Light scattering and dissipative dynamics of many fermionic atoms in an optical lattice

We investigate the many-body dissipative dynamics of fermionic atoms in an optical lattice in the presence of incoherent light scattering. Deriving and solving a master equation to describe this process microscopically for many particles, we observe contrasting behaviour in terms of the robustness against this type of heating for different many-body states. In particular, we find that the magnetic correlations exhibited by a two-component gas in the Mott insulating phase should be particularly robust against decoherence from light scattering, because the decoherence in the lowest band is suppressed by a larger factor than the timescales for effective superexchange interactions that drive coherent dynamics. Furthermore, the derived formalism naturally generalizes to analogous states with SU(N) symmetry. In contrast, for typical atomic and laser parameters, two-particle correlation functions describing bound dimers for strong attractive interactions exhibit superradiant effects due to the indistinguishability of off-resonant photons scattered by atoms in different internal states. This leads to rapid decay of correlations describing off-diagonal long-range order for these states. Our predictions should be directly measurable in ongoing experiments, providing a basis for characterising and controlling heating processes in quantum simulation with fermions.Comment: 18 pages, 7 figure

Theorizing refugeedom: Becoming young political subjects in Beirut

Arek Dakessian - ORCID 0000-0001-7792-6862 https://orcid.org/0000-0001-7792-6862Refugees can be formed as “subjects” as they navigate forced displacement in countries that are not their own. In particular, everyday life as the politicized Other, and as humanitarianism’s depoliticized beneficiary, can constitute them as political subjects. Understanding these produced subjects and subjectivities leads us to conceive of forced displacement – or “refugeedom” – as a human condition or experience of political (sub)alterity, within which inhere distinctive subjectivations and subjectivities. Drawing on fieldwork in Beirut, Lebanon, we use young Syrian and Iraqi refugees’ experiences with everyday racism, violent bullying and racialized discrimination as heuristic lenses with which to see displacement’s political subjects and subjectivities. We argue that the young refugees emerge as both political and moral subjects through core and defining struggles within – and against – these politicizing constraints. We interpret their struggles as ambivalently and dynamically situated within humanitarianism’s and racism’s subjections and subjectivities. Yet we also found that occasionally the young refugees could eclipse these produced subjectivities to claim repoliticized subjecthoods distinct from those of humanitarianism and outside displacement’s normal politics. We interpret these in Rancièrian terms as “political subjectivation.” Abstracting our findings, we offer a simple theoretical architecture of refugeedom’s subjectivations, subjects, and subjectivities as comprising humanitarianism’s rights-bearing or juridical subject; the vulnerable and resilient, innocent and suffering subject; and the Othered or racialized subject, formed through the exclusions of displacement’s politicized spaces. But we also conceive refugeedom as a space of values, and so the ground on which moral meaning and significance attach to agency and subjectivity.Fieldwork was funded by The British Academy (Academic Grant Number SG152525).https://doi.org/10.1007/s11186-020-09393-249pubpu

