965 research outputs found
Wrapping corrections for non-diagonal boundaries in AdS/CFT
We consider an open string stretched between a Y=0 brane and a Y_theta=0
brane. The latter brane is rotated with respect to the former by an angle
theta, and is described by a non-diagonal boundary S-matrix. This system
interpolates smoothly between the Y-Y (theta =0) and the Y-bar Y (theta = pi/2)
systems, which are described by diagonal boundary S-matrices. We use
integrability to compute the energies of one-particle states at weak coupling
up to leading wrapping order (4, 6 loops) as a function of the angle. The
results for the diagonal cases exactly match with those obtained previously.Comment: 21 pages, 1 figur
Rational blow-downs and smoothings of surface singularities
In this paper we give a necessary combinatorial condition for a
negative--definite plumbing tree to be suitable for rational blow--down, or to
be the graph of a complex surface singularity which admits a rational homology
disk smoothing. New examples of surface singularities with rational homology
disk smoothings are also presented; these include singularities with resolution
graph having valency four nodes.Comment: 61 pages, 28 figure
Constraining weak annihilation using semileptonic D decays
The recently measured semileptonic D_s decay rate can be used to constrain
weak annihilation (WA) effects in semileptonic D and B decays. We revisit the
theoretical predictions for inclusive semileptonic D_{(s)} decays using a
variety of quark mass schemes. The most reliable results are obtained if the
fits to B decay distributions are used to eliminate the charm quark mass
dependence, without using any specific charm mass scheme. Our fit to the
available data shows that WA is smaller than commonly assumed. There is no
indication that the WA octet contribution (which is better constrained than the
singlet contribution) dominates. The results constrain an important source of
uncertainty in the extraction of |Vub| from inclusive semileptonic B decays.Comment: 5 pages, 2 figures, published versio
COOPERATIVE MOVEMENTS SETTING EXAMPLE FOR CLASSIC TEAMWORKS OF COUNTRYSIDES IN TRANSYLVANIA
Cooperative movements assured economic welfare of villages, led them to the way of becoming real citizens in the first half of the XXth century. By that period we can say that for improving competitivity advancing coops, and their social role is necessary. In an active coop continuous modernization is needed. This is due to global challenges and multinational companies, and also smaller dominant ones. This is why Hangya cooperative organisations are to be remembered for being the first in the Carpatian basin from the late 19th century. Manufacturers can realize their interests by building their own organizations. This is the cooperation of separate farmers, today dealing with very complicated transnational organizations. Realizing these may be the way to improve livings in the countryside, especially in the agriculture. Joining the following forms of groups is a unique and necessary way to reach these. By this the conclusion is: there must be an integrated network system for production branches controlled by coops with cooperative tenets in Transylvania. For this historical examples of helping farmers remain separate, reach markets must be known and adopted into today’s circumstances.Cooperatives of Transylvania, Judiciary bases, Improving competitiveness, Integrated product channel, Security of income, Community/Rural/Urban Development, Industrial Organization,
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