Modular Invariants and Twisted Equivariant K-theory II: Dynkin diagram symmetries

The most basic structure of chiral conformal field theory (CFT) is the Verlinde ring. Freed-Hopkins-Teleman have expressed the Verlinde ring for the CFT's associated to loop groups, as twisted equivariant K-theory. We build on their work to express K-theoretically the structures of full CFT. In particular, the modular invariant partition functions (which essentially parametrise the possible full CFTs) have a rich interpretation within von Neumann algebras (subfactors), which has led to the developments of structures of full CFT such as the full system (fusion ring of defect lines), nimrep (cylindrical partition function), alpha-induction etc. Modular categorical interpretations for these have followed. For the generic families of modular invariants (i.e. those associated to Dynkin diagram symmetries), we provide a K-theoretic framework for these other CFT structures, and show how they relate to D-brane charges and charge-groups. We also study conformal embeddings and the E7 modular invariant of SU(2), as well as some families of finite group doubles. This new K-theoretic framework allows us to simplify and extend the less transparent, more ad hoc descriptions of these structures obtained previously within CFT.Comment: 49 pages; more explanatory material added; minor correction

Low temperatures studies of channel compounds

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Tracking based product authentication: Catching intruders in the supply chain

This paper describes how IS offshoring organisations are changing in response to increased globalisation of the practice of software development. It posits the emergence of a new form of multinational enterprise (MNE), described in this paper as a ‘modern heterarchy’, from the construct of the heterarchy originally developed by Gunnar Hedlund in 1986. The paper draws on theoretical antecedents in the discipline of international business studies, and is supported by empirical data gathered from two extended case studies of offshore IS projects. The research uses grounded theory techniques for the collection and analysis of data, and has particular value for IS practitioners in offshore IS MNEs

Assessing the impacts of IS offshoring: preliminary conclusions questioning the validity of cultural consideration

This paper defines an analytic framework with which to research the impact of IS offshoring on its various stakeholders and applies this to two significant case studies of offshoring in the financial services industry. It presents conclusions on one particular segment of the research programme, namely the extent to which IS offshoring drives cultural change for IS practitioners in offshore locations. It concludes that the resultant impact is notable, but not different in any significant way to that experienced by any IS practitioner who works overseas. Further, the cultural differences between onshore and offshore practitioners tend to diminish quickly as they adapt to new cultural environments

IS offshoring: a proposed maturity model of offshore IS suppliers

Companies in developed economies are now accustomed to use offshore IS services to develop and maintain software, and an increasing number of specialist offshore services firms exists to meet the demand. These include systems integrators whose origins are in developed economies, and ‘pure play’ offshore IS providers that originate in countries where the cost of IS labour is relatively low. Both type of offshore organisation have changed considerably in recent years in response to market demand and competitive pressure. Although researchers have developed maturity models for users of IS offshoring, there is little that describes the nature and behaviour of offshore IS providers. Accordingly, this paper proposes a maturity model for offshore IS suppliers that is analogous to various consumer-oriented maturity models found in the literature and in trade journals. This preliminary framework is developed by reference to literature on outsourcing, offshoring and IS maturity models, and by recent relevant experience of practitioner organisations. The conclusions from this study can be used to guide further research, and to develop constructs helpful to practitioners. The research helps suppliers of offshore IS services to understand the particular conditions in which it is appropriate to consider new business models. For consumers of offshore outsourcing, it provides a framework for categorising suppliers of IS services