Heterotic-string amplitudes at one loop: modular graph forms and relations to open strings

We investigate one-loop four-point scattering of non-abelian gauge bosons in heterotic string theory and identify new connections with the corresponding open-string amplitude. In the low-energy expansion of the heterotic-string amplitude, the integrals over torus punctures are systematically evaluated in terms of modular graph forms, certain non-holomorphic modular forms. For a specific torus integral, the modular graph forms in the low-energy expansion are related to the elliptic multiple zeta values from the analogous open-string integrations over cylinder boundaries. The detailed correspondence between these modular graph forms and elliptic multiple zeta values supports a recent proposal for an elliptic generalization of the single-valued map at genus zero.Comment: 57+22 pages, v2: references updated, version published in JHE

CORRELATING HEALTH EXAMINATIONS WITH CLASS TEACHING

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72995/1/j.1746-1561.1934.tb09593.x.pd

HEALTH EXAMINATIONS IN SCHOOLS

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72912/1/j.1746-1561.1933.tb09250.x.pd

Rigid Calabi-Yau threefolds, Picard Eisenstein series and instantons

Type IIA string theory compactified on a rigid Calabi-Yau threefold gives rise to a classical moduli space that carries an isometric action of U(2,1). Various quantum corrections break this continuous isometry to a discrete subgroup. Focussing on the case where the intermediate Jacobian of the Calabi-Yau admits complex multiplication by the ring of quadratic imaginary integers O_d, we argue that the remaining quantum duality group is an arithmetic Picard modular group PU(2,1;O_d). Based on this proposal we construct an Eisenstein series invariant under this duality group and study its non-Abelian Fourier expansion. This allows the prediction of non-perturbative effects, notably the contribution of D2- and NS5-brane instantons. The present work extends our previous analysis in 0909.4299 which was restricted to the special case of the Gaussian integers O_1=Z[i].Comment: 8 pages, for the proceedings of Quantum Theories and Symmetries V

Dynamic Capabilities: Innovation Project Portfolio Management

Innovation Project Portfolio Management (IPPM) practices are a dynamic capability that provides competitive advantage by dynamically adjusting the organisation’s portfolio of projects and resource allocation profile for the best innovation outcomes. A relatively new body of empirical research into IPPM practices is starting to generate findings related to IPPM practices and innovation outcomes. However this research is fragmented and lacks a unifying theoretical base. The resource-based view of strategy, in particular the dynamic capabilities approach, provides a theoretical framework to unify IPPM research. A ‘processes, positions and paths’ perspective on IPPM practices helps to clarify the ways that IPPM practices contribute to competitive advantage. Existing empirical research into the processes used for IPPM reveals some links to innovation outcomes, but does not try to explain causality. Improved understanding of the mechanisms responsible for competitive advantage through IPPM practices is found in research on positions (how IPPM processes draw upon and contribute to the underlying resource position) and paths (the role of past decisions and organisational paths in shaping IPPM processes as well as future options and decisions).14 page(s

Project portfolio management for product innovation

The purpose of this paper is to create a benchmark and identify best practices for Project Portfolio Management (PPM) for both tangible product-based and service product-based development project portfolios. A questionnaire was developed to gather data to compare the PPM methods used, PPM performance, PPM challenges, and resulting new product success measures in 60 Australian organisations in a diverse range of service and manufacturing industries. The paper finds that PPM practices are shown to be very similar for service product development project portfolios and tangible product development project portfolios. New product success rates show strong correlation with measures of PPM performance and the use of some PPM methods is correlated with specific PPM performance outcomes. The findings in this paper are based on a survey of a diverse sample of 60 Australian organisations. The results are strengthened by comparisons with similar North American research; however, they may not be representative of all environments. Research in other regions would further qualify the findings. As each organisation's PPM process is unique, case study methods are recommended for future studies to capture more of the complexity in the environment. The paper shows that PPM practitioners and executives who make decisions about the development of tangible products and/or service products will benefit from the findings. This paper extends the existing understanding of PPM practices to include service development project portfolios as well as tangible product development project portfolios and strengthens the links between PPM practices and outcomes

Learning investments and organizational capabilities: case studies on the development of project portfolio management capabilities

Purpose The purpose of this paper is to improve understanding and provide guidance for investments in organizational learning mechanisms for the establishment and evolution of organizational capabilities such as project portfolio management (PPM) and project management capabilities. Design/methodology/approach A multiple-case study research project investigates the development of PPM capabilities in six successful organizations across diverse industries. Findings The research indicates that PPM and organizational learning are dynamic capabilities that enhance an organization's ability to achieve and maintain competitive advantage in dynamic environments. PPM capabilities are shown to co-evolve through a combination of tacit experience accumulation, explicit knowledge articulation and explicit knowledge codification learning mechanisms. Although all three learning mechanisms are important throughout the establishment and evolution of PPM capability development, the research indicates that the development of an effective PPM capability will require particularly strong investments in enhancing tacit experience accumulation mechanisms and explicit knowledge codification mechanisms during the initial establishment or during periods of radical change to the PPM process

An E9 multiplet of BPS states

We construct an infinite E9 multiplet of BPS states for 11D supergravity. For each positive real root of E9 we obtain a BPS solution of 11D supergravity, or of its exotic counterparts, depending on two non-compact transverse space variables. All these solutions are related by U-dualities realised via E9 Weyl transformations in the regular embedding of E9 in E10, E10 in E11. In this way we recover the basic BPS solutions, namely the KK-wave, the M2 brane, the M5 brane and the KK6-monopole, as well as other solutions admitting eight longitudinal space dimensions. A novel technique of combining Weyl reflexions with compensating transformations allows the construction of many new BPS solutions, each of which can be mapped to a solution of a dual effective action of gravity coupled to a certain higher rank tensor field. For real roots of E10 which are not roots of E9, we obtain additional BPS solutions transcending 11D supergravity (as exemplified by the lowest level solution corresponding to the M9 brane). The relation between the dual formulation and the one in terms of the original 11D supergravity fields has significance beyond the realm of BPS solutions. We establish the link with the Geroch group of general relativity, and explain how the E9 duality transformations generalize the standard Hodge dualities to an infinite set of `non-closing dualities'.Comment: 76 pages, 6 figure