The responsibility to protect and the case of Darfur

Die vorliegende Diplomarbeit untersucht das Konzept der “Schutzverantwortung” (R2P) anhand der Fallstudie Darfur. Um das so genannte Interventionsdilemma der 1990er Jahre zu überwinden, sollte ein Wechsel vom “Recht zur Intervention” zur “Schutzverantwortung” bewirkt werden. Dabei spielt der Paradigmenwechsel im Sicherheitsverständnis hin zum Konzept der „menschlichen Sicherheit“ nach dem Kalten Krieg eine entscheidende Rolle. Diese Arbeit zeichnet die Entwicklung von R2P nach und beleuchtet kritisch die Kerninhalte der Schutzverantwortung. Wie das Beispiel Darfur zeigt, ist das Konzept R2P noch zu schwach in der internationalen Staatengemeinschaft verankert. Es gibt zwar das Lippenbekenntnis, Gräueltaten Einhalt zu gebieten, tatsächlich sind aber nationales Interesse und staatliche Souveränität noch stark ausgeprägt. Ein wichtiger Faktor ist dabei das Versagen des mächtigsten UN-Organs, dem Sicherheitsrat, Verbrechen gegen die Menschlichkeit oder Genozid zu verhindern. Um künftige Verbrechen wie jene in Ruanda, Bosnien oder Darfur verhindern zu können, muss R2P auf eine neue Grundlage gesetzt werden und sich stärker an die Überlegungen der International Commission on Intervention and State Security orientieren.The present thesis assesses the concept of the ‘responsibility to protect’ (R2P) based on the case study of the Darfur conflict. R2P was introduced to overcome the ‘dilemma of intervention’ of the 1990s, to shift the terms of the debate from the ‘right to intervene’ to the ‘responsibility to protect.’ The paradigm change from a traditional understanding of security towards the concept of human security played a crucial role. This thesis examines the development of R2P and critically reflects on the substance of R2P. The Darfur crisis illustrates that the R2P concept is entrenched too weakly in the international community. Lip service is often paid to the will of halting mass atrocities, yet national interest and state sovereignty proves to be stronger. An important factor is the failure of the most powerful UN body, the Security Council, to prevent crimes against humanity or genocide. To avert crimes like those in Rwanda, Bosnia or Darfur in the future, R2P has to renew its basis and has to refer back to the 2001 recommendations of the International Commission on Intervention and State Security again

Inclusión y exclusión de la sociedad civil en la comisión de la verdad de Timor Oriental

Truth commissions are a key part of transitional justice measures that allow clarifying the past related to oppression during dictatorship or the horrors of armed conflict. It is civil society that often plays an important role in promoting and pushing the mandate of a truth commission, ensuring transparent work and a widespread distribution of the final report and the implementation of its recommendations. In Timor Leste, the Commission for Reception, Truth and Reconciliation (CAVR) was a United Nations–led initiative, implemented after the 1999 violence around the independence referendum from Indonesia. Civil society had a limited role to play in the work of the CAVR, not least because the truth commission was not perceived to be an instrument that brings about justice, the main demand of the community. The CAVR shows that without pressure of local civil society, truth commissions will hardly leave an impact.Las comisiones de la verdad son parte clave de las medidas de justicia transicional que permiten esclarecer el pasado durante dictaduras o conflictos armados. La sociedad civil a menudo desempeña un importante papel en la promoción e implementación del mandato de una comisión de la verdad, garantizando así la transparencia en el trabajo, una amplia distribución del informe final y la aplicación de sus recomendaciones. En Timor Leste, la Comisión de Acogida, Verdad y Reconciliación (CAVR) fue una iniciativa de las Naciones Unidas implementada después de la violencia de 1999, relacionada con el referéndum de independencia de Indonesia. La sociedad civil tuvo un papel limitado en el trabajo de la CAVR puesto que ésta no fue percibida como una herramienta de justicia, lo cual era la principal demanda de la comunidad. La CAVR pone en evidencia que las comisiones de la verdad, sin la presencia de la sociedad civil, difícilmente tienen algún impacto

Current discourses on the Holocaust in Lithuania

In Litauens kollektivem Gedächtnis sind zwei Narrative über den Holocaust in Litauen auszumachen. Litauer sehen sich vor allem als Opfer des Zweiten Weltkriegs, besonders während der stalinistischen Okkupation. Im Gegensatz dazu steht die jüdische Erinnerung weil während der Nazi-Besatzung de facto das litauische Judentum vernichtet wurde. Obwohl die Deutschen den Holocaust organisiert und implementiert hatten, waren sie auf die lokale Kollaboration von Litauern angewiesen um den Massenmord an etwa 200,000 litauischen Juden so rasch und gründlich durchzuführen. In Litauens Elite wird seit Mitte der 1990er eingestanden, dass Litauer am Holocaust beteiligt waren. Es wird aber kein selbstkritischer Diskurs über dieses dunkle Kapitel der Vergangenheit geführt sondern vielmehr wird versucht die eigenen Landsleute reinzuwaschen. Eine der größten Herausforderungen ist der Umstand, dass der jüdische Genozid nicht als Teil der litauischen Geschichte wahrgenommen wird: Es wurden Juden und nicht Litauer emordet. Obwohl Juden die litauische Staatsbürgerschaft inne hatten wurden sie als Außenstehende und nicht als Einheimische betrachtet. Das kollektive Gedächtnis in Litauen ist vor allem von der Generation der Großeltern geprägt die den Zweiten Weltkrieg durchgemacht hatten. Daher wird die kollektive Erinnerung an den Holocaust in Litauen kaum durch Institutionen sondern vor allem im persönlichen Raum geformt. Bis heute ist eine kritische Auseinandersetzung mit dem Holocaust in Litauen im Land selbst kaum anzutreffen und auch in näherer Zukunft ist nicht davon auszugehen, dass sich daran etwas ändert.Two competing narratives exist in LithuaniaPs collective memory of the Holocaust in Lithuania. Lithuanians follow largely a narrative that presents themselves as the victim of WWII, particularly during the Stalinist occupation. This line is in strong contrast to the Jewish memory because about 95% of LithuaniaPs Jewry was wiped out during the Nazi occupation. Although it were the Germans who organized and implemented the Holocaust, without the local collaboration in Lithuania the mass killings of some 200,000 Jews could not have taken place that quickly and thoroughly. LithuaniaPs elite has recognized since the mid-1990s that Lithuanians took part in the Holocaust. Instead of a self-critical discourse about the past, it is preferred to whitewash their compatriots. The main challenge is that the Jewish genocide is not recognized as part of LithuaniaPs history. It is „them,7 the Jews, who were killed and not Lithuanians. Although they were Lithuanian citizens it seems that they were aliens and not natives to the country. The collective memory on WWII itself is mainly shaped by the grandparents who eventually had lived through WWII. Thus, collective memory of the Holocaust in Lithuania is hardly created by institutions but is rather found in the personal space. A collective memory of the Holocaust in Lithuania which critically reflects the past will remain an alien narrative to Lithuanians, most likely also in the near future

Explanatory machine learning for sequential human teaching

The topic of comprehensibility of machine-learned theories has recently drawn increasing attention. Inductive Logic Programming (ILP) uses logic programming to derive logic theories from small data based on abduction and induction techniques. Learned theories are represented in the form of rules as declarative descriptions of obtained knowledge. In earlier work, the authors provided the first evidence of a measurable increase in human comprehension based on machine-learned logic rules for simple classification tasks. In a later study, it was found that the presentation of machine-learned explanations to humans can produce both beneficial and harmful effects in the context of game learning. We continue our investigation of comprehensibility by examining the effects of the ordering of concept presentations on human comprehension. In this work, we examine the explanatory effects of curriculum order and the presence of machine-learned explanations for sequential problem-solving. We show that 1) there exist tasks A and B such that learning A before B has a better human comprehension with respect to learning B before A and 2) there exist tasks A and B such that the presence of explanations when learning A contributes to improved human comprehension when subsequently learning B. We propose a framework for the effects of sequential teaching on comprehension based on an existing definition of comprehensibility and provide evidence for support from data collected in human trials. Empirical results show that sequential teaching of concepts with increasing complexity a) has a beneficial effect on human comprehension and b) leads to human re-discovery of divide-and-conquer problem-solving strategies, and c) studying machine-learned explanations allows adaptations of human problem-solving strategy with better performance.Comment: Submitted to the International Joint Conference on Learning & Reasoning (IJCLR) 202

Digital Education Policies in Europe and Beyond: Key Design Principles for More Effective Policies

This report offers policy-makers in digital education evidence on how, at the national or regional level, policies can be designed and implemented to foster digital-age learning. The presented findings are the result of a mixed methodological design comprising four parts: desk-research on digital education policy, the identification of national and regional policies worldwide, six in-depth case studies, and an expert workshop. The discussion of the cases identified and studied in depth leads to the formulation of eight core-guiding principles, which can serve as a reference point for policy-makers for the design and implementation of digital education policies: 1. Follow a holistic approach targeting systemic change; 2. Establish both a long-term vision and short-term achievable goals; 3. Deploy technology as a means not an end; 4. Embrace experimentation, risk-taking and failure; 5. Consider the importance and the limits of impact assessment; 6. Involve all stakeholders in a structured dialogue; 7. Let schools and teachers have a say; 8. Build up teaching competence.JRC.B.4-Human Capital and Employmen