A topological invariant of RG flows in 2D integrable quantum field theories

We construct a topological invariant of the renormalization group trajectories of a large class of 2D quantum integrable models, described by the thermodynamic Bethe ansatz approach. A geometrical description of this invariant in terms of triangulations of three-dimensional manifolds is proposed and associated dilogarithm identities are proven.Comment: 12 pages, 6 figures. Presented at the Euroconference on New Symmetries in Statistical Mech. and Cond. Mat. Physics, Torino, July 20- August 1 1998. typos correcte

Gauged O(n) spin models in one dimension

We consider a gauged O(n) spin model, n >= 2, in one dimension which contains both the pure O(n) and RP(n-1) models and which interpolates between them. We show that this model is equivalent to the non-interacting sum of the O(n) and Ising models. We derive the mass spectrum that scales in the continuum limit, and demonstrate that there are two universality classes, one of which contains the O(n) and RP(n-1) models and the other which has a tuneable parameter but which is degenerate in the sense that it arises from the direct sum of the O(n) and Ising models.Comment: 9 pages, no figures, LaTeX sourc

How uncertain policy regulations affect germplasm acquisition and distribution?

A study of the impact of the in-trust agreements demonstrated the importance of a clear legal environment for the genebanks. Requests for repatriation of rice germplasm from the International Rice Research Institute peaked in 1994, during the period of uncertainty. This coincided with a period of decline in acquisitions by the genebank. The signing of the in-trust agreements led to a significant decline in repatriation requests. The analysis suggests that the size of the IRRI rice collection could have continued to decline if it were not for the signing of the in-trust agreements. Results moreover confirm the central role of Bioversity and policy research in the negotiations process. Concepts developed during the ITA negotiations contributed towards subsequent multilateral negotiations that eventually culminated in the International Treaty on Plant Genetic Resources

Simple and direct communication of dynamical supersymmetry breaking

We present a complete, calculable, and phenomenologically viable model of dynamical supersymmetry breaking. The model is a simple extension of the so called 3- 2 model, with gauge group SU(3) × SU(2) × GSM and the MSSM fields directly coupled to the hidden sector SU(2) vector fields. Sfermion masses are universal, thus solving the supersymmetric flavour problem, and gaugino masses are not suppressed, in fact they are predicted to be of the same order as sfermion masses. Sizeable contributions to the MSSM A-terms can be generated, depending on the size of some free couplings. As a byproduct, we show some properties of a class of models with n pairs of Higgs doublets

