A bound on the scale of spacetime noncommutativity from the reheating phase after inflation

In an approach to noncommutative gauge theories, where the full noncommutative behavior is delimited by the presence of the UV and IR cutoffs, we consider the possibility of describing a system at a temperature T in a box of size L. Employing a specific form of UV/IR relationship inherent in such an approach of restrictive noncommutativity, we derive, for a given temperature T, an upper bound on the parameter of spacetime noncommutativity Lambda_NC ~ |theta|^{-1/2}. Considering such epochs in the very early universe which are expected to reflect spacetime noncommutativity to a quite degree, like the reheating stage after inflation, or believable pre-inflation radiation-dominated epochs, the best limits on Lambda_NC are obtained. We also demonstrate how the nature and size of the thermal system (for instance, the Hubble distance versus the future event horizon) can affect our bounds.Comment: 9 pages, a reference added, to appear in PL

The economic regulation of quality in the Italian VQPRD sector: which perspectives?

The Appellation of Origin system is aimed at reducing consumer's information costs, assuring a minimum quality standard and wine typicity, as well as maintaining a diversified supply in order to satisfy consumer s tastes heterogeneity. The effectiveness of the system is menaced by quantity and quality uncertainty, free riding phenomena, vertical relationships complexity and hold- up risks. The long term risk of the drop of the collective reputation of the Appellation justifies the economic regulation of the supply by the sectorial Organizations. Thus, it is necessary to evaluate ther role in the construction of the competitive advantage of the quality wine system. Then, the question that we address in this paper is that of the effectiveness of the supply regulation of quantity and quality in the Italian system of Appellation of Origin. We analyze the current context of the Italian Appellation of Origin Chianti Classico and the mechanisms of the supply economic regulation. At first, we describe the structural and commercial characteristics of the Appellation, the vertical relationships among the agents, the trend of the most important economic indicators of the Appellation. Then, we provide an analysis of the current mechanisms of the economic regulation of supply, from the specific production requirement s to the role of the sectorial organisation in the Appellation quality strategy. Finally, we point out the problems and the possible evolutions of the Appellation of Origin's system, in the context of the Reform of the CMO of wine.Appellation of Origin, collective reputation, economic regulation of supply, sectorial organizations, Agribusiness,

A Rational Deconstruction of Landin's SECD Machine with the J Operator

Landin's SECD machine was the first abstract machine for applicative expressions, i.e., functional programs. Landin's J operator was the first control operator for functional languages, and was specified by an extension of the SECD machine. We present a family of evaluation functions corresponding to this extension of the SECD machine, using a series of elementary transformations (transformation into continu-ation-passing style (CPS) and defunctionalization, chiefly) and their left inverses (transformation into direct style and refunctionalization). To this end, we modernize the SECD machine into a bisimilar one that operates in lockstep with the original one but that (1) does not use a data stack and (2) uses the caller-save rather than the callee-save convention for environments. We also identify that the dump component of the SECD machine is managed in a callee-save way. The caller-save counterpart of the modernized SECD machine precisely corresponds to Thielecke's double-barrelled continuations and to Felleisen's encoding of J in terms of call/cc. We then variously characterize the J operator in terms of CPS and in terms of delimited-control operators in the CPS hierarchy. As a byproduct, we also present several reduction semantics for applicative expressions with the J operator, based on Curien's original calculus of explicit substitutions. These reduction semantics mechanically correspond to the modernized versions of the SECD machine and to the best of our knowledge, they provide the first syntactic theories of applicative expressions with the J operator

