Chaotic attractors with the symmetry of a tetrahedron

International audienceFunctions that are equivariant with respect to the symmetries of a tetrahedron are determined. Linear combinations of these functions that give rise to chaotic attractors are used to create images in 3-space of attractors with the symmetry of the tetrahedron. These attractors are visually appealing because of the tension between the pattern forced by their symmetry and the randomness arising from their chaotic behavior

The Future of Aztec Law

This article models a methodology for recovering the substance and nature of the Aztec legal tradition by interrogating reports of precontact indigenous behavior in the works of early colonial ethnographers, as well as in pictorial manuscripts and their accompanying oral performances. It calls for a new, richly recontextualized approach to the study of a medieval civilization whose sophisticated legal and jurisprudential practices have been fundamentally obscured by a long process of decontextualization and the anachronistic applications of modern Western paradigms

Multi-temporality and pitch permutations: Creating networks of time and tone as raw material for composition

The following commentaries will examine my recent music from both technical and aesthetic viewpoints, focusing in particular on my exploration of both harmonic permutation fields and polyrhythmic space, and the various ways in which these have been used to create harmonic/temporal networks as raw material for composition. Whilst investigating the development and subsequent interactions of these two techniques, the commentary will also consider how this approach has evolved organically from the desire to create pre-compositional material which is both flexible and simple to define, but which also has the potential for diverse compositional outcomes, providing the composer a rich seam of material to work during the compositional process. In the interest of clarity, we will consider the harmonic and temporal aspects of my approach separately in sections 2.0 and 2.1, respectively, leaving section 2.2 to outline a more unified conception of working methods which have resulted from this research, building on the ideas presented previously

Memory-induced complex contagion in spreading phenomena on networks

[eng] Epidemic modeling has proven to be an essential framework for the study of contagion phenomena in biological, social, and technical systems. Albeit epidemic models have evolved into powerful predictive tools, most assume memoryless agents and independent transmission channels. Nevertheless, many real-life examples are manifestly time-sensitive and show strong correlations. Moreover, recent trends in agent-based modeling support a generalized shift from edge-based descriptions toward node-centric approaches. Here I develop an infection mechanism that is endowed with memory of past exposures and simultaneously incorporates the joint effect of multiple infectious sources. A notion of social reinforcement/inhibition arises organically, without being incorporated explicitly into the model. As a result, the concepts of non-Markovian dynamics and complex contagion become intrinsically coupled. I derive mean-field approximations for random degree-regular networks and perform extensive stochastic simulations for nonhomogeneous networks. The analysis of the SIS model reveals a sophisticated interplay between two memory modes, displayed by a collective memory loss and the dislocation of the critical point into two phase transitions. An intermediate region emerges where the system is either excitable or bistable, exhibiting fundamentally distinct behaviors compared to the customary healthy and endemic phases. Additionally, the transition to the endemic phase becomes hybrid, showing both continuous and discontinuous properties. These results provide renewed insights on the interaction between microscopic mechanisms and topological aspects of the underlying contact networks, and their joint effect on the properties of spreading processes. In particular, this type of modeling approach that combines memory effects and complex contagion could be suitable to describe ecological interactions between biological and social pathogens.[cat] El modelatge epidèmic ha demostrat ser un marc essencial per a l’estudi dels fenòmens de contagi en sistemes biològics, socials i tècnics. Tot i que els models epidèmics han evolucionat cap a potents eines de predicció, la majoria assumeixen agents sense memòria i canals de transmissió independents. No obstant això, molts exemples de la vida real mostren fortes correlacions temporals i estructurals. A més, les tendències recents en la modelització basada en agents donen suport a un canvi generalitzat de les descripcions basades en els enllaços cap a enfocaments on els nodes són centrals. Aquí desenvolupo un mecanisme d’infecció dotat de memòria a exposicions passades i que simultàniament incorpora l’efecte conjunt de múltiples fonts infeccioses. Una noció de reforç/inhibició social sorgeix de manera orgànica, sense incorporar-se explícitament al model. Com a resultat, els conceptes de dinàmica no markoviana i contagi complex s’acoblen intrínsecament. Derivo aproximacions de camp mitjà per a xarxes aleatòries de grau fix i realitzo extenses simulacions estocàstiques per a xarxes no homogènies. L'anàlisi del model SIS revela una interacció sofisticada entre dos modes de memòria, que es manifesta mitjançant una pèrdua de memòria col·lectiva i la dislocació del punt crític en dues transicions de fase. Apareix una regió intermitja on el sistema és excitable o bistable, amb comportaments fonamentalment diferents en comparació amb les fases sanes i endèmiques habituals. A més, la transició a la fase endèmica esdevé híbrida, mostrant propietats contínues i també discontínues. Aquests resultats proporcionen una visió renovada sobre la interacció entre mecanismes microscòpics i aspectes topològics de les xarxes de contacte subjacents, i el seu efecte conjunt sobre les propietats dels processos de propagació. En particular, aquest tipus de modelització que combina efectes de memòria i contagi complex podria ser adequat per descriure interaccions ecològiques entre patògens biològics i socials.[spa] El modelado epidémico ha demostrado ser un marco esencial para el estudio de los fenómenos de contagio en sistemas biológicos, sociales y técnicos. Aunque los modelos epidémicos han evolucionado hacia potentes herramientas de predicción, la mayoría asumen agentes sin memoria y canales de transmisión independientes. Sin embargo, muchos ejemplos de la vida real muestran fuertes correlaciones temporales y estructurales. Además, las tendencias recientes en la modelización basada en agentes apoyan un cambio generalizado de las descripciones basadas en los enlaces hacia enfoques donde los nodos son centrales. Aquí desarrollo un mecanismo de infección dotado de memoria a exposiciones pasadas y que simultáneamente incorpora el efecto conjunto de múltiples fuentes infecciosas. Una noción de refuerzo/inhibición social surge de manera orgánica, sin incorporarse explícitamente al modelo. Como resultado, los conceptos de dinámica no Markoviana y contagio complejo se acoplan intrínsecamente. Derivo aproximaciones de campo medio para redes aleatorias de grado fijo y realizo extensas simulaciones estocásticas para redes no homogéneas. El análisis del modelo SIS revela una interacción sofisticada entre dos modos de memoria, que se manifiesta mediante una pérdida de memoria colectiva y la dislocación del punto crítico en dos transiciones de fase. Aparece una región intermedia donde el sistema es excitable o bistable, con comportamientos fundamentalmente diferentes en comparación con las fases sanas y endémicas habituales. Además, la transición a la fase endémica se convierte en híbrida, mostrando propiedades continuas y también discontinuas. Estos resultados proporcionan una visión renovada sobre la interacción entre mecanismos microscópicos y aspectos topológicos de las redes de contacto subyacentes, y su efecto conjunto sobre las propiedades de los procesos de propagación. En particular, este tipo de modelización que combina efectos de memoria y contagio complejo podría ser adecuado para describir interacciones ecológicas entre patógenos biológicos y sociales

A Memento of Complexity: The Rhetorics of Memory, Ambience, and Emergence

Drawing from complexity theory, this dissertation develops a schema of rhetorical memory that exhibits extended characteristics. Scholars traditionally conceptualize memory, the fourth canon in classical rhetoric, as place (loci) or image (phantasm). However, memory rhetoric resists the traditional loci-phantasm framework and instead emerges from enmeshments of interiority, collectivity, and technology. Emergence considers the dynamics of fundamental parts that generate complex systems and offers a methodological lens to theorizing memory. The resulting construct informs everyday life, which includes interfacing with pervasive computing or sensing familiarity. Further, congruently with a neurological turn that contradicts simplification, this dissertation resituates rhetorical memory as generative to imagination or perception

Staging Governance

Between 1770 and 1800, transformations in the relationship between metropolitan British society and its colonial holdings, and in the concept of the nation itself, left Britons with a new sense of themselves. Over the same period, the consolidation of the middle classes was accompanied by growing social constraints on sexuality and family life. Staging Governance locates the intersection of these two trends in the representation of British India on the London stage. Theatrical productions, especially those representing colonial life, pushed the limits of public discourse on sexuality and colonialism even as the government made efforts to shape and narrow them. At the same time, official discourse on colonial practices, such as the public trials of Clive and Hastings, became theatrical events themselves. Exploring this rapidly shifting world through a series of original readings of dramatic texts and important moments of oratory, Staging Governance demonstrates how the perceived crises of imperial and domestic Britain joined these spheres in the popular imagination. The economics of political and sexual exchange not only became entwined but functioned as mutual supports during a period of social, cultural, and political readjustment

Involute Analysis: Virtual Discourse, Memory Systems and Archive in the Involutes of Thomas De Quincey

Thomas De Quincey’s involutes inform metaphysical thought on memory and language, particularly concerning multiplicity and the virtual, repetition and difference. When co-opting the mathematic and mechanic involute in Suspiria de Profundis, De Quincey generates an interdisciplinary matrix for the semiotics underpinning his philosophy of language and theory of memory and experience. Involutes entangle and reproduce. De Quincey’s involute exposes the concrete and actual through which all experience accesses the abstract or virtual. The materiality of their informatics and technics provides a literary model and theoretical precursor to a combination of archive and systems theory. The textuality of involute system(s)—both De Quincey\u27s mind and narrative—accommodates the intersections: archive recognizes proliferating layers of re-inscription or a system of discursivity and systems observes the self-regulation of processes and signals/messages in communication. De Quincey\u27s involutes, as a method, transform memory and experience into involute texts: texts invested in the form and layered reading processes of fragmenting and sedimenting data within the strata of memory storage, actively sorted, re-fragmented, reiterated

Crisis and Individuation: Mapping and Navigating the Planetary Crisis Convergence

We live in an era of converging global crises, from climate change and mass extinction to political-economic turbulence, energy depletion, food crises, and emerging technological risks. But how will these crises combine and feedback on each other? How might they unfold over the coming years and decades? And what can be done to solve or at least navigate these crises? This dissertation argues that answers to these questions have been hindered by limited efforts so far, both in the field of International Relations and beyond, to develop more holistic analyses of these crises. In large part this is due to the dominance of “isolationist” approaches to the study of global crisis and the social sciences more generally: the tendency to analytically isolate specific systems and problems from other systems with which they’re connected. While isolationist analyses are vital, I argue that they must be supplemented with multidimensional and synthetic analyses in order to adequately grasp the complexity of the contemporary planetary crisis, or what I call the “planetary crisis convergence”, and understand how it may unfold in the coming decades. Overall, this dissertation presents two core arguments. First, that the contemporary world system is on the cusp of a catastrophic discontinuity that will irreversibly transform livelihoods, states, and world order over the next two to four decades. Second, that to see this imminent rupture, understand its causal drivers, and map its possible future trajectories requires a multi-dimensional systems theoretical approach that encompasses political-economic, technological, geological, and ecological processes. To pursue this analysis I develop a theoretical framework drawing from complexity theory, Marxist political economy, and the philosophy of Gilles Deleuze alongside natural scientific studies on climate change, food and energy systems, and technological change. In this way the dissertation synthesizes quantitative analyses of key trends in climate, food, and energy systems with qualitative analysis of political economy, technology, power, and resistance in order to illuminate the possible trajectories of the planetary crisis convergence and inform counter-hegemonic responses. It concludes that these crises will most likely force a transition in the world-system towards one of three global-scale scenarios: a Techno-Authoritarian Planetary Leviathan, an Ecosocialist world-system, or a global collapse. It proposes that a democratic ecosocialist world-system is needed to respond to the planetary crisis convergence in a genuinely sustainable and just manner, which would involve a new political-economy based on well-being, post-growth principles, and democratic planning at multiple scales

The role of phonology in visual word recognition: evidence from Chinese

Posters - Letter/Word Processing V: abstract no. 5024The hypothesis of bidirectional coupling of orthography and phonology predicts that phonology plays a role in visual word recognition, as observed in the effects of feedforward and feedback spelling to sound consistency on lexical decision. However, because orthography and phonology are closely related in alphabetic languages (homophones in alphabetic languages are usually orthographically similar), it is difficult to exclude an influence of orthography on phonological effects in visual word recognition. Chinese languages contain many written homophones that are orthographically dissimilar, allowing a test of the claim that phonological effects can be independent of orthographic similarity. We report a study of visual word recognition in Chinese based on a mega-analysis of lexical decision performance with 500 characters. The results from multiple regression analyses, after controlling for orthographic frequency, stroke number, and radical frequency, showed main effects of feedforward and feedback consistency, as well as interactions between these variables and phonological frequency and number of homophones. Implications of these results for resonance models of visual word recognition are discussed.postprin