7,687 research outputs found
How Do Nonlinear Voids Affect Light Propagation ?
Propagation of light in a clumpy universe is examined. As an inhomogeneous
matter distribution, we take a spherical void surrounded by a dust shell where
the ``lost mass'' in the void is compensated by the shell. We study how the
angular-diameter distance behaves when such a structure exists. The
angular-diameter distance is calculated by integrating the Raychaudhuri
equation including the shear. An explicit expression for the junction condition
for the massive thin shell is calculated. We apply these results to a dust
shell embedded in a Friedmann universe and determine how the distance-redshift
relation is modified compared with that in the purely Friedmann universe. We
also study the distribution of distances in a universe filled with voids. We
show that the void-filled universe gives a larger distance than the FRW
universe by at if the size of the void is of the
Horizon radius.Comment: To appear in Prog. Theor. Phys. 10
Quantum Mechanics of Extended Objects
We propose a quantum mechanics of extended objects that accounts for the
finite extent of a particle defined via its Compton wavelength. The Hilbert
space representation theory of such a quantum mechanics is presented and this
representation is used to demonstrate the quantization of spacetime. The
quantum mechanics of extended objects is then applied to two paradigm examples,
namely, the fuzzy (extended object) harmonic oscillator and the Yukawa
potential. In the second example, we theoretically predict the phenomenological
coupling constant of the meson, which mediates the short range and
repulsive nucleon force, as well as the repulsive core radius.Comment: RevTex, 24 pages, 1 eps and 5 ps figures, format change
Is there still a strong CP problem?
The role of a chiral U(1) phase in the quark mass in QCD is analysed from
first principles. In operator formulation, there is a parity symmetry and the
phase can be removed by a change in the representation of the Dirac gamma
matrices. Moreover, these properties are also realized in a Pauli-Villars
regularized version of the theory. In the functional integral scenario,
attempts to remove the chiral phase by a chiral transformation are thought to
be obstructed by a nontrivial Jacobian arising from the fermion measure and the
chiral phase may therefore seem to break parity. But if one starts from the
regularized action with the chiral phase also present in the regulator mass
term, the Jacobian for a combined chiral rotation of quarks and regulators is
seen to be trivial and the phase can be removed by a combined chiral rotation.
This amounts to a taming of the strong CP problem.Comment: 6 pages, REVTeX; brief discussion available at
http://theory.saha.ernet.in/~mitra/scp.htm
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Scaling Up Primary Education Services in Rural Tamil Nadu: Public Investment Requirements and Reform
We attempt to address two key questions in this paper: 1) In terms of state-wide scaling up of rural services in the area of primary education, what will it cost financially and in terms of human resources to scale-up these services in all the rural areas of the state? And 2) What policy, institutional and governance reforms may be necessary so as to ensure proper service delivery? As is well known, merely constructing more schools, for instance, is not going to be enough; higher public investments in these areas needs to be accompanied by systemic reforms that will help overhaul the present service delivery system, including issues of control and oversight, for example
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Scaling Up Primary Education Services in Rural India: Public Investment Requirements and Policy Reform: Case Studies of Uttar Pradesh and Madhya Pradesh
We attempt to address two key questions in this paper: 1) In terms of state-wide scaling up of rural services (in Uttar Pradesh, and Madhya Pradesh) in the area of primary education, what will it cost financially and in terms of human resources to scale-up these services in all the rural areas of these two states? And 2) what policy, institutional and governance reforms may be necessary so as to ensure proper service delivery? As is well known, merely setting up more schools, for instance, is not going to be enough; higher public investments in these areas needs to be accompanied by systemic reforms that will help overhaul the present service delivery system, including issues of control and oversight, for example
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Scaling Up Primary Health Services in Rural India: Public Investment Requirements and Health Sector Reform: Case Studies of Uttar Pradesh and Madhya Pradesh
We attempt to address two key questions in this paper: 1) In terms of state-wide scaling up of rural services (in Uttar Pradesh, and Madhya Pradesh) in the area of primary health, what will it cost financially and in terms of human resources to scale-up these services in all the rural areas of these two states? And 2) What policy, institutional and governance reforms may be necessary so as to ensure proper service delivery? As is well known, merely setting up more health clinics, for instance, is not going to be enough; higher public investments in these areas needs to be accompanied by systemic reforms that will help overhaul the present service delivery system, including issues of control and oversight, for example
Recommended from our members
Scaling Up Primary Health Services in Rural Tamil Nadu: Public Investment Requirements and Health Sector Reform
