Some non perturbative calculations on spin glasses

Models of spin glasses are studied with a phase transition discontinuous in the Parisi order parameter. It is assumed that the leading order corrections to the thermodynamic limit of the high temperature free energy are due to the existence of a metastable saddle point in the replica formalism. An ansatz is made on the form of the metastable point and its contribution to the free energy is calculated. The Random Energy Model is considered along with the p-spin and the p-state Potts Models in their p < infinity expansion.Comment: 12 pages, LaTe

Primordial Entropy Production and Lambda-driven Inflation from Quantum Einstein Gravity

We review recent work on renormalization group (RG) improved cosmologies based upon a RG trajectory of Quantum Einstein Gravity (QEG) with realistic parameter values. In particular we argue that QEG effects can account for the entire entropy of the present Universe in the massless sector and give rise to a phase of inflationary expansion. This phase is a pure quantum effect and requires no classical inflaton field.Comment: 12 pages, 4 figures, IGCG-07 Pun

Kondo effect in a one dimensional d-wave superconductor

We derive a solvable resonant-level type model, to describe an impurity spin coupled to zero-energy bound states localized at the edge of a one dimensional d-wave superconductor. This results in a two-channel Kondo effect with a quite unusual low-temperature thermodynamics. For instance, the local impurity susceptibility yields a finite maximum at zero temperature (but no logarithmic-divergence) due to the splitting of the impurity in two Majorana fermions. Moreover, we make comparisons with the Kondo effect occurring in a two dimensional d-wave superconductor.Comment: 9 pages, final version; To be published in Europhysics Letter

Mitigating humanitarian crises during non-international armed conflicts:the role of human rights and ceasefire agreements

Situations of humanitarian crisis are often caused by armed conflicts. Given the prevalence of non-international armed conflicts today, ways of ameliorating these situations are at the forefront of concerns. The international humanitarian law rules governing non-international armed conflict remain much less developed than those for international armed conflicts. This is exacerbated by the lack of direct human rights obligations for non-state armed groups, which makes governing the behaviour of non-state parties to non-international armed conflicts (non-state armed groups) even more challenging. Although several initiatives have been taken to encourage non-state actors to mitigate situations of humanitarian crisis, the role of human rights law is in need of further clarification. The paper aims to assess what role human rights may have in improving humanitarian crises, suggesting one specific way: The paper will first discuss the international laws applicable to situations of non-international armed conflict, before critically analysing some of the initiatives that have already been taken to govern the behaviour of non-state armed groups. Part 3 will assess the possibility of using cease-fire agreements to impose specific human rights obligations on all parties to a non-international armed conflict. Finally, a conclusion will be drawn in Part 4 as to the role that human rights and ceasefire agreements could have during humanitarian crises