Publikationer från Stockholms universitet
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Modeling RABITT phases in relativistic regions of heavy atoms
No full textThe study of electron dynamics in photoionization has long been, and continues to be, a major scientific frontier. Due to the ultrafast nature of electron-related processes — occurring on the attosecond timescale — their detailed investigation has only become feasible in recent decades. Advances in attosecond science, particularly High Harmonic Generation (HHG), have provided the necessary temporal resolution to explore such phenomena with high precision. Since electrons are described by complex wavefunctions, a complete characterization involves measuring not only the wave amplitudes but also their phases, which often hold crucial information about the underlying physical process. For instance, during photoionization, freed electrons experience a phase shift due to the many-body potential of the parent ion, which can also be understood as an ionization delay. The above-mentioned phase shift (or delay) can be measured using so-called pump-probe experiments, where an electron wave packet, ionized by an extreme ultraviolet (XUV) pulse of the attosecond duration (the ”pump”), is analyzed with a second (”probe”) pulse, often in the infrared (IR) range. A well-known example of such experiments is Reconstruction of Attosecond Beatings by Interference of Two-Photon Transitions (RABITT). In multi-electron systems, accurately modeling RABITT experiments requires advanced theoretical techniques that account for electron correlation. The Random Phase Approximation with Exchange (RPAE) method is an effective approach, applicable to both non-relativistic and, using Relativistic RPAE (RRPAE), relativistic systems. These models are especially crucial near atomic resonances, where complex electron-electron interactions must be captured. In RABITT measurements, such resonances manifest as abrupt phase shifts, which depend on the resonance’s shape and magnitude and may vary with the emission angle of the photoelectron. This thesis employs RRPAE to model RABITT experiments in radon, a heavy atom where relativistic effects — such as the pronounced 6p3/2 – 6p1/2 fine-structure splitting — are clearly evident. Special attention is given to analyzing photoionization phase shifts and their dependence on the emission angle near autoionizing resonances between radon’s first (6p3/2) and second (6p1/2) ionization thresholds. Additionally, an analytical model is developed to predict the shapes and energy positions of these resonant phase shifts
Gender and Reality in A Voyage to Arcturus
No full textIn his debut novel A Voyage to Arcturus (1920) David Lindsay presents a grim and unforgiving vision of the tangible world as steeped in falsity. Physical reality is an illusion that must be overcome. At the centre of this illusion, the body and its sexed state are represented as particularly precarious. As Maskull, a man from Earth, travels across the planet Tormance, his Promethean quest provides a background for metaphysical speculations, where bodies and sexes are problematised in a manner that anticipates queer theoretical discussions and feminist science fiction. In the present thesis I provide a queer reading of some of the many scenes in the novel where these speculations can be discerned. I do not claim that Lindsay is a queer or feminist writer but rather that the problems he has with these issues reflect the arbitrariness and instability of gendered identity. Although he could not benefit from the kinds of gender analysis that have emerged within the last decades, I have nonetheless found it fruitful to apply recent theories, especially the work of Judith Butler, to a close reading of relevant passages in the novel. I argue that David Lindsay, for all his late Victorian puritanism and his anxious relationship to women and sexuality, can be read as a precursor of sorts to queer theorists like Butler, and that he broaches subjects that later become important in feminist science fiction
ChatGPT as a Playwrighter in the Theatre Classroom : A Case Study on Generative AI within theatre education at upper secondary school level
No full textThis study explores the integration of generative AI, specifically ChatGPT, as a co-creator in playwriting within upper secondary theatre education. Conducted as an exploratory case study within a postqualitative framework, the research investigates how students and teachers engage with AI in the creative writing processes of theatre classes. Data were collected through a workshop with first-year theatre students, followed by a focus group and interviews with theatre teachers. Using diffractive analysis, the findings reveal both possibilities and limitations. Participants found ChatGPT useful for generating ideas and overcoming writer’s block. However, they also noted a lack of emotional depth, embodied nuance, and contextual awareness in its output – qualities essential to effective playwriting. A key tension emerged between the efficiency and fluency offered by AI and the collaborative, sensory-rich processes that characterize theatrical creativity. This study