Tube algebras, excitations statistics and compactification in gauge models of topological phases

We consider lattice Hamiltonian realizations of ($d$+1)-dimensional Dijkgraaf-Witten theory. In (2+1)d, it is well-known that the Hamiltonian yields point-like excitations classified by irreducible representations of the twisted quantum double. This can be confirmed using a tube algebra approach. In this paper, we propose a generalization of this strategy that is valid in any dimensions. We then apply the tube algebra approach to derive the algebraic structure of loop-like excitations in (3+1)d, namely the twisted quantum triple. The irreducible representations of the twisted quantum triple algebra correspond to the simple loop-like excitations of the model. Similarly to its (2+1)d counterpart, the twisted quantum triple comes equipped with a compatible comultiplication map and an $R$-matrix that encode the fusion and the braiding statistics of the loop-like excitations, respectively. Moreover, we explain using the language of loop-groupoids how a model defined on a manifold that is $n$-times compactified can be expressed in terms of another model in $n$-lower dimensions. This can in turn be used to recast higher-dimensional tube algebras in terms of lower dimensional analogues.Comment: 71 page

Not so indifferent after all? Self-conscious atheism and the secularisation thesis

Commenting on the lack of self-conscious atheists in apparently secularised Western European societies, the British sociologist Steve Bruce has argued that strong expressions of unbelief are in fact symptomatic of religious cultures. In 1996’s Religion in the Modern World, for instance, he writes: ‘it should be no surprise that, though there are more avowed atheists than there were twenty years ago, they remain rare. Self-conscious atheism and agnosticism are features of religious cultures and [in Britain] were at their height in the Victorian era. They are postures adopted in a world where people are keenly interested in religion.’ (Bruce 1996: 58.) Likewise, discussing possible ‘endpoints’ of European secularisation in 2002’s God is Dead, Bruce states: In so far as I can imagine an endpoint, it would not be conscious irreligion; you have to care too much about religion to be irreligious. It would be widespread indifference (what Weber called being religiously unmusical); no socially significant shared religion; and religious ideas being no more common than would be the case if all minds were wiped blank and people began from scratch to think about the world and their place in it. (Bruce 2002: 42, my emphasis.)Paradoxical though it may sound at first, Bruce’s basic­ argument makes considerable sense. The idea that certain forms of particularly positive atheism – by which I mean a definite belief in the non-existence of a God or gods, as opposed to the simple absence of a belief in the same (negative atheism) – might be motivated, conditioned, or reinforced, by contrast with certain, socially prevalent religious beliefs or practices is scarcely controversial. After all, it would be strange to take one’s atheism seriously in a society where no one took theism seriously. A society that is indifferent to manifestations of religion (such as Bruce and others depict many late-modern western societies as being) ought, therefore, to be just as indifferent to manifestations of ‘nonreligion’

From masterplanning to adaptive planning : understanding the contemporary tools and processes for civic urban order

My research is an examination of the scope of contemporary urban design and planning tools and processes which can act as alternative qualitative methodologies for the renewal of urban conditions at multiple scales through adaptive methods embracing change, stresses and shocks affecting societies and the city as a growing epicentre of human inhabitation and complex systems. With growing urbanisation, the question of what constitutes liveable urbanism across urban territories is a critical one. Addressing the lack of unified and culturally aware analysis of the evolution in urban design and planning practice being applied in various contexts across the developed and developing world, I have, through my own international research programme over more than 15 years, traced their potentials for incubating renewal through a collection of published outputs, each with their own approach: a book, essays for the media and for exhibition catalogues and a webzine. Through examination I have learned about the capacities of tools and processes to break with silo thinking and damaging legacies of the past, and to adapt, or to forge new instrumentalities in ways that are context-responsive and situational. My focus has been on studying largely ongoing, phased projects, so this is a work in progress. This self-appointed intellectual mandate for comparative urbanism has required a form of evaluation that includes consideration of the use and mis-use of history and old rules, operational narratives and contestory factors, enquiry into assumptions made, responsibilities claimed, and objectives combining issues of determination (of plans, by their clients) and self-determination (of communities). I have striven to show how the recognition of planning baggage and the emptying out of its tactics, is, in diverse ways, creating space for alternative behaviors in the form of new, potentially more socially equitable and responsive patterns of operation, engaging and reusing resources. I have learned that new hybrid processes of top down and bottom up planning, and interest in engaging with multi-modal approaches with their relative novelty and unprecedented forms of complexity, represent major challenges to long-held beliefs about planning’s role in society and the typical relationships between planner and those planned for. They foster a sense of the symbiotic relationships, interdependencies, alliances and self-determination cities need to generate their futures in socially equitable and resilient ways. My body of research will help inform and contribute methodologies and concepts to future outputs on related themes concerning urban design and planning’s role and identity, including issues of Urbanista.org, my webzine. The wider implications of my research are also that institutions involved in land use of all kinds accordingly need to carry a responsibility to adopt a higher commitment to the value of and need for adaptive instruments of civic urban order

Economic models of church life: Three nudges towards better behaviour

Economic ideas have long shed light on diverse spheres of social and cultural life. Religion is no exception and has spawned a large and thriving subfield. However, whereas recent decades have famously witnessed a ‘behavioural’ turn in economics – with Nobel prizes going to two pioneers of the field, Daniel Kahneman in 2002 and Richard Thaler in 2017 – there has yet to be significant work done in the ‘behavioural economics of religion’. This is a shame; there are good reasons for thinking that behavioural-economic theories and findings might be particularly well suited to illumine several areas of practical church life. In what is hopefully a light and quasi-entertaining way, this article offers (wildly speculative!) applications of behavioural economic ideas to three live topics within the sociology of religion and/or pastoral theology: the ‘empty’ church, the success of US megachurches, and church planting

