44,939 research outputs found
Extending tensors on polar manifolds
Let be a Riemannian manifold with a polar action by the Lie group ,
with section and generalized Weyl group . We show that
restriction to is a surjective map from the set of smooth
-invariant tensors on onto the set of smooth -invariant tensors on
. Moreover, we show that every smooth -invariant Riemannian metric
on can be extended to a smooth -invariant Riemannian metric on
with respect to which the -action remains polar with the same section
.Comment: arXiv admin note: text overlap with arXiv:1205.476
Pairing correlations with single Cooper pair transfer to individual quantal states
With the help of the static and dynamic mean field spectroscopic amplitudes,
taking into account successive and simultaneous transfer channels properly
corrected because of non-orthogonality effects, as well as describing the
associated elastic channels in terms of experimentally determined optical
potentials, one obtains absolute, two-particle transfer differential cross
sections which provide an overall account of the data within experimental
errors. One of the first results connected with such quantitative studies of
pairing correlations in nuclei is the observation of phonon mediated pairing in
the exotic halo nucleus Li, and the associated discovery of a new
mechanism to break nuclear gauge symmetry: bootstrap, pigmy-resonance-mediated
Cooper pair binding.Comment: Contributed chapter in "50 Years of Nuclear BCS", edited by R. A.
Broglia and V. Zelevinsk
Are small Sub-Sahara African farmers willing to pay for vegetative propagated orange fleshed sweetpotato planting material? Evidence from Central Mozambique
This paper evaluates farmers’ willingness to pay (WTP) for the vegetative propagated orange fleshed sweetpotato (OFSP) planting material that is many times considered as a public good. Famers’ WTP for OFSP vines was elicited by conducting a real choice experiment (RCE) among 121 small sweetpotato growers in central Mozambique with prior experience growing OFSP but with no participation in OFSP vine distributions in the previous 3 years of the experiment. Results reveals a higher farmers’ willingness to pay for OFSP varieties (US 0.03) and compared to the traditional subsidized price of clean sweetpotato vines (US$ 0.06) used in Mozambique. These results may encourage formation of a network of private vine multipliers that would supply permanently OFSP planting material in wider areas.Agricultural and Food Policy, Community/Rural/Urban Development, Consumer/Household Economics, Farm Management, Food Security and Poverty, Health Economics and Policy, International Development, Production Economics, Q16,
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