Astreintes and Italian Law

This essay analyses the transposition path into Italian law of the French measure of astreintes, which are an indirect coercive method aimed to force the debtor to fulfill the obligation. The modern configuration has led to the adoption of judgments such as the one related to the “Case Facebook” (Order of the Court of Reggio Emilia, 15 April 2015), involving the urgency protection provided by art. 700 c.c.p. relatively to the hypothesis of defamation on Facebook or other Social Networking Sites. The astreinte find an equal in the Anglo-Saxon sort, by the contempt of court, and in the German one, through the Zwangsstrafen, which led, after several transposition attempts into national law (among which stands out the “Project Carnelutti” of 1926), to the current forecast referred to art. 614 bis c.c.p., introduced by art. 49 of Law 18 June 2009 n. 69. An application issue of the astreinte in Italy concerns its potential struggle with the internal public order: in Italy, there isn’t any provision of punitive damages outlined in common law systems, so that their transposition would lead to a worsening of the obliged subject's position, in contrast with the proportionality principle on which is based the compensation statement system. The Italian Supreme Court, by the judgment of 15 April 2015 n. 7283, expresses itself in the opposite direction, stating that “the astreintes provided in other jurisdictions […] are not incompatible with the Italian public policy”. The contemporary Italian law framework, based on the right of “forced execution”, which one can deduct from the art. 24 of the Constitution (which states that all may take legal action for protecting their rights and legitimate interests), is outlined from the Book III, Title IV of the Italian Code of Civil Procedure, indexed “the enforcement of proactive or passive obligations”, Articles 612 to 614 bis c.c.p., where it is possible to involve, from the address of the art. 614 bis c.c.p., the irreplaceable performance, although the same rule has generated several disputes. To underline the value and the transverse projection of the theme, it is proper to highlight the inapplicability of Article 614 bis c.c.p. to individual work disputes listed in art. 409 c.c.p. This exclusion, unjustified and irrational, strongly undermines the principle of equality safeguarded by the art. 3 of the Italian Constitutional Charter, and has given rise to an abundant doctrine that considered art. 614 bis c.c.p., if applied, an extra protection to the right to work contemplated by the art. 4 of the Constitution, and even by art. 18 L. 20 May 1970 n. 300. In this perspective, the art. 614 bis make up a missed opportunity for the code of civil procedure to ensure an executive procedural protection for both parties of the employment contract. The possible reconstructions related to debtor's indirect coercion shows problematic aspects referring to a potential overlap with ordinary protection instruments provided by Articles 1223 c.c., indexed “compensation of the damage”, and 2932 c.c., indexed “specific execution of the obligation to close a contract”, which, for certain doctrine, would be posed after the means provided by art. 614 bis c.c.p. In this way, the executive safeguards to the damage resulting from the breach would be erroneously duplicated. For certain doctrine, this impasse could be overcome by the second paragraph of this Article, with a factual assessment, carried out by the Court, of the abovementioned principle of irreplaceability, excluding its application to all those obligations deprived of such connotation. Some doctrine opposed another configuration, endorsed by the jurisprudence, which postulates a systematic and teleological interpretation, per which it would be possible to extend such protection independently from a postulate of irreplaceability. In this scenario, the research will, at last, offer an interesting train of thought to the debate on legal affairs in the perspective of a possible future and further reform of the civil execution law, also taking into consideration to transpose into Italian Law an institute inspired by punitive damages and based on the penal principle of rehabilitation function of punishment (rectius, in this case, of execution) referred to art. 27 subparagraph 3 of the Italian Constitution

General duality for abelian-group-valued statistical-mechanics models

We introduce a general class of statistical-mechanics models, taking values in an abelian group, which includes examples of both spin and gauge models, both ordered and disordered. The model is described by a set of ``variables'' and a set of ``interactions''. A Gibbs factor is associated to each variable and to each interaction. We introduce a duality transformation for systems in this class. The duality exchanges the abelian group with its dual, the Gibbs factors with their Fourier transforms, and the interactions with the variables. High (low) couplings in the interaction terms are mapped into low (high) couplings in the one-body terms. The idea is that our class of systems extends the one for which the classical procedure 'a la Kramers and Wannier holds, up to include randomness into the pattern of interaction. We introduce and study some physical examples: a random Gaussian Model, a random Potts-like model, and a random variant of discrete scalar QED. We shortly describe the consequence of duality for each example.Comment: 26 pages, 2 Postscript figure

Composite boson dominance in relativistic field theories

We apply a new bosonization technique to relativistic field theories of fermions whose partition function is dominated by bosonic composites, and derive the effective action for these bosons. The derivation respects all symmetries, including gauge invariance, with the exception of Euclidean invariance which must be checked a posteriori. We use a lattice regularization which should make applications to gauge theories easier. We test the method on a fermion field theory with quartic interaction in the limit when the number of flavours N_f is large, and show that it reproduces the exact results in the bosonic sector, namely condensation of a compositeboson with the right mass which breaks the discrete chiral invariance of the model. Moreover we determine the structure function of the condensed composite, whose spatial part turns out to be identical to that of the Cooper pairs of the BCS model of superconductivity

A General Limitation on Monte Carlo Algorithms of Metropolis Type

We prove that for any Monte Carlo algorithm of Metropolis type, the autocorrelation time of a suitable ``energy''-like observable is bounded below by a multiple of the corresponding ``specific heat''. This bound does not depend on whether the proposed moves are local or non-local; it depends only on the distance between the desired probability distribution $\pi$ and the probability distribution $\pi^{(0)}$ for which the proposal matrix satisfies detailed balance. We show, with several examples, that this result is particularly powerful when applied to non-local algorithms.Comment: 8 pages, LaTeX plus subeqnarray.sty (included at end), NYU-TH-93/07/01, IFUP-TH33/9