Non-ergodicity in the Anisotropic Dicke model

We study the ergodic -- non-ergodic transition in a generalized Dicke model with independent co- and counter rotating light-matter coupling terms. By studying level statistics, the average ratio of consecutive level spacings, and the quantum butterfly effect (out-of-time correlation) as a dynamical probe, we show that the ergodic -- non-ergodic transition in the Dicke model is a consequence of the proximity to the integrable limit of the model when one of the couplings is set to zero. This can be interpreted as a hint for the existence of a quantum analogue of the classical Kolmogorov-Arnold-Moser theorem. Besides, we show that there is no intrinsic relation between the ergodic -- non-ergodic transition and the precursors of the normal -- superradiant quantum phase transition.Comment: 5 pages, 4 figure

Book review: analyzing the drone debates: targeted killing, remote warfare, and military technology by James DeShaw Rae

This book aims to examine the principal arguments for and against the use of unmanned aerial vehicles for surveillance and “targeted killing.” Lenneke Sprik finds that the book is a great contribution to the field of military studies, and will be of specific interest to those interested in US foreign and defence policy

Book review: the blood telegram: Nixon, Kissinger and A Forgotten Genocide by Gary J. Bass

Winner of the 2014 Lionel Gelber Prize for Foreign Affairs, The Blood Telegram chronicles how Nixon and Kissinger supported Pakistan’s military dictatorship as it brutally quashed the results of a historic free election. Gary J. Bass argues that the United States’ embrace of the military dictatorship in Islamabad went on to mould Asia’s destiny for decades. This book has the potential to fuel international lawyers to research the legal consequences of the passive stance taken by Nixon and his underlings, writes Lenneke Sprik

Book review: the Yugoslav wars of the 1990s by Catherine Baker

In The Yugoslav Wars of the 1990s, Catherine Baker provides an up-to-date account of the varied interpretations of the origins, causes and consequences of the conflicts. In inviting readers to reconsider a number of assumptions regarding the Yugoslav Wars and indicating where further research is required, this book is an excellent overview that adeptly traverses a wide range of topics, writes Lenneke Sprik

Command Responsibility in Peacekeeping Missions:Normative Obligations of Protection in a Criminal Law Environment

The passive stance taken by respectively Belgian and Dutch peacekeeping commanders towards the commission of genocide in both Kigali (Rwanda) and Srebrenica (Bosnia Herzegovina) has been challenged in domestic courts in recent years. As a result, the individual responsibility of the peacekeeping commanders involved has been addressed. Peacekeeping operations' distinct, normative character combined with the remoteness of peacekeeping troops vis-a-vis the parties to the conflict complicate any legal assessment made regarding the commanders' accountability under international criminal law. This article explores whether a separate type of command responsibility could be developed to fit the specific circumstances in which military commanders operate, based on the command responsibility applied to occupation commanders in post-Second World War trials. Situations of occupation and peacekeeping are characterised by a similar focus on positive rather than negative obligations of protection. Such a normative context may influence how their criminality is perceived. Therefore, this article considers the use of the German Funktionslehre to differentiate between security control and custodial control. That distinction could separate 'peacekeeping command responsibility' from regular command responsibility. Culpability would then be incurred for the failure to act rather than for the crimes committed by a commander's subordinates. Using such a context-sensitive approach to command responsibility for peacekeeping commanders could further a fair assessment of the commander's liability by taking the normative environment in which peacekeeping takes place into account

Chemomechanical equilibrium at the interface between a simple elastic solid and its liquid phase.

Applying diffusion coupled deformation theory, we investigate how the elastic properties of a solid body are modified when forced to keep its chemical potential aligned with that of its melt. The theory is implemented at the classical level of continuum mechanics, treating materials as simple continua defined by uniform constitutive relations. A phase boundary is a sharp dividing surface separating two continua in mechanical and chemical equilibrium. We closely follow the continuum theory of the swelling of elastomers (gels) but now applied to a simple two phase one-component system. The liquid is modeled by a local free energy density defining a chemical potential and hydrostatic pressure as usual. The model is extended to a solid by adding a non-linear shear elastic energy term with an effective modulus depending on density. Imposing chemomechanical equilibrium with the liquid reservoir reduces the bulk modulus of the solid to zero. The shear modulus remains finite. The stability of the hyper-compressible solid is investigated in a thought experiment. A mechanical load is applied to a rectangular bar under the constraint of fixed lateral dimensions. The linear elastic modulus for axial loading is evaluated and found to be larger than zero, implying that the bar, despite the zero bulk modulus, can support a weight placed on its upper surface. The weight is stabilized by the induced shear stress. The density dependence of the shear modulus is found to be a second order effect reducing the density of the stressed solid (chemostriction)