We attempt to address two key questions in this paper: 1) In terms of state-wide scaling up of rural services in the area of primary health, what will it cost financially and in terms of human resources to scale-up these services in all the rural areas of the state? And 2) what policy, institutional and governance reforms may be necessary so as to ensure proper service delivery? As is well known, merely setting up more health clinics, for instance, is not going to be enough; higher public investments in these areas needs to be accompanied by systemic reforms that will help overhaul the present service delivery system, including issues of control and oversight, for example
Recommended from our members
Scaling Up Primary Education Services in Rural India
We attempt to address two key questions in this paper: 1) In terms of state-wide scaling up of rural services (in Uttar Pradesh, and Madhya Pradesh) in the area of primary education, what will it cost financially and in terms of human resources to scale-up these services in all the rural areas of these two states? And 2) what policy, institutional and governance reforms may be necessary so as to ensure proper service delivery? As is well known, merely setting up more schools, for instance, is not going to be enough; higher public investments in these areas needs to be accompanied by systemic reforms that will help overhaul the present service delivery system, including issues of control and oversight, for example
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Reaching the Millennium Development Goals in South Asia
The United Nations Millennium Development Goals (MDGs) set the stage for developing countries to reduce extreme poverty and the problems that accompany it, such as hunger, high rates of infant, child and maternal mortality, insufficient disease control, lack of education, illiteracy, gender disparity and environmental degradation. Each goal has a specific target level for progress, such as halving poverty or reducing infant mortality rates by two thirds. All goals are to be reached by 2015, using 1990 as the benchmark year. By setting a time frame and specific levels of reductions for a variety of indicators, progress towards the goals is measurable, if data on indicators is available. Tracking progress is an essential step towards meeting the goals, as problem areas can be identified only through monitoring and evaluation, and interventions and strategies can then be developed to target them. South Asia as a whole seems likely to halve poverty levels by 2015, due in large part to India's progress on this MDG indicator. However, the situation is not as promising in other areas, such as reduction of high rates of infant, under-five and maternal mortality. There are wide inter-country, inter-state and intra-state differences in levels of progress towards the goals throughout South Asia. In a country as large and as populous as India, tackling problems such as high maternal mortality rates at the state and even at the district levels could determine whether India as a whole achieves the MDGs. Over one billion of the roughly 1.37 billion residents of South Asia reside in India, which means that India's achievement of any of the goals brings South Asia as a whole a step closer towards regional goal attainment. For South Asia as whole and for India in particular, public spending must be increased in the areas of health, education, rural infrastructure and agricultural research and development. The Indian government under-invests in all of these areas. Not only must public spending be increased, but spending must be accompanied by reforms. Decentralization would lead to greater control and oversight, conditions necessary for accountability. There are only 11 years remaining to meet the MDGs. It is time for South Asian governments to focus on problem areas related to extreme poverty in the region, such as high rates of infant and maternal mortality, low primary school enrollment and completion rates, poor rural infrastructure and low rates of access to safe drinking water and sanitation, especially in rural areas
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Improving Access, Service Delivery and Efficiency of the Public Health System in Rural India
This book presents the findings of a project to evaluate the functioning of the National Rural Health Mission (NRHM) which was put together at the request of the Minister of Health and Family Welfare, Government of India to an International Advisory Panel (IAP) for the NRHM. The IAP was constituted to provide broad policy advice to the Ministry of Health on how best to achieve the key objectives of the NRHM. The principal activity under this project was to conduct a systematic evaluation of the performance of the NRHM in selected states of India relying on a mix of inputs: extensive data sets already collected by the Ministry of Health since the launch of the NRHM; new survey data which was collected; empirical analysis of the primary and secondary data; detailed interviews of health functionaries at the village, block and the district levels; documentation of key innovations, challenges and successes that have arisen in particular regions, and inputs from some of the members of the IAP, such as our experts on core reproductive, maternal, newborn and child health issues, nutrition, chronic diseases, and malaria among others. The project was undertaken in collaboration with the Indian Institute of Management (IIM) at Ahmedabad. It was decided to focus on three of NRHM‘s high-focus states, i.e. Madhya Pradesh (henceforth MP), Rajasthan (henceforth RJ) and Uttar Pradesh (henceforth UP)
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