1,893 research outputs found

    The elusive quest for balanced regional growth from Barlow to Brexit: lessons from partitioning regional employment growth in Great Britain

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    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

    Final state rescattering as a contribution to BργB \to \rho \gamma

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    We provide a new estimate of the long-distance component to the radiative transition BργB \to \rho \gamma. Our mechanism involves the soft-scattering of on-shell hadronic products of nonleptonic BB decay, as in the chain BρρργB \to \rho\rho \to \rho\gamma. We employ a phenomenological fit to scattering data to estimate the effect. The specific intermediate states considered here modify the BργB \to \rho \gamma decay rate at roughly the 585 \to 8% 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 B0ρ0γB^0 \to \rho^0 \gamma channel and hence will provide an uncertainty in the extraction of VtdV_{td}. This mechanism also affects the isospin relation between the rates for BργB^- \to \rho^-\gamma and B0ρ0γB^0 \to \rho^0 \gamma and may generate CP asymmetries at experimentally observable levels.Comment: 15 pages, RevTex, 3 figure

    Photon-Photon Scattering, Pion Polarizability and Chiral Symmetry

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    Recent attempts to detect the pion polarizability via analysis of γγππ\gamma\gamma\rightarrow\pi\pi 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

    CPT violation and B-meson oscillations

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    Recent evidence for anomalous CP violation in B-meson oscillations can be interpreted as resulting from CPT violation. This yields the first sensitivity to CPT violation in the B_s^0 system, with the relevant coefficient for CPT violation constrained at the level of parts in 10^{12}.Comment: 4 pages two-column REVTeX; Rapid Communications, Physical Review D, in pres

    Phenomenology of the Equivalence Principle with Light Scalars

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    Light scalar particles with couplings of sub-gravitational strength, which can generically be called 'dilatons', can produce violations of the equivalence principle. However, in order to understand experimental sensitivities one must know the coupling of these scalars to atomic systems. We report here on a study of the required couplings. We give a general Lagrangian with five independent dilaton parameters and calculate the "dilaton charge" of atomic systems for each of these. Two combinations are particularly important. One is due to the variations in the nuclear binding energy, with a sensitivity scaling with the atomic number as A1/3A^{-1/3}. The other is due to electromagnetism. We compare limits on the dilaton parameters from existing experiments.Comment: 5 page

    On the Ultraviolet Behaviour of Newton's constant

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    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

    The Electromagnetic Mass Differences of Pions and Kaons

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    We use the Cottingham method to calculate the pion and kaon electromagnetic mass differences with as few model dependent inputs as possible. The constraints of chiral symmetry at low energy, QCD at high energy and experimental data in between are used in the dispersion relation. We find excellent agreement with experiment for the pion mass difference. The kaon mass difference exhibits a strong violation of the lowest order prediction of Dashen's theorem, in qualitative agreement with several other recent calculations.Comment: 40 pages, Latex, needs axodraw. and psfig. macros, 4 figure

    Weak Hyperon Decays: Quark Sea and SU(3) Symmetry Breaking

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    An explanation of the difference in the values of the apparent f/df/d ratios for the S- and P- wave amplitudes of nonleptonic hyperon decays is proposed. The argument is formulated in the framework of the standard pole model with (56,0+)(56,0^{+}) ground-state and (70,1)(70,1^{-}) excited baryons as intermediate states for the P- and S- waves respectively. Under the assumption that the dominant part of the deviation of (f/d)Pwave(f/d)_{P-wave} from 1-1 is due to large quark sea effects, SU(3)SU(3) symmetry breaking in energy denominators is shown to lead to a prediction for (f/d)Swave(f/d)_{S-wave} which is in excellent agreement with experiment. This corroborates our previous unitarity calculations which indicated that the matrix elements of the parity conserving weak Hamiltonian between the ground-state baryons are characterized by f0/d01.6f_{0}/d_{0} \approx -1.6 or more. A brief discussion of the problem of the relative size of S- and P- wave amplitudes is given. Finally, implications for weak radiative hyperon decays are also discussed.Comment: 26 pages, LATEX, 1647/PH IFJ Krako

    On the correspondence between the classical and quantum gravity

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    The relationship between the classical and quantum theories of gravity is reexamined. The value of the gravitational potential defined with the help of the two-particle scattering amplitudes is shown to be in disagreement with the classical result of General Relativity given by the Schwarzschild solution. It is shown also that the potential so defined fails to describe whatever non-Newtonian interactions of macroscopic bodies. An alternative interpretation of the 0\hbar^0-order part of the loop corrections is given directly in terms of the effective action. Gauge independence of that part of the one-loop radiative corrections to the gravitational form factors of the scalar particle is proved, justifying the interpretation proposed.Comment: Latex 2.09, 3 ps. figures, 17 page

    Equilibrium configurations for quark-diquark stars and the problem of Her X-1 mass

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    We report new calculations of the physical properties of a quark-diquark plasma. A vacuum contribution is taken into account and is responsible for the appearance of a stable state at zero pressure and at a baryon density of about 2.2 times the nuclear matter density in this model. The resulting equation of state was used to integrate numerically the Tolman-Oppenheimer-Volkoff equations. The mass-radius relationship has been derived from a series of equilibrium configurations constituted by a mixture of quarks and diquarks. These stellar models, which are representative of a whole class, may be helpful to understand the possible compactness of the X-ray source Her X-1 and related objects.Comment: 15 pp., PlainTex file + 3 figures available upon request at [email protected]. Submitted to Int. Jour. Mod. Phys.
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