
associated with a difference in the northern and southern galactic hemispheres.Comment: 14 pages, 3 figures, v.2 adds an extra relevant reference and commen
The elusive quest for balanced regional growth from Barlow to Brexit: lessons from partitioning regional employment growth in Great Britain
The British Government’s economic strategy for post-Brexit Britain of achieving balanced regional growth by “driving growth across the whole country” echoes the objectives set by the Barlow Report of 1940. The regional policies that followed the Barlow Report were heavily influenced by papers written for the Commission by G D A (later Sir Donald) MacDougall.
The first of these papers was included as an appendix to the report itself and introduced the shift-share methodology to the analysis of regional employment growth, and subsequently shown to be flawed.
The second paper considered the urban hierarchy and growth but was never fully developed. Consequently post-war regional policy focussed on the contribution of industrial structure to employment growth without fully taking into account the urban hierarchy or regional locations of that employment.
This article replaces the flawed shift-share methodology with multifactor partitioning (MFP) and applies it to regional employment growth for the period 1971-2012, a span of special interest because it largely coincides with British membership of the European Union (EU). The deficiencies in the second paper are addressed by introducing allometry to measure the employment growth of each region relative to that of Great Britain and then regression analysis to relate the allometries to distance from London.
The results of the two sets of analyses highlight the need for a multiple-factor, comprehensive, and integrated approach to regional policy and provide a benchmark against which to gauge the success of Britain's post-Brexit policy of driving future growth across the whole country
Baryon Masses in Chiral Perturbation Theory with Infrared Regularization
The baryon masses are examined in SU(3) chiral perturbation theory to third
order using the recently proposed infrared regularization scheme. Fourth order
is estimated by evaluating the dominant diagram. With this regularization the
magnitude of the loop integrals is reduced so that the convergence of the
series appears to be better than in the heavy baryon approach.Comment: The original third order calculation is supplemented by an estimate
of fourth order using just the dominant diagram. The convergence still
appears to be better than in the heavy baryon approach. To be published in
Phys. Rev. C. 15 pages latex, 2 postscript figure
A Newtonian Model for the Quantum Gravitational Back-Reaction on Inflation
Quantum gravitational back-reaction offers a simultaneous explanation for why
the cosmological constant is so small and a natural model of inflation in which
scalars play no role. In this talk I review previous work and present a simple
model of the mechanism in which the induced stress tensor behaves like negative
vacuum energy with a density proportional to . The model also highlights the essential role of
causality in back-reaction.Comment: 4 pages, LaTeX 2.6, no figures. Talk given at the International
Meeting on Quantum Gravity and Spectral Geometry, Naples, Italy, July 2-7,
200
Publication Trends in North-Eastern Indian Multi-Disciplinary Journal: A Content Analysis of Man and Society
Journal analysis has been an important tool to understand various facets of academic publishing trends. A content analysis of research published in Man and Society: A Journal of North-East Studies was conducted for Volumes I through XIV. A total of 20 issues of the bi-annually published journal were analyzed involving the placement of 116 articles in 9 substantive content categories revealing information about the authorship, types of research conducted as well as areas of research focus. In addition, the study has also examined the types and locations of institutions the authors are affiliated with. This has been done with a broad view to examine research focus and trends in the journal as a lens to understanding broader perspectives in scholarship and research in the Northeastern region. The findings indicate that the journal has stayed true to its mission of publishing articles across various disciplines pertaining to multiple issues of North-East India
Publication Trends in North-Eastern Indian Multi-Disciplinary Journal: A Content Analysis of Man and Society
Journal analysis has been an important tool to understand various facets of academic publishing trends. A content analysis of research published in Man and Society: A Journal of North-East Studies was conducted for Volumes I through XIV. A total of 20 issues of the bi-annually published journal were analyzed involving the placement of 116 articles in 9 substantive content categories revealing information about the authorship, types of research conducted as well as areas of research focus. In addition, the study has also examined the types and locations of institutions the authors are affiliated with. This has been done with a broad view to examine research focus and trends in the journal as a lens to understanding broader perspectives in scholarship and research in the Northeastern region. The findings indicate that the journal has stayed true to its mission of publishing articles across various disciplines pertaining to multiple issues of North-East India
Final state rescattering as a contribution to
We provide a new estimate of the long-distance component to the radiative
transition . Our mechanism involves the soft-scattering of
on-shell hadronic products of nonleptonic decay, as in the chain . We employ a phenomenological fit to scattering data
to estimate the effect. The specific intermediate states considered here modify
the decay rate at roughly the level, although
the underlying effect has the potential to be larger. Contrary to other
mechanisms of long distance physics which have been discussed in the
literature, this yields a non-negligible modification of the channel and hence will provide an uncertainty in the extraction of
. This mechanism also affects the isospin relation between the rates
for and and may generate CP
asymmetries at experimentally observable levels.Comment: 15 pages, RevTex, 3 figure
Photon-Photon Scattering, Pion Polarizability and Chiral Symmetry
Recent attempts to detect the pion polarizability via analysis of
measurements are examined. The connection
between calculations based on dispersion relations and on chiral perturbation
theory is established by matching the low energy chiral amplitude with that
given by a full dispersive treatment. Using the values for the polarizability
required by chiral symmetry, predicted and experimental cross sections are
shown to be in agreement.Comment: 21 pages(+10 figures available on request), LATEX, UMHEP-38
Cosmological Consequences of String Axions
Axion fluctuations generated during inflation lead to isocurvature and
non-Gaussian temperature fluctuations in the cosmic microwave background
radiation. Following a previous analysis for the model independent string axion
we consider the consequences of a measurement of these fluctuations for two
additional string axions. We do so independent of any cosmological assumptions
except for the axions being massless during inflation. The first axion has been
shown to solve the strong CP problem for most compactifications of the
heterotic string while the second axion, which does not solve the strong CP
problem, obeys a mass formula which is independent of the axion scale. We find
that if gravitational waves interpreted as arising from inflation are observed
by the PLANCK polarimetry experiment with a Hubble constant during inflation of
H_inf \apprge 10^13 GeV the existence of the first axion is ruled out and the
second axion cannot obey the scale independent mass formula. In an appendix we
quantitatively justify the often held assumption that temperature corrections
to the zero temperature QCD axion mass may be ignored for temperatures T
\apprle \Lambda_QCD.Comment: 27 pages, 4 figures; v2: References corrected; v3: Assumptions
simplified, minor corrections, conclusions unchange
On the Ultraviolet Behaviour of Newton's constant
We clarify a point concerning the ultraviolet behaviour of the Quantum Field
Theory of gravity, under the assumption of the existence of an ultraviolet
Fixed Point. We explain why Newton's constant should to scale like the inverse
of the square of the cutoff, even though it is technically inessential. As a
consequence of this behaviour, the existence of an UV Fixed Point would seem to
imply that gravity has a built-in UV cutoff when described in Planck units, but
not necessarily in other units.Comment: 8 pages; CQG class; minor changes and rearrangement
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