349 research outputs found
Field Strength Correlators For 2D Yang-Mills Over Riemann Surfaces
The path integral computation of field strength correlation functions for two
dimensional Yang-Mills theories over Riemann surfaces is studied. The
calculation is carried out by abelianization, which leads to correlators that
are topological. They are nontrivial as a result of the topological
obstructions to the abelianization. It is shown in the large N limit on the
sphere that the correlators undergo second order phase transitions at the
critical point. Our results are applied to a computation of contractible Wilson
loops.Comment: final version to appear in Int. Jour. Mod. Phys. A, minor
corrections, added a few comments on Wilson loops and non-abelian Stokes
theore
Solution of the two identical ion Penning trap final state
We have derived a closed form analytic expression for the asymptotic motion
of a pair of identical ions in a high precision Penning trap. The analytic
solution includes the effects of special relativity and the Coulomb interaction
between the ions. The existence and physical relevance of such a final state is
supported by a confluence of theoretical, experimental and numerical evidence.Comment: 5 pages and 2 figure
Uniqueness of the minimum of the free energy of the 2D Yang-Mills theory at large N
There has been some controversies at the large behaviour of the 2D
Yang-Mills and chiral 2D Yang-Mills theories. To be more specific, is there a
one parameter family of minima of the free energy in the strong region, or the
minimum is unique. We show that there is a missed equation which, added to the
known equations, makes the minimum unique.Comment: 8 pages,Late
Evaluation of the Free Energy of Two-Dimensional Yang-Mills Theory
The free energy in the weak-coupling phase of two-dimensional Yang-Mills
theory on a sphere for SO(N) and Sp(N) is evaluated in the 1/N expansion using
the techniques of Gross and Matytsin. Many features of Yang-Mills theory are
universal among different gauge groups in the large N limit, but significant
differences arise in subleading order in 1/N.Comment: 10 pages; no figures; LaTe
The Atlantic bluefin tuna: structure and competitiveness of Italian fishing in the international trade
In this paper after showing the productive and international trade background of the Atlantic bluefin tuna, we analyze the competitive position of Italy, important producer and exporter on world scale, compared with the main trade partners, carried out through competitiveness indexes based on trade data. The results highlight Italy's good competitive performance above all with Japan, which represents the main world reference market for the Italian product, but also with the United States, Malta and Turkey The Italian competitive advantage with these countries is stronger for the product taken into account. On the other hand, we can notice a competitive disadvantage with the traditional markets supplying bluefin tuna, and with Spain in particular The same is reckoned with the Southern Mediterranean countries which, in the last years, have contributed to increasing the world supply thanks to the spread of mariculture systems. In this background, the increasing interest in the Italian Atlantic bluefin tuna, by the United States in particular and by some Mediterranean countries and by Central Western Europe as well, could open new opportunities to the Italian trade
Quality certifications’ impact on wine industry assets performance
This study analyses the impact of third-party voluntary certifications on the asset of wineries operating in the Southern Italian regions. The study carried out both quantitative and qualitative approaches, with data extracted from the AIDA Bureau van Dijk International Database (including performance indicators). The analysed sector belongs to 11.02 ‘Manufacture of wine from grape’ of the Statistical classification of economic activities in the European Community (NACE). The econometric elaboration (regression) was carried out by means of STATA software 14. Comparing certified and no certified wineries, results show a better asset performance of certified wineries, confirmed by a positive relationship between higher revenues and bigger size. The adoption of voluntary certifications requires the presence of highly qualified people, capable of managing innovations of product or process. Wine managers should consider that the expected impacts of the adoption of voluntary certification are not independent from both targeted business scopes and institutional context where the winery operates, being strictly linked to specific market and seller strategic decisions, including customer centricity approaches. For what in our knowledge, this work is the first attempt in investigating the impact of voluntary certifications in the Sicilian wine industries. Results are thus of relevant importance and originality and able to suggest new insights on business assets management for the wine industry, enabling managers to better approach the decision to get certified through sustainable standards
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