Legal security and credibility in agent based virtual enterprises

Recent trends in the field of Artificial Intelligence, brought along new ways of formalizing and expressing wills and declarations. Its application to Virtual Enterprises requires an analysis of the interactions among agents, frameworks and users, as well as technical and legal analysis, in order to discover the rules to be applied, to solve a particular problem under a prospective scenario. Credibility, trust and security issues must be taken under consideration, especially concerning authenticity, confidentiality, integrity and non-repudiation. In order to increase the use of agents in Virtual Enterprises, besides the analysis and research of legal solutions in the commercial arena, it is essential to assure that agents will meet requirements of credibility and trust, insuring a transparent and secure way for their commercial acting, now capable of generating legal relations. This paper shows how to construct a dynamic virtual world of complex and interacting entities or agents, in which fitness is judged by a quality of information criterion

Societal constitutionalism : alternatives to state-centred constitutional theory

Englische Fassung: Societal Constitutionalism: Alternatives to State-centred Constitutional theory? ("Storrs Lectures 2003/04" Yale Law School) In: Christian Joerges, Inge-Johanne Sand und Gunther Teubner (Hg.) Constitutionalism and Transnational Governance. Hart, Oxford 2004, 3-28. Und in: Ius et Lex 2004, S.31-50. Französische Fassung: Constitutionalisme sociétal et globalisation: Alternatives à la théorie constitutionelle centrée sur l'État. Themis 2005 (im Erscheinen) Italienische Fassung: Costituzionalismo societario: alternative alla teoria costituzionale stato-centrica. In: Gunther Teubner, Costituzionalismo societario. Armando, Roma 2005 (im Erscheinen). Spanische Fassung: Globalización y constitucionalismo social: alternativas a la teoría constitucionalista centrada en el Estado". In: Carlos Gómez-Jara Díez (Hg.), Teoría de sistemas y Derecho penal: Fundamentos y posibilidades de aplicación. Granada: Comares, 2005 (im Erscheinen) und in: Cancio Meliá und Bacigalupo Saggese (Hg.) Derecho penal y política transnacional. Barcelona: Atelier, 2005 (in Erscheinen)und in: Gunther Teubner, El Derecho como sistema autopoiético de la sociedad global, herausgegeben von Carlos Gómez-Jara Diez. Bogotá: Universidad Externado de Colombia, 2005 (im Erscheinen) und Lima: ARA Editores, 2005 (im Erscheinen) Polnische Fassung: Konstytucjonalizm spoleczny: Alternatywy dla teorii konstitucyjnej nakierowanej na panstwo. Ius et Lex 3, 2004, S.5-27

Nordic Electricity Congestion's Arrangement as a Model for Europe: Physical Constraints or Operators' Opportunity

Nordic Electricity Congestion's Arrangement as a Model for Europe: Physical Constraints or Operators' Opportunit

How competition controls team production: The case of fishing firms

Under team production, those who monitor individual productivity are usually the only ones compensated with a residual that varies with the performance of the team. This pattern is efficient, as is shown by the prevalence of conventional firms, except for small teams and when specialized monitoring is ineffective. Profit sharing in repeated team production induces all team members to take disciplinary action against underperformers through switching and separation decisions, however. Such action provides effective self-enforcemnt when the markets for team members are competitive, even for large teams using specialized monitoring. The traditional share system of fishing firms shows that for this competition to provide powerful enough incentives the costs of switching teams and measuring team productivity must be bellow. Risk allocation may constrain the organizational design defined by the use of a share system. It does not account for its existence, however.Theory of the firm, team production, share contracts, profit sharing, remuneration systems, self-enforcement, fishing firms

Better Off Working? Work, Poverty And Benefit Cycling

A study of the work experiences of a group of low-skilled workers over five years. Concern has been growing about the extent to which paid work is an effective route out of poverty and the extent of churning between work and benefits that can result in recurrent poverty. Using both interview and survey data, this report examines work pathways, experiences of retention and progression, and feelings of financial strain among a group of lone parents and former long-term unemployed people who have entered work. The report covers: • people’s perceptions of poverty and financial strain and how this relates to their movements in and out of work; • people’s trajectories in work and the factors facilitating or constraining work retention; • the relationship between work trajectories and moving into ‘better work’; • what enables or constrains people in their attempts to progress in work; and • tensions and trade-offs between retention and progression