contributes to ongoing discussions about AI in arts education by highlighting the need for thoughtful pedagogical strategies. While generative AI can serve as a supplementary tool in scriptwriting, its integration must be carefully considered to preserve the human elements of collaboration, interpretation, and embodied expression that define theatre education.Denna studie undersöker hur generativ artificiell intelligens, specifikt ChatGPT, kan användas som medskapare när gymnasielever skriver teatermanus. Studien genomfördes som en explorativ fallstudie med postkvalitativ metodologi och utforskade hur elever och lärare samspelar med AI i det kreativa skrivandet. Data samlades in genom en workshop med förstaårselever på teaterprogrammet, följt av fokusgrupp och intervjuer med teaterlärare. Genom diffraktiv analys visar resultaten både möjligheter och begränsningar. Deltagarna upplevde ChatGPT som användbart för att få fram idéer och komma igång med skrivandet. Samtidigt saknade AI:s texter emotionellt djup, känslomässiga nyanser och förståelse för sammanhang – kvaliteter som är avgörande för bra dramatik. En central spänning framträdde mellan den effektivitet och flyt som AI erbjuder och de samarbetsinriktade, kroppsliga processer som kännetecknar teaterskapande.Studien bidrar till pågående diskussioner om AI i konstutbildning genom att belysa behovet av genomtänkta pedagogiska strategier som erkänner både AI:s möjligheter och dess begränsningar utan att förlora kontakten med teaterns mänskliga kärna
(Un)bounded imaginaries : Urban transformation pathways towards a safe and just future in Monterrey, Mexico
No full textHumanity faces unprecedented social-ecological challenges. The Earth System Boundaries (ESB) framework proposes that it is possible to live a within a safe and just space, where earth system functions are maintained while ensuring minimum access to resources for all. But what this safe and just future entails and how to achieve it remains uncertain. This study explores alternative futures for Monterrey, Mexico through participatory futures-thinking methodologies. Engaging a diverse group of local stakeholders, we co-created a local ESB model, and then explored visions and transformation pathways to achieve a future within these locally identified ESB. Three distinct visions emerged, reconceptualizing the city’s relationship between nature and society, and each with unique pathway dynamics. Achieving these visions calls for cultural, economic and social paradigm shifts, and the pathways highlighted two theories of change that converge in the creation of these alternative futures. The pathways also underscored the fragility of transformation, trade-offs across boundaries and scales, and the need to address systemic inequalities to achieve transformative change. This research contributes to global sustainability efforts by bridging the global ESB framework with local narratives, offering concrete avenues for change for Monterrey while challenging the assumptions that guide global scenario-making processes. The findings underscore the importance of pluralistic, bottom-up approaches to envision and materialize sustainable futures. La humanidad enfrenta desafíos socio-ecológicos sin precedentes. El marco de los Límites del Sistema Tierra (ESB por sus siglas en inglés) propone que es posible vivir en un espacio seguro y justo, donde se mantengan las funciones del sistema terrestre y al mismo tiempo se garantice un acceso mínimo a recursos a todas las personas. Pero qué implica este futuro seguro y justo y cómo lograrlo sigue siendo incierto. Este estudio explora futuros alternativos para Monterrey, México, usando metodologías participativas de pensamiento de futuros (futures- thinking). Con la participación de un grupo diverso de actores locales, cocreamos un modelo local de los ESB, y posteriormente exploramos visiones y trayectorias de transformación para lograr un futuro dentro de estos ESB locales. Surgieron tres visiones distintas que reconceptualizan la relación entre la naturaleza y la sociedad dentro de la ciudad, cada una con dinámicas de trayectorias únicas. Lograr estas visiones requiere cambios de paradigma culturales, económicos y sociales, y las trayectorias destacaron dos teorías de cambio que convergen en la creación de estos futuros alternativos. Las trayectorias también subrayaron la fragilidad de los procesos de transformación, los compromisos entre límites y escalas, y la necesidad de abordar las desigualdades sistémicas para lograr un cambio transformador. Esta investigación contribuye a los esfuerzos global de sustentabilidad al conectar el marco global de ESB con narrativas locales, ofreciendo vías concretas de cambio para Monterrey a la vez que se cuestionan los supuestos que guían los procesos de elaboración de escenarios globales. Los hallazgos subrayan la importancia de integrar enfoques plurales y hacer énfasis en procesos que partan desde la participación comunitaria para visualizar y materializar futuros sustentables.
”Förstår du inte att det är en psykopat du har att göra med?” : En kvalitativ analys av medias framställning av gärningspersoner med utländsk respektive svensk etnicitet som är dömda för mord.
No full textLLM-Powered NPC Agents
No full textNon-Playing Characters (NPCs) are fundamental to video games, taking on the role of each character not played by any human that inhabits the game world. Instead they’re actions and behaviours are controlled by the game’s computer system. However, a persistent challenge in NPC design is achieving believability, ensuring that NPCs meet players’ expectations in the roles they’re meant to portray. Traditional NPC behaviors, interactions, and dialogues have relied on scripted content, which, despite advancements, remains inherently rigid. The recent breakthroughs in the field of artificial intelligence (AI), particularly large language models (LLMs), presents an opportunity to overcome some limitations, especially in the realm of NPCs’ social interactions with the player. LLMs can dynamically generate contextually appropriate dialogue and behaviors, which may greatly enhance the NPCs believability as well as aligning with the principles of emergent narrative, an approach in Game Design that describes the occurrence of character-driven storytelling over embedded narratives which are the plots already put in place by the developers. While emergent narrative offers compelling possibilities, it also introduces challenges, such as distinguishing meaningful events from mundane or contradictory occurrences and effectively presenting dynamic stories in real-time. This study examines the potential of LLM-powered NPCs in addressing these challenges, particularly in enhancing believability and emergent storytelling. By integrating LLMs into NPC design, this research aims to evaluate and compare their impact on player experience and interactive storytelling, juxtaposed to scripted NPCs, providing insights into the future of AI-integrated video games. Eight participants with prior experience of interacting with traditional NPCs in role-playing games (RPGs) such as Skyrim, were recruited for this study. Each participant underwent an initial structured interview, followed by the case study which had them interacting with LLM-powered NPCs in the RPG Skyrim using the Mantella Mod, a modification for Skyrim which allows for LLM integration. Lastly, a final semi-structured interview was held after the case study. With the use of a Thematic Analysis, the data collected from the interviews and gameplay recordings showed that use of LLM-powered NPCs have various impacts on NPC design and were identified and categorized in four distinct themes; “Immersion & Believability,” “Narrative Emergence,” “Comparative Perception” and “Technical & Design Constraints”. The results showed that the participants experienced a greater sense of immersion by communicating with LLM-powered NPCs as it felt more natural and unrestricted. However, the findings also indicated that this technology is not without its current technical flaws, and by mitigating the problem of restricted dialogue trees of traditional NPC design, it introduces new problems which relates to the player’s real life communication skills or the lack thereof. Moreover, the freedom provided by the usage of LLMs may not be easily implemented in a game with embedded narratives as they are in direct contradiction with each other
Humanitarian Aid in Northern Syria: Challenges, Adaptations,and Complexities : An Analysis of OCHA's Aid Delivery after the 2023 earthquake in Idlib Governorate
No full textThe Syrian Revolution, which began on 15 March 2011, has resulted in a prolonged and multifaceted crisis, particularly in northern regions outside the control of the Syrian state until the fall of the Assad regime on 8 December 2024. This precarious situation was further exacerbated on 6 February 2023, when a 7.7-magnitude earthquake struck northwest Syria, intensifying an already critical humanitarian emergency. Contributing factors include the ongoing international embargo, the presence of non-state armed groups (NSAGs), fragile infrastructure, and the persistent conflict between the Syrian government and NSAGs. This thesis employs Robert M. Entman’s framing theory to examine how the United Nations Office for the Coordination of Humanitarian Affairs (OCHA) framed the humanitarian challenges in the Idlib governorate after the 2023 earthquake. The analysis focuses on three core framing functions: problem definition, causal interpretation, and moral judgment. It is argued that OCHA’s framing played a significant role in shaping how the humanitarian crisis was understood and prioritised in international discourse. To critically assess the implications of this framing, the thesis also investigates the operational and ethical challenges that OCHA encountered while attempting to deliver aid in northwest Syria. While formally upholding the core humanitarian principles of neutrality, impartiality, and independence, the study finds that the actual delivery of aid was constrained by political, security, and structural factors. These constraints reveal a tension between OCHA's normative commitments and the complex realities of humanitarian governance in conflict-affected regions. This subject remains particularly relevant in light of the continuing humanitarian crises in regions such as Gaza, Sudan, and the Democratic Republic of the Congo (DRC), the persistent challenges confronting humanitarian actors in protracted conflicts, and the broader debate surrounding the politicisation of aid and the ethical tensions inherent in upholding humanitarian principles under such complex conditions
The Impact of Political Institutions on Climate Policy Effectiveness : Cross-National Evidence from Two Decades
No full textDespite the rise in national climate policies, current efforts remain inadequate to prevent the adverse effects of climate change. Evidence shows that only a small fraction of policies enacted over the past two decades have resulted in measurable emission reductions, underscoring the need to better understand what drives climate policy effectiveness. This study explores how political institutions shape the effectiveness of national climate policies, defined as the extent to which policies lead to reduced emissions. Analyzing over 1,000 mitigation policies across 41 countries from 1997 to 2021, the study applies recent advances in causal policy attribution to link institutional features to policy outcomes. Results from fixed and mixed effects regression models reveal that both higher levels of democracy and stronger government power are positively associated with policy effectiveness. While democracy correlates with a greater number of effective policies, it does not increase their proportion. In contrast, stronger government power increases both the number and share of effective policies. No significant effects are found for government ideology or corruption. These findings highlight the critical role of institutional context, especially democracy and government power, in enhancing climate policy outcomes
Nytt årtionde, samma approach : En studie av New Decade, New Approach-avtalets tillkomst i Nordirland
No full textThis study aimed to examine the process that led to the emergence of the peace agreement New Decade, New Approach (NDNA), trace its development, and analyse it through the lens of historical institutionalism. NDNA is the latest of the eight (8th) agreements in the seemingly perpetual peace process of Northern Ireland and by studying the process on how it was negotiated we may gleam important knowledge about the state of current political actors in the ongoing peace process and their core issues. The process around NDNA was defined by its lack of progress and the unwillingness of the political actors to compromise, despite significant consequences for the citizens of Northern Ireland. By using theory testing process-tracing methods this study shows that the political actors of Northern Ireland and the surrounding negotiation institutions was influenced by earlier policy decisions and institutional structures in a way that hinders developments. Despite being essentially in agreement, the process took three years due to the inability to change positions once taken. The theories of path dependency and critical junctures explains to a degree why the process developed as it did and is supported by the findings of this study