Cubical methods in homotopy type theory and univalent foundations

Cubical methods have played an important role in the development of Homotopy Type Theory and Univalent Foundations (HoTT/UF) in recent years. The original motivation behind these developments was to give constructive meaning to Voevodsky’s univalence axiom, but they have since then led to a range of new results. Among the achievements of these methods is the design of new type theories and proof assistants with native support for notions from HoTT/UF, syntactic and semantic consistency results for HoTT/UF, as well as a variety of independence results and establishing that the univalence axiom does not increase the proof theoretic strength of type theory. This paper is based on lecture notes that were written for the 2019 Homotopy Type Theory Summer School at Carnegie Mellon University. The goal of these lectures was to give an introduction to cubical methods and provide sufficient background in order to make the current research in this very active area of HoTT/UF more accessible to newcomers. The focus of these notes is hence on both the syntactic and semantic aspects of these methods, in particular on cubical type theory and the various cubical set categories that give meaning to these theories.

The Singleton Fallacy: Why Current Critiques of Language Models Miss the Point

This paper discusses the current critique against neural network-based Natural Language Understanding solutions known as language models. We argue that much of the current debate revolves around an argumentation error that we refer to as the singleton fallacy: the assumption that a concept (in this case, language, meaning, and understanding) refers to a single and uniform phenomenon, which in the current debate is assumed to be unobtainable by (current) language models. By contrast, we argue that positing some form of (mental) “unobtanium” as definiens for understanding inevitably leads to a dualistic position, and that such a position is precisely the original motivation for developing distributional methods in computational linguistics. As such, we argue that language models present a theoretically (and practically) sound approach that is our current best bet for computers to achieve language understanding. This understanding must however be understood as a computational means to an end.

Wspólnota przez świętowanie. Nauryz we współczesnym Kazachstanie

The author aims to capture the significance of the celebration of Nauryz, the ancient celebration of spring, family, and local community. She describes various forms of celebrating Nauryz on the official, national, local, and family level in Kazakhstan. She emphasizes that the renewed tradition of celebrating Nauryz is part of a process deliberately adopted by the Kazakh authorities in the post-Soviet period in order to build a community from a state of many ethnicities. She states that all the ways of celebrating Nauryz appeal to the original motivation of sustaining, restoring, and strengthening the community. This leads to the formation of communitas (in Victor Turner’s sense), which is conducive to forming the inhabitants of modern Kazakhstan into a multi-ethnic community.

Sensitivities of the Madden–Julian oscillation forecasts to configurations of physics in the ECMWF global model

The sensitivities of the Madden–Julian oscillation (MJO) forecasts to various different configurations of the parameterized physics are examined with the global model of ECMWF's Integrated Forecasting System (IFS). The motivation for the study was to simulate the MJO as a nonlinear free wave under active interactions with higher-latitude Rossby waves. To emulate free dynamics in the IFS, various momentum-dissipation terms (“friction”) as well as diabatic heating were selectively turned off over the tropics for the range of the latitudes from 20∘ S to 20∘ N. The reduction of friction sometimes improves the MJO forecasts, although without any systematic tendency. Contrary to the original motivation, emulating free dynamics with an operational forecast model turned out to be rather difficult, because forecast performance sensitively depends on the specific type of friction turned off. The result suggests the need for theoretical investigations that much more closely follow the actual formulations of model physics: a naive approach with a dichotomy of with or without friction simply fails to elucidate the rich behaviour of complex operational models. The paper further exposes the importance of physical processes other than convection for simulating the MJO in global forecast models.

Image-guided raytracing and its applications

Eikonal solvers have found important applications in seismic data processing and in-version, the so-called image-guided methods. To this day in image-guided applications, thesolution of the eikonal equation is implemented using partial-differential-equationsolvers, such as fast-marching or fast-sweeping methods. We show that alternatively, onecan numerically integrate the dynamic Hamiltonian system defined by the image-guidedeikonal equation and reconstruct the solution with image-guided rays. We present interest-ing applications of image-guided raytracing to seismic data processing, demonstrating theuse of the resulting rays in image-guided interpolation and smoothing, well-log interpola-tion, image flattening, and residual-moveout picking. Some of these applications make useof properties of the raytracing system that are not directly obtained by eikonal solvers, suchas ray position, ray density, wavefront curvature, and ray curvature. These ray propertiesopen space for a different set of applications of the image-guided eikonal equation, beyondthe original motivation of accelerating the construction of minimum distance tables. Westress that image-guided raytracing is an embarrassingly parallel problem, which makes itsimplementation highly efficient on massively parallel platforms. Image-guided raytracing isadvantageous for most applications involving the tracking of seismic events and imaging-guided interpolation. Our numerical experiments using synthetic and real data sets showthe efficiency and robustness of image-guided rays for the selected applications.

Autocrats versus terrorists : what Conditions authoritarian counter-terrorism?

This dissertation explores the breadth and variation of authoritarian counter-terrorism strategies and their legitimacy-related origins to challenge prevailing assumptions in Terrorism Studies. Research and analysis are conducted in the form of a Structured Focused Comparison of domestic counter-terrorism strategies in two electoral autocracies. The first case is Russia’s domestic engagement against a mix of ethno-separatist and Islamist terrorism emanating from its North Caucasus republics between 1999 and 2018. The second case is China’s engagement vis-à-vis a similar type of terrorism in its Xinjiang Uyghur Autonomous Region between 1990 and 2018. The comparison shows that, contrary to prevailing assumptions, the two strategies differ immensely from one another while containing significant if not predominant non-coercive elements. It further shows that the two strategies are closely related to the two states’ sources and resources of legitimacy, both in their original motivation to tackle the terrorist threat and in the design of counter-terrorism strategies. Drawing on David Beetham’s theory of The Legitimation of Power and on the Comparative Politics, Terrorism Studies and Civil War literatures, the dissertation explores the influence of five sources and (re)sources of legitimacy on the two counter-terrorism strategies: responsiveness, performance legitimacy, ideology, discursive power and co-optation. While governmental discursive power is discarded as a source of variation, findings are significant with respect to the influence of ideology and performance legitimacy. Reliance on ideology or related patterns for legitimation raise vulnerability to terrorism and constrain or facilitate the adoption of communicative and preventive measures that accommodate the grievances of potentially defective or even violently terrorist groups. Performance legitimacy is a key motivator in counter-terrorism and an influence on certain types of counter-terrorism policies. Responsiveness and co-optation are identified as potential sources of variation, based on idiosyncratic concurrence with policy choices.

Curved Rickard complexes and link homologies

Rickard complexes in the context of categorified quantum groups can be used to construct braid group actions. We define and study certain natural deformations of these complexes which we call curved Rickard complexes. One application is to obtain deformations of link homologies which generalize those of Batson–Seed [3] [J. Batson and C. Seed, A link-splitting spectral sequence in Khovanov homology, Duke Math. J. 164 2015, 5, 801–841] and Gorsky–Hogancamp [E. Gorsky and M. Hogancamp, Hilbert schemes and y-ification of Khovanov–Rozansky homology, preprint 2017] to arbitrary representations/partitions. Another is to relate the deformed homology defined algebro-geometrically in [S. Cautis and J. Kamnitzer, Knot homology via derived categories of coherent sheaves IV, colored links, Quantum Topol. 8 2017, 2, 381–411] to categorified quantum groups (this was the original motivation for this paper).

Dance and the (Digital) Archive: A Survey of the Field

This paper offers a conspectus of several online dance archives made in the context of the Portuguese research project TKB. The online searches we conducted from 2018 to the end of 2019 suggested four broad categories of resources for what one may call ‘online dance archives’. Aiming to observe how dance resources are available on the internet, we made each category correspond to a different operation – to collect (to build up a collection), to accumulate (to gather almost random material), to store (to organize according to a set of rules), to assemble (to compose and curate material). And we posed the same set of questions: for each of these categories: what is the mission of the archive, who are its subjects and objects, and which community of users does it bring together? The outcome is both a general overview, and the possibility of a comparative approach. Our original motivation has been to survey and to analyse a sample of available online resources for dance documentation and/or archiving, in order to feed TKB future projects and experiences. Starting from the TKB project perspective, and aiming at categorizing the different approaches to storage, curation, ownership and availability reflected by those archival platforms, we finally identified three major challenges in the relation between dance and the digital archive: the question of access, the ontology of dance and archive – what it is, what it has been, and what ‘dance and archiving’ can become in the future –, and the ‘Will to archive’ (cf. Lepecki 2010 ). Each one of these challenges will eventually provoke new questions as to the future of the TKB project and of its team of researchers, and the nature of the work they may undertake.

Narrative medicine: Re-engaging and re-energizing ourselves through story

Physicians and other allied health professionals have many distractions from their work and from original motivations to become health caring professionals. Activities that detract from making meaningful connection with patients result in high levels of work dissatisfaction and burnout even at early stages of career or training. Narrative Medicine provides an antidote to these influences. It is an experiential discipline that draws on the Arts and Humanities, connects health professionals to their original motivation to care, cultivates the ability to engage patients and stimulates professional growth. When practiced with interdisciplinary teams, commonalities and mutual purpose are highlighted, promoting group cohesion and appreciation. The practice of this discipline and development of narrative competence relates closely to the advancement along numerous milestones, particularly Patient Care, Interpersonal and Communication Skills, and Professionalism. This article describes an experiential and didactic workshop presented at the 2019 Forum for Behavioral Science in Family Medicine which outlined a Narrative Medicine curriculum as taught at a community hospital Family Medicine residency. The curriculum is aimed at promoting residents’ professional development, personal wellbeing, and capacity to engage patients.