Fast and Succinct Population Protocols for Presburger Arithmetic

In their 2006 seminal paper in Distributed Computing, Angluin et al. present a construction that, given any Presburger predicate as input, outputs a leaderless population protocol that decides the predicate. The protocol for a predicate of size $m$ (when expressed as a Boolean combination of threshold and remainder predicates with coefficients in binary) runs in $\mathcal{O}(m \cdot n^2 \log n)$ expected number of interactions, which is almost optimal in $n$. However, the number of states of the protocol is exponential in $m$. Blondin et al. described in STACS 2020 another construction that produces protocols with a polynomial number of states, but exponential expected number of interactions. We present a construction that produces protocols with $\mathcal{O}(m)$ states that run in expected $\mathcal{O}(m^{7} \cdot n^2)$ interactions, optimal in $n$, for all inputs of size $\Omega(m)$. For this we introduce population computers, a carefully crafted generalization of population protocols easier to program, and show that our computers for Presburger predicates can be translated into fast and succinct population protocols.Comment: 52 pages, 4 figures, to be published in SAND 202

Enhancing 'Human Nature': The Human Enhancement Debate in U.S. Bioethics

It is often remarked that we are entering into a biotech age that will afford us with the unprecedented means to remake human biology. The question is: should we use our imminent techno-scientific powers to ‘enhance’ and even ‘transcend’ our ‘natural’ limitations or remain human ‘as we have always been’? But is this the right question? This dissertation critically examines the human enhancement debate in bioethics and bioethics-adjacent literature. More specifically, it mobilizes a wide range of disciplinary tools to reflexively explore the discursive resonances, effects, and shortcomings of human enhancement as a conceptual framework. Through this exploration, I demonstrate that the well-established therapy/enhancement distinction depends upon deeply humanist ontologies that are insufficient for understanding and addressing the biotechnological ‘crisis’. In turn, I provide a posthumanist approach to thinking human nature, which highlights the relational, embodied, and differential character of subjectivity. Such an approach implies that we have always been cyborgs and, therefore, never been human as such. In doing so, I take a small step towards constructing post-enhancement frameworks for doing bioethics in our posthuman moment

Balance of Threat, Balance of Mind: Nuclear Rivalry and Arms Control

Under what conditions will rivals choose to accept mutual constraints, limitations, and even reductions on their capabilities for waging war? Contemporary political science lacks a strong theoretical basis for understanding this behavior, despite the fact that states in the modern era continue to negotiate and enter into arms control arrangements. This study contributes a theoretical framework and empirical analysis identifying the conditions under which nuclear-armed rivals might choose to curb their deadly arsenals. Traditional theories grounded in classical deterrence theory suggest arms control serves to preserve a deterrent status quo and prevent expensive and destabilizing arms competition; it should therefore only be expected when rivals feel secure in the strength and effectiveness of their respective retaliatory capabilities. This study suggests a more complicated (yet still predictive) causal logic in which this balance of force is dynamically interactive with militarized hostility and rivals convergence or divergence in how they think — both normatively and instrumentally — about the role of nuclear weapons in their national security. The argument is illustrated through qualitative comparative analysis (QCA) of bilateral arms control interactions among nuclear-armed strategic rivals from 1949 to the present. Further analysis is provided through in-depth case studies of arms control dynamics between three pairs of contemporary nuclear rivals — the United States and Russia, India and Pakistan, and the United States and China

Towards a Peaceful Development of Cyberspace - Challenges and Technical Measures for the De-escalation of State-led Cyberconflicts and Arms Control of Cyberweapons

Cyberspace, already a few decades old, has become a matter of course for most of us, part of our everyday life. At the same time, this space and the global infrastructure behind it are essential for our civilizations, the economy and administration, and thus an essential expression and lifeline of a globalized world. However, these developments also create vulnerabilities and thus, cyberspace is increasingly developing into an intelligence and military operational area – for the defense and security of states but also as a component of offensive military planning, visible in the creation of military cyber-departments and the integration of cyberspace into states' security and defense strategies. In order to contain and regulate the conflict and escalation potential of technology used by military forces, over the last decades, a complex tool set of transparency, de-escalation and arms control measures has been developed and proof-tested. Unfortunately, many of these established measures do not work for cyberspace due to its specific technical characteristics. Even more, the concept of what constitutes a weapon – an essential requirement for regulation – starts to blur for this domain. Against this background, this thesis aims to answer how measures for the de-escalation of state-led conflicts in cyberspace and arms control of cyberweapons can be developed. In order to answer this question, the dissertation takes a specifically technical perspective on these problems and the underlying political challenges of state behavior and international humanitarian law in cyberspace to identify starting points for technical measures of transparency, arms control and verification. Based on this approach of adopting already existing technical measures from other fields of computer science, the thesis will provide proof of concepts approaches for some mentioned challenges like a classification system for cyberweapons that is based on technical measurable features, an approach for the mutual reduction of vulnerability stockpiles and an approach to plausibly assure the non-involvement in a cyberconflict as a measure for de-escalation. All these initial approaches and the questions of how and by which measures arms control and conflict reduction can work for cyberspace are still quite new and subject to not too many debates. Indeed, the approach of deliberately self-restricting the capabilities of technology in order to serve a bigger goal, like the reduction of its destructive usage, is yet not very common for the engineering thinking of computer science. Therefore, this dissertation also aims to provide some impulses regarding the responsibility and creative options of computer science with a view to the peaceful development and use of cyberspace

Human Security and Sustainable Development in East Africa

This book investigates contemporary human security issues in East Africa, setting forth policy recommendations and a research agenda for future studies. Human security takes a people-centered rather than state-centered approach to security issues, focusing on whether people feel safe, free from fear, want and indignity. This book investigates human security in East Africa, encompassing issues as diverse as migration, housing, climate change, displacement, food security, aflatoxins, land rights, and peace and conflict resolution. In particular, the book showcases innovative original research from African scholars based on the continent and abroad, and together the contributors provide policy recommendations and set forth a human security research agenda for East Africa, which encompasses Kenya, Uganda, Tanzania, Somalia, Rwanda, Burundi, South Sudan, Sudan, Ethiopia, Eritrea, and Djibouti. As well as being useful for policy makers and practitioners, this book will interest researchers across African Studies, Security Studies, Environmental Studies, Political Science, Global Governance, International Relations, and Human Geography