The contribution of knowing practice to the theory–practice ‘divide’ in global learning

This article draws on research exploring how practitioners in development education centres (DECs) in England conceptualise global learning and understand the relationship between theory and practice. It responds to ongoing critique that when it comes to practice, there is a lack of clarity and reflection on conceptual and theoretical issues, and their implications for what practitioners know and do. Informed by critical grounded theory, the research analysed data obtained through focus groups which were designed to engage practitioners in a process of reflecting on their work collaboratively and critically. While findings from an early analysis of responses appeared to support arguments about a weak theory–practice relationship, revisiting participants’ emphasis on what they do as practice prompted exploration of the literature on similar debates in wider professional contexts. This introduced insights centred on concepts of embodied and ‘knowing practice’. Applying these concepts back to the data supported evidence of a more complex and symbiotic relationship between theory and practice in some participants’ responses. This was significant in reframing the theory–practice divide assumed by the research aims, shifting the emphasis from knowledge to practice, and opening up questions about what knowledge and practice means in the context of DECs. It also empowered practitioners by alerting them to possibilities for engaging more actively with knowledge and transforming their practice collectively

RHEOLOGICAL CHARACTERIZATION OF SUSPENSIONS

The aim of this research is to obtain a meaningful rheological characterization of deflocculated china clay suspensions. It is generally true that in the study of suspensions relatively little successful work has been carried out on the flow properties of highly concentrated suspensions as compared with dilute suspensions; it was decided therefore that the work, presented in this thesis, should be confined to the study of higher concentration suspensions. A survey is given of previous work on the rheological characterization of suspensions and the reasons for choosing the clay suspensions in particular, are discussed. Since a knowledge of the microscopic nature of the particles in suspension is important for the understanding of the macroscopic behaviour of the suspensions, a detailed account of the relevant aspects of clay and its rheological behaviour is presented. The investigation consists of a theoretical and experimental study of the suspensions. The experimental results are obtained by using a commercial rheometer, the Weissenberg Rheogoniometer. Experiments are performed which include steady shear studies, oscillatory shear studies and studies of a combined steady and low-amplitude oscillatory shear flow. A theory is developed for this latter flow situation and expressions for the percentage increase in couple are obtained based on different rheological equations of state. Concentration effects are examined and it is shown that, with increasing concentration, an initial shear thinning region is followed by a shear thickening one. It is also found that marked elastic properties are exhibited by these highly concentrated clay suspensions. Qualitative agreement is obtained between theory and experiment for all suspensions considered and at the highest concentrations it is shown (for the first time) that it is possible to characterize shear thinning and shear thickening properties of a fluid using one equation of state. The experimental results indicate that this programme of work may have important implications for certain industrial nearly viscometric flow situations as well as the whole approach being applicable to other concentrated suspension systems

Encouraging student to reflect on their employment experience

The purpose behind this case study is to share with a wider audience of placement officers, tutors and those who are involved in the management of placement students or employment of graduates, the approach taken to encourage reflective learning in undergraduate placement students at Aston Business School. Reflective learning forms an important foundation of the placement year at Aston Business School, where a professional placement is a mandatory element of the four year degree, for all Home/EU students (optional for International students) who are taking a Single Honours degree (i.e. a fully business programme). The placement year is not compulsory for those students taking a Combined Honours degree (i.e. a degree where two unrelated subjects are studied), although approximately 50% of those students taking an Aston Business School subject opt to take a placement year. Students spend their year out undertaking a ‘proper’ job within a company or public sector organisation. They are normally paid a reasonable salary for their work (in 2004/5 the average advertised salary was £13,700 per annum). The placement year is assessed, carrying credits which amount to a contribution of 10% towards the students’ final degree. The assessment methods used require the students to submit an academic essay relating theory to practice, a factual report about the company which can be of use to future students, and a log book, the latter being the reflective piece of work. Encouragement to reflect on the placement year has always been an important feature of Aston Business School’s approach to learning. More recently, however, feedback from employers indicated that, although our students have excellent employability skills, “they do not think about them” (Aston Business School Advisory Panel, 2001). We, therefore, began some activities which would encourage students to go beyond the mere acquisition of skills and knowledge. This work became the basis of a programme of introductions to reflective learning, mentoring and awareness of different learning styles written up in Higson and Jones (2002). The idea was to get students used to the idea of reflection on their experiences well before they entered the placement year

Access Riders (web)

Jemina Lindholm, Jessie Bullivant, Camille Auer, Nora Heidorn, Heidi & Kaino Wennerstrand (BIITSI), Jenni-Juulia Wallinheimo-Heimonen, Anonymous An access rider is written by an individual, and can be shared when one is invited to take part in a project or any working relationship. It can work as a starting point for a conversation between the inviter and invitee about the accessibility of a certain situation. Access Riders is a collaborative project by artists Jessie Bullivant and Jemina Lindholm. The project is a compilation of access riders by eight of the contributors to Frame Contemporary Art Finland\u27s Rehearsing Hospitalities event. The access riders in this compilation vary in style, length and language, and reflect the range of needs, wants, limits and boundaries. Access Riders is printed as a limited edition of 100 copies and is available online at https://frame-finland.fi/en/resources/ in two PDF formats: one is designed for printing at home and the other for reading on a screen (including the use of screen readers)https://pdxscholar.library.pdx.edu/access_riders/1000/thumbnail.jp