4,435 research outputs found
Neutrino Masses and Mixing in Brane-World Theories
We present a comprehensive study of five-dimensional brane-world models for
neutrino physics based on flat compactifications. Particular emphasis is put on
the inclusion of bulk mass terms. We derive a number of general results for
such brane-world models with bulk mass terms. In particular, in the limit of
small brane-bulk couplings, the electroweak eigenstates are predominantly given
as a superposition of three light states with non-trivial small admixtures of
bulk states. As a consequence, neutrinos can undergo standard oscillations as
well as oscillation into bulk Kaluza-Klein states. We use this structure to
construct a specific model based on Z_2 orbifolding and bulk Majorana masses
which is compatible with all observed oscillation phenomena. The solar neutrino
deficit is explained by oscillations into sterile bulk states while the
atmospheric neutrino deficit is due to mu - tau oscillations with naturally
maximal mixing. In addition, the model can accommodate the LSND result and a
significant neutrino dark matter component. We also analyze the constraints
from supernova energy loss on neutrino brane-world theories and show that our
specific model is consistent with these constraints.Comment: 45 pages, Latex, 1 eps-figur
The Evolution of Sustainable Development in Scotland:A case study of Community Right-to-buy Law and Policy 2003–2018
Effective ownership, management and access to land are central for sustainable development and can impact significantly on the opportunities for local enterprise. In 1998, Scotland’s Land Reform Policy Group concluded that ‘Land reform is needed on the grounds of fairness and to secure the public good’ Consequently, Scotland has introduced various schemes that facilitate or compel the transfer of land from an existing landowner to a community body. Sustainable development is a primary objective of all these regimes making them exceptional both in UK and global terms and worthy of in depth examination. This article critically explores how the laws and policies relating to sustainable development within these community right-to-buy regimes have matured and evolved from their introduction in 2003 to the present. It reveals the beginning of a fourth era in sustainable development policy in Scotland which moves away from a single ‘one size fits all’ approach to one where both sustainable development itself and wider sustainable development equations are tailored to land-use in Scotland and to the needs of each of the different community right-to-buy regimes. These developments evidence a significant maturity in the implementation and delivery of sustainable development in Scotland
More Than Money: Making a Difference With Assistance Beyond the Grant
Examines foundation efforts beyond grantmaking such as training, advocacy, and new investment strategies to increase grantee effectiveness and impact. Assesses the benefits of such help, grantees' views, and implications. Includes case studies
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