1,748 research outputs found

    Soft masses in superstring models with anomalous U(1) symmetries

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    We analyze the general structure of soft scalar masses emerging in superstring models involving anomalous U(1) symmetries, with the aim of characterizing more systematically the circumstances under which they can happen to be flavor universal. We consider both heterotic orbifold and intersecting brane models, possibly with several anomalous and non-anomalous spontaneously broken U(1) symmetries. The hidden sector is assumed to consist of the universal dilaton, Kahler class and complex structure moduli, which are supposed to break supersymmetry, and a minimal set of Higgs fields which compensate the Fayet-Iliopoulos terms. We leave the superpotential that is supposed to stabilize the hidden sector fields unspecified, but we carefully take into account the relations implied by gauge invariance and the constraints required for the existence of a metastable vacuum with vanishing cosmological constant. The results are parametrized in terms of a constrained Goldstino direction, suitably defined effective modular weights, and the U(1) charges and shifts. We show that the effect induced by vector multiplets strongly depends on the functional form of the Kahler potential for the Higgs fields. We find in particular that whenever these are charged matter fields, like in heterotic models, the effect is non-trivial, whereas when they are shifting moduli fields, like in certain intersecting brane models, the effect may vanish.Comment: 35 pages, LaTe

    Remarks on twisted theories with matter

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    We investigate some aspects of N=2 twisted theories with matter hypermultiplets in the fundamental representation of the gauge group. A consistent formulation of these theories on a general four-manifold requires turning on a particular magnetic flux, which we write down explicitly in the case of SU(2k). We obtain the blowup formula and show that the blowup function is given by a hyperelliptic sigma-function with singular characteristic. We compute the contact terms and find, as a corollary, interesting identities between hyperelliptic Theta functions.Comment: 18 pages, harvmac, one figur

    Constraints for the existence of flat and stable non-supersymmetric vacua in supergravity

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    We further develop on the study of the conditions for the existence of locally stable non-supersymmetric vacua with vanishing cosmological constant in supergravity models involving only chiral superfields. Starting from the two necessary conditions for flatness and stability derived in a previous paper (which involve the Kahler metric and its Riemann tensor contracted with the supersymmetry breaking auxiliary fields) we show that the implications of these constraints can be worked out exactly not only for factorizable scalar manifolds, but also for symmetric coset manifolds. In both cases, the conditions imply a strong restriction on the Kahler geometry and constrain the vector of auxiliary fields defining the Goldstino direction to lie in a certain cone. We then apply these results to the various homogeneous coset manifolds spanned by the moduli and untwisted matter fields arising in string compactifications, and discuss their implications. Finally, we also discuss what can be said for completely arbitrary scalar manifolds, and derive in this more general case some explicit but weaker restrictions on the Kahler geometry.Comment: 22 pages, Latex, no figure

    Minimal Stability in Maximal Supergravity

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    Recently, it has been shown that maximal supergravity allows for non-supersymmetric AdS critical points that are perturbatively stable. We investigate this phenomenon of stability without supersymmetry from the sGoldstino point of view. In particular, we calculate the projection of the mass matrix onto the sGoldstino directions, and derive the necessary conditions for stability. Indeed we find a narrow window allowing for stable SUSY breaking points. As a by-product of our analysis, we find that it seems impossible to perturb supersymmetric critical points into non-supersymmetric ones: there is a minimal amount of SUSY breaking in maximal supergravity.Comment: 27 pages, 1 figure. v2: two typos corrected, published versio

    GP Financial Management Capacity and PRI Financial Management Reform Efforts in West Bengal

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    The State of West Bengal in its Annual Financial Statement of 2009-2010 called for “decentralization with accountability.” In addition to an expanded welfare system and the promotion of self-reliance at the local level, the State has been concerned with improving livelihoods through significantly enhanced funding to its local governments. To be effective, decentralization should move to the level of villages in rural areas in addition to accommodating urban municipalities. The Government of West Bengal (GOWB) has a strong interest in increasing the service delivery to constituents and has encouraged development in the area of financial management by providing incentives, training, computerization and the dissemination of good practice information for rural local governments (PRIs) in order to advance such delivery. This report provides a detailed assessment of the current state of budgeting and financial management capacity of the GOWB PRIs, an assessment of PRI financial management reforms, and focused attention to the capacity of the GPs to manage budgets and fiscal flow. Results from this work support development of a new grant program. The report also highlights budgeting and financial management issues relevant to creating an efficient flow of funds in such a grant program, given the capacity witnessed in GOWB rural local governments. Also, benchmarks that might be considered in a new grant program are provided

    GP Financial Management Capacity and PRI Financial Management Reform Efforts in West Bengal

    Get PDF
    The State of West Bengal in its Annual Financial Statement of 2009-2010 called for “decentralization with accountability.” In addition to an expanded welfare system and the promotion of self-reliance at the local level, the State has been concerned with improving livelihoods through significantly enhanced funding to its local governments. To be effective, decentralization should move to the level of villages in rural areas in addition to accommodating urban municipalities. The Government of West Bengal (GOWB) has a strong interest in increasing the service delivery to constituents and has encouraged development in the area of financial management by providing incentives, training, computerization and the dissemination of good practice information for rural local governments (PRIs) in order to advance such delivery. This report provides a detailed assessment of the current state of budgeting and financial management capacity of the GOWB PRIs, an assessment of PRI financial management reforms, and focused attention to the capacity of the GPs to manage budgets and fiscal flow. Results from this work support development of a new grant program. The report also highlights budgeting and financial management issues relevant to creating an efficient flow of funds in such a grant program, given the capacity witnessed in GOWB rural local governments. Also, benchmarks that might be considered in a new grant program are provided

    An international perspective on the determinants of local government fragmentation

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    The main questions addressed in this paper are the identification of the main determinants of jurisdictional fragmentation as presently observed across countries and how well those findings line up with the predictions of the expanded standard model of optimal jurisdiction size. To our knowledge, to date, there does not exit a rigorous study analyzing the cross-country determinants of fragmentation in the way this issue has been previously analyzed for some particular countries. At the outset, country fixed effects can be expected to loom large and powerful. Each country with its own history conditioned by a myriad of details, including colonial legacies, geography or ethnic and linguistic fragmentation, are likely to have contributed to heterogeneous levels of fragmentation. These factors could all be summarized in what is often termed the long shadow or the “dead hand” of history. Indeed, some countries may still have the same vertical structure of government that they had many decades ago. But there are also many countries that have changed their governmental structures over the years. So in this paper we would like to find out what may the common determinants that have led to those changes, and also perhaps to help us better understand if those common determinants can also be used to explain why other countries have changed so little. The rest of this paper is organized as follows. In section 2 we offer a simple extension of the conventional model for optimal jurisdiction size. In section 3 we review the literature on government fragmentation and its impact. In section 4 we outline the empirical model proposed for the analysis of jurisdictional fragmentation. In section 5 we present the results from our estimations. We conclude